1 /*
   2  * Copyright (c) 1999, 2018, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package com.sun.tools.javac.jvm;
  27 
  28 import java.io.*;
  29 import java.util.LinkedHashMap;
  30 import java.util.Map;
  31 import java.util.Set;
  32 import java.util.HashSet;
  33 import java.util.LinkedHashSet;
  34 import java.util.stream.Collectors;
  35 
  36 import javax.tools.JavaFileManager;
  37 import javax.tools.FileObject;
  38 import javax.tools.JavaFileManager.Location;
  39 import javax.tools.JavaFileObject;
  40 
  41 import com.sun.tools.javac.code.*;
  42 import com.sun.tools.javac.code.Attribute.RetentionPolicy;
  43 import com.sun.tools.javac.code.Directive.*;
  44 import com.sun.tools.javac.code.Symbol.*;
  45 import com.sun.tools.javac.code.Type.*;
  46 import com.sun.tools.javac.code.Types.UniqueType;
  47 import com.sun.tools.javac.comp.Check;
  48 import com.sun.tools.javac.file.PathFileObject;
  49 import com.sun.tools.javac.jvm.Pool.DynamicMethod;
  50 import com.sun.tools.javac.jvm.Pool.Method;
  51 import com.sun.tools.javac.jvm.Pool.MethodHandle;
  52 import com.sun.tools.javac.jvm.Pool.Variable;
  53 import com.sun.tools.javac.util.*;
  54 
  55 import static com.sun.tools.javac.code.Flags.*;
  56 import static com.sun.tools.javac.code.Kinds.Kind.*;
  57 import static com.sun.tools.javac.code.Scope.LookupKind.NON_RECURSIVE;
  58 import static com.sun.tools.javac.code.TypeTag.*;
  59 import static com.sun.tools.javac.main.Option.*;
  60 
  61 import static javax.tools.StandardLocation.CLASS_OUTPUT;
  62 
  63 /** This class provides operations to map an internal symbol table graph
  64  *  rooted in a ClassSymbol into a classfile.
  65  *
  66  *  <p><b>This is NOT part of any supported API.
  67  *  If you write code that depends on this, you do so at your own risk.
  68  *  This code and its internal interfaces are subject to change or
  69  *  deletion without notice.</b>
  70  */
  71 public class ClassWriter extends ClassFile {
  72     protected static final Context.Key<ClassWriter> classWriterKey = new Context.Key<>();
  73 
  74     private final Options options;
  75 
  76     /** Switch: verbose output.
  77      */
  78     private boolean verbose;
  79 
  80     /** Switch: emit source file attribute.
  81      */
  82     private boolean emitSourceFile;
  83 
  84     /** Switch: generate CharacterRangeTable attribute.
  85      */
  86     private boolean genCrt;
  87 
  88     /** Switch: describe the generated stackmap.
  89      */
  90     private boolean debugstackmap;
  91 
  92     /** Preview language level.
  93      */
  94     private Preview preview;
  95 
  96     /**
  97      * Target class version.
  98      */
  99     private Target target;
 100 
 101     /**
 102      * Source language version.
 103      */
 104     private Source source;
 105 
 106     /** Type utilities. */
 107     private Types types;
 108 
 109     private Check check;
 110 
 111     /**
 112      * If true, class files will be written in module-specific subdirectories
 113      * of the CLASS_OUTPUT location.
 114      */
 115     public boolean multiModuleMode;
 116 
 117     /** The initial sizes of the data and constant pool buffers.
 118      *  Sizes are increased when buffers get full.
 119      */
 120     static final int DATA_BUF_SIZE = 0x0fff0;
 121     static final int POOL_BUF_SIZE = 0x1fff0;
 122 
 123     /** An output buffer for member info.
 124      */
 125     ByteBuffer databuf = new ByteBuffer(DATA_BUF_SIZE);
 126 
 127     /** An output buffer for the constant pool.
 128      */
 129     ByteBuffer poolbuf = new ByteBuffer(POOL_BUF_SIZE);
 130 
 131     /** The constant pool.
 132      */
 133     Pool pool;
 134 
 135     /** The inner classes to be written, as a set.
 136      */
 137     Set<ClassSymbol> innerClasses;
 138 
 139     /** The inner classes to be written, as a queue where
 140      *  enclosing classes come first.
 141      */
 142     ListBuffer<ClassSymbol> innerClassesQueue;
 143 
 144     /** The bootstrap methods to be written in the corresponding class attribute
 145      *  (one for each invokedynamic)
 146      */
 147     Map<DynamicMethod.BootstrapMethodsKey, DynamicMethod.BootstrapMethodsValue> bootstrapMethods;
 148 
 149     /** The log to use for verbose output.
 150      */
 151     private final Log log;
 152 
 153     /** The name table. */
 154     private final Names names;
 155 
 156     /** Access to files. */
 157     private final JavaFileManager fileManager;
 158 
 159     /** Sole signature generator */
 160     private final CWSignatureGenerator signatureGen;
 161 
 162     /** The tags and constants used in compressed stackmap. */
 163     static final int SAME_FRAME_SIZE = 64;
 164     static final int SAME_LOCALS_1_STACK_ITEM_EXTENDED = 247;
 165     static final int SAME_FRAME_EXTENDED = 251;
 166     static final int FULL_FRAME = 255;
 167     static final int MAX_LOCAL_LENGTH_DIFF = 4;
 168 
 169     /** Get the ClassWriter instance for this context. */
 170     public static ClassWriter instance(Context context) {
 171         ClassWriter instance = context.get(classWriterKey);
 172         if (instance == null)
 173             instance = new ClassWriter(context);
 174         return instance;
 175     }
 176 
 177     /** Construct a class writer, given an options table.
 178      */
 179     protected ClassWriter(Context context) {
 180         context.put(classWriterKey, this);
 181 
 182         log = Log.instance(context);
 183         names = Names.instance(context);
 184         options = Options.instance(context);
 185         preview = Preview.instance(context);
 186         target = Target.instance(context);
 187         source = Source.instance(context);
 188         types = Types.instance(context);
 189         check = Check.instance(context);
 190         fileManager = context.get(JavaFileManager.class);
 191         signatureGen = new CWSignatureGenerator(types);
 192 
 193         verbose        = options.isSet(VERBOSE);
 194         genCrt         = options.isSet(XJCOV);
 195         debugstackmap = options.isSet("debug.stackmap");
 196 
 197         emitSourceFile = options.isUnset(G_CUSTOM) ||
 198                             options.isSet(G_CUSTOM, "source");
 199 
 200         String modifierFlags = options.get("debug.dumpmodifiers");
 201         if (modifierFlags != null) {
 202             dumpClassModifiers = modifierFlags.indexOf('c') != -1;
 203             dumpFieldModifiers = modifierFlags.indexOf('f') != -1;
 204             dumpInnerClassModifiers = modifierFlags.indexOf('i') != -1;
 205             dumpMethodModifiers = modifierFlags.indexOf('m') != -1;
 206         }
 207     }
 208 
 209 /******************************************************************
 210  * Diagnostics: dump generated class names and modifiers
 211  ******************************************************************/
 212 
 213     /** Value of option 'dumpmodifiers' is a string
 214      *  indicating which modifiers should be dumped for debugging:
 215      *    'c' -- classes
 216      *    'f' -- fields
 217      *    'i' -- innerclass attributes
 218      *    'm' -- methods
 219      *  For example, to dump everything:
 220      *    javac -XDdumpmodifiers=cifm MyProg.java
 221      */
 222     private boolean dumpClassModifiers; // -XDdumpmodifiers=c
 223     private boolean dumpFieldModifiers; // -XDdumpmodifiers=f
 224     private boolean dumpInnerClassModifiers; // -XDdumpmodifiers=i
 225     private boolean dumpMethodModifiers; // -XDdumpmodifiers=m
 226 
 227 
 228     /** Return flags as a string, separated by " ".
 229      */
 230     public static String flagNames(long flags) {
 231         StringBuilder sbuf = new StringBuilder();
 232         int i = 0;
 233         long f = flags & StandardFlags;
 234         while (f != 0) {
 235             if ((f & 1) != 0) {
 236                 sbuf.append(" ");
 237                 sbuf.append(flagName[i]);
 238             }
 239             f = f >> 1;
 240             i++;
 241         }
 242         return sbuf.toString();
 243     }
 244     //where
 245         private final static String[] flagName = {
 246             "PUBLIC", "PRIVATE", "PROTECTED", "STATIC", "FINAL",
 247             "SUPER", "VOLATILE", "TRANSIENT", "NATIVE", "INTERFACE",
 248             "ABSTRACT", "STRICTFP"};
 249 
 250 /******************************************************************
 251  * Output routines
 252  ******************************************************************/
 253 
 254     /** Write a character into given byte buffer;
 255      *  byte buffer will not be grown.
 256      */
 257     void putChar(ByteBuffer buf, int op, int x) {
 258         buf.elems[op  ] = (byte)((x >>  8) & 0xFF);
 259         buf.elems[op+1] = (byte)((x      ) & 0xFF);
 260     }
 261 
 262     /** Write an integer into given byte buffer;
 263      *  byte buffer will not be grown.
 264      */
 265     void putInt(ByteBuffer buf, int adr, int x) {
 266         buf.elems[adr  ] = (byte)((x >> 24) & 0xFF);
 267         buf.elems[adr+1] = (byte)((x >> 16) & 0xFF);
 268         buf.elems[adr+2] = (byte)((x >>  8) & 0xFF);
 269         buf.elems[adr+3] = (byte)((x      ) & 0xFF);
 270     }
 271 
 272     /**
 273      * Signature Generation
 274      */
 275     private class CWSignatureGenerator extends Types.SignatureGenerator {
 276 
 277         /**
 278          * An output buffer for type signatures.
 279          */
 280         ByteBuffer sigbuf = new ByteBuffer();
 281 
 282         CWSignatureGenerator(Types types) {
 283             super(types);
 284         }
 285 
 286         /**
 287          * Assemble signature of given type in string buffer.
 288          * Check for uninitialized types before calling the general case.
 289          */
 290         @Override
 291         public void assembleSig(Type type) {
 292             switch (type.getTag()) {
 293                 case UNINITIALIZED_THIS:
 294                 case UNINITIALIZED_OBJECT:
 295                     // we don't yet have a spec for uninitialized types in the
 296                     // local variable table
 297                     assembleSig(types.erasure(((UninitializedType)type).qtype));
 298                     break;
 299                 default:
 300                     super.assembleSig(type);
 301             }
 302         }
 303 
 304         @Override
 305         protected void append(char ch) {
 306             sigbuf.appendByte(ch);
 307         }
 308 
 309         @Override
 310         protected void append(byte[] ba) {
 311             sigbuf.appendBytes(ba);
 312         }
 313 
 314         @Override
 315         protected void append(Name name) {
 316             sigbuf.appendName(name);
 317         }
 318 
 319         @Override
 320         protected void classReference(ClassSymbol c) {
 321             enterInner(c);
 322         }
 323 
 324         private void reset() {
 325             sigbuf.reset();
 326         }
 327 
 328         private Name toName() {
 329             return sigbuf.toName(names);
 330         }
 331 
 332         private boolean isEmpty() {
 333             return sigbuf.length == 0;
 334         }
 335     }
 336 
 337     /**
 338      * Return signature of given type
 339      */
 340     Name typeSig(Type type) {
 341         Assert.check(signatureGen.isEmpty());
 342         //- System.out.println(" ? " + type);
 343         signatureGen.assembleSig(type);
 344         Name n = signatureGen.toName();
 345         signatureGen.reset();
 346         //- System.out.println("   " + n);
 347         return n;
 348     }
 349 
 350     /** Given a type t, return the extended class name of its erasure in
 351      *  external representation.
 352      */
 353     public Name xClassName(Type t) {
 354         if (t.hasTag(CLASS)) {
 355             return names.fromUtf(externalize(t.tsym.flatName()));
 356         } else if (t.hasTag(ARRAY)) {
 357             return typeSig(types.erasure(t));
 358         } else {
 359             throw new AssertionError("xClassName expects class or array type, got " + t);
 360         }
 361     }
 362 
 363 /******************************************************************
 364  * Writing the Constant Pool
 365  ******************************************************************/
 366 
 367     /** Thrown when the constant pool is over full.
 368      */
 369     public static class PoolOverflow extends Exception {
 370         private static final long serialVersionUID = 0;
 371         public PoolOverflow() {}
 372     }
 373     public static class StringOverflow extends Exception {
 374         private static final long serialVersionUID = 0;
 375         public final String value;
 376         public StringOverflow(String s) {
 377             value = s;
 378         }
 379     }
 380 
 381     /** Write constant pool to pool buffer.
 382      *  Note: during writing, constant pool
 383      *  might grow since some parts of constants still need to be entered.
 384      */
 385     void writePool(Pool pool) throws PoolOverflow, StringOverflow {
 386         int poolCountIdx = poolbuf.length;
 387         poolbuf.appendChar(0);
 388         int i = 1;
 389         while (i < pool.pp) {
 390             Object value = pool.pool[i];
 391             Assert.checkNonNull(value);
 392             if (value instanceof Method || value instanceof Variable)
 393                 value = ((DelegatedSymbol)value).getUnderlyingSymbol();
 394 
 395             if (value instanceof MethodSymbol) {
 396                 MethodSymbol m = (MethodSymbol)value;
 397                 if (!m.isDynamic()) {
 398                     poolbuf.appendByte((m.owner.flags() & INTERFACE) != 0
 399                               ? CONSTANT_InterfaceMethodref
 400                               : CONSTANT_Methodref);
 401                     poolbuf.appendChar(pool.put(m.owner));
 402                     poolbuf.appendChar(pool.put(nameType(m)));
 403                 } else {
 404                     //invokedynamic
 405                     DynamicMethodSymbol dynSym = (DynamicMethodSymbol)m;
 406                     MethodHandle handle = new MethodHandle(dynSym.bsmKind, dynSym.bsm, types);
 407                     DynamicMethod.BootstrapMethodsKey key = new DynamicMethod.BootstrapMethodsKey(dynSym, types);
 408 
 409                     // Figure out the index for existing BSM; create a new BSM if no key
 410                     DynamicMethod.BootstrapMethodsValue val = bootstrapMethods.get(key);
 411                     if (val == null) {
 412                         int index = bootstrapMethods.size();
 413                         val = new DynamicMethod.BootstrapMethodsValue(handle, index);
 414                         bootstrapMethods.put(key, val);
 415                     }
 416 
 417                     //init cp entries
 418                     pool.put(names.BootstrapMethods);
 419                     pool.put(handle);
 420                     for (Object staticArg : dynSym.staticArgs) {
 421                         pool.put(staticArg);
 422                     }
 423                     poolbuf.appendByte(CONSTANT_InvokeDynamic);
 424                     poolbuf.appendChar(val.index);
 425                     poolbuf.appendChar(pool.put(nameType(dynSym)));
 426                 }
 427             } else if (value instanceof VarSymbol) {
 428                 VarSymbol v = (VarSymbol)value;
 429                 poolbuf.appendByte(CONSTANT_Fieldref);
 430                 poolbuf.appendChar(pool.put(v.owner));
 431                 poolbuf.appendChar(pool.put(nameType(v)));
 432             } else if (value instanceof Name) {
 433                 poolbuf.appendByte(CONSTANT_Utf8);
 434                 byte[] bs = ((Name)value).toUtf();
 435                 poolbuf.appendChar(bs.length);
 436                 poolbuf.appendBytes(bs, 0, bs.length);
 437                 if (bs.length > Pool.MAX_STRING_LENGTH)
 438                     throw new StringOverflow(value.toString());
 439             } else if (value instanceof ClassSymbol) {
 440                 ClassSymbol c = (ClassSymbol)value;
 441                 if (c.owner.kind == TYP) pool.put(c.owner);
 442                 poolbuf.appendByte(CONSTANT_Class);
 443                 if (c.type.hasTag(ARRAY)) {
 444                     poolbuf.appendChar(pool.put(typeSig(c.type)));
 445                 } else {
 446                     poolbuf.appendChar(pool.put(names.fromUtf(externalize(c.flatname))));
 447                     enterInner(c);
 448                 }
 449             } else if (value instanceof NameAndType) {
 450                 NameAndType nt = (NameAndType)value;
 451                 poolbuf.appendByte(CONSTANT_NameandType);
 452                 poolbuf.appendChar(pool.put(nt.name));
 453                 poolbuf.appendChar(pool.put(typeSig(nt.uniqueType.type)));
 454             } else if (value instanceof Integer) {
 455                 poolbuf.appendByte(CONSTANT_Integer);
 456                 poolbuf.appendInt(((Integer)value).intValue());
 457             } else if (value instanceof Long) {
 458                 poolbuf.appendByte(CONSTANT_Long);
 459                 poolbuf.appendLong(((Long)value).longValue());
 460                 i++;
 461             } else if (value instanceof Float) {
 462                 poolbuf.appendByte(CONSTANT_Float);
 463                 poolbuf.appendFloat(((Float)value).floatValue());
 464             } else if (value instanceof Double) {
 465                 poolbuf.appendByte(CONSTANT_Double);
 466                 poolbuf.appendDouble(((Double)value).doubleValue());
 467                 i++;
 468             } else if (value instanceof String) {
 469                 poolbuf.appendByte(CONSTANT_String);
 470                 poolbuf.appendChar(pool.put(names.fromString((String)value)));
 471             } else if (value instanceof UniqueType) {
 472                 Type type = ((UniqueType)value).type;
 473                 if (type.hasTag(METHOD)) {
 474                     poolbuf.appendByte(CONSTANT_MethodType);
 475                     poolbuf.appendChar(pool.put(typeSig((MethodType)type)));
 476                 } else {
 477                     Assert.check(type.hasTag(ARRAY));
 478                     poolbuf.appendByte(CONSTANT_Class);
 479                     poolbuf.appendChar(pool.put(xClassName(type)));
 480                 }
 481             } else if (value instanceof MethodHandle) {
 482                 MethodHandle ref = (MethodHandle)value;
 483                 poolbuf.appendByte(CONSTANT_MethodHandle);
 484                 poolbuf.appendByte(ref.refKind);
 485                 poolbuf.appendChar(pool.put(ref.refSym));
 486             } else if (value instanceof ModuleSymbol) {
 487                 ModuleSymbol m = (ModuleSymbol)value;
 488                 poolbuf.appendByte(CONSTANT_Module);
 489                 poolbuf.appendChar(pool.put(m.name));
 490             } else if (value instanceof PackageSymbol) {
 491                 PackageSymbol m = (PackageSymbol)value;
 492                 poolbuf.appendByte(CONSTANT_Package);
 493                 poolbuf.appendChar(pool.put(names.fromUtf(externalize(m.fullname))));
 494             } else {
 495                 Assert.error("writePool " + value);
 496             }
 497             i++;
 498         }
 499         if (pool.pp > Pool.MAX_ENTRIES)
 500             throw new PoolOverflow();
 501         putChar(poolbuf, poolCountIdx, pool.pp);
 502     }
 503 
 504     /** Given a symbol, return its name-and-type.
 505      */
 506     NameAndType nameType(Symbol sym) {
 507         return new NameAndType(sym.name, sym.externalType(types), types);
 508         // the NameAndType is generated from a symbol reference, and the
 509         // adjustment of adding an additional this$n parameter needs to be made.
 510     }
 511 
 512 /******************************************************************
 513  * Writing Attributes
 514  ******************************************************************/
 515 
 516     /** Write header for an attribute to data buffer and return
 517      *  position past attribute length index.
 518      */
 519     int writeAttr(Name attrName) {
 520         databuf.appendChar(pool.put(attrName));
 521         databuf.appendInt(0);
 522         return databuf.length;
 523     }
 524 
 525     /** Fill in attribute length.
 526      */
 527     void endAttr(int index) {
 528         putInt(databuf, index - 4, databuf.length - index);
 529     }
 530 
 531     /** Leave space for attribute count and return index for
 532      *  number of attributes field.
 533      */
 534     int beginAttrs() {
 535         databuf.appendChar(0);
 536         return databuf.length;
 537     }
 538 
 539     /** Fill in number of attributes.
 540      */
 541     void endAttrs(int index, int count) {
 542         putChar(databuf, index - 2, count);
 543     }
 544 
 545     /** Write the EnclosingMethod attribute if needed.
 546      *  Returns the number of attributes written (0 or 1).
 547      */
 548     int writeEnclosingMethodAttribute(ClassSymbol c) {
 549         return writeEnclosingMethodAttribute(names.EnclosingMethod, c);
 550     }
 551 
 552     /** Write the EnclosingMethod attribute with a specified name.
 553      *  Returns the number of attributes written (0 or 1).
 554      */
 555     protected int writeEnclosingMethodAttribute(Name attributeName, ClassSymbol c) {
 556         if (c.owner.kind != MTH && // neither a local class
 557             c.name != names.empty) // nor anonymous
 558             return 0;
 559 
 560         int alenIdx = writeAttr(attributeName);
 561         ClassSymbol enclClass = c.owner.enclClass();
 562         MethodSymbol enclMethod =
 563             (c.owner.type == null // local to init block
 564              || c.owner.kind != MTH) // or member init
 565             ? null
 566             : (MethodSymbol)c.owner;
 567         databuf.appendChar(pool.put(enclClass));
 568         databuf.appendChar(enclMethod == null ? 0 : pool.put(nameType(c.owner)));
 569         endAttr(alenIdx);
 570         return 1;
 571     }
 572 
 573     /** Write flag attributes; return number of attributes written.
 574      */
 575     int writeFlagAttrs(long flags) {
 576         int acount = 0;
 577         if ((flags & DEPRECATED) != 0) {
 578             int alenIdx = writeAttr(names.Deprecated);
 579             endAttr(alenIdx);
 580             acount++;
 581         }
 582         return acount;
 583     }
 584 
 585     /** Write member (field or method) attributes;
 586      *  return number of attributes written.
 587      */
 588     int writeMemberAttrs(Symbol sym) {
 589         int acount = writeFlagAttrs(sym.flags());
 590         long flags = sym.flags();
 591         if ((flags & (SYNTHETIC | BRIDGE)) != SYNTHETIC &&
 592             (flags & ANONCONSTR) == 0 &&
 593             (!types.isSameType(sym.type, sym.erasure(types)) ||
 594              signatureGen.hasTypeVar(sym.type.getThrownTypes()))) {
 595             // note that a local class with captured variables
 596             // will get a signature attribute
 597             int alenIdx = writeAttr(names.Signature);
 598             databuf.appendChar(pool.put(typeSig(sym.type)));
 599             endAttr(alenIdx);
 600             acount++;
 601         }
 602         acount += writeJavaAnnotations(sym.getRawAttributes());
 603         acount += writeTypeAnnotations(sym.getRawTypeAttributes(), false);
 604         return acount;
 605     }
 606 
 607     /**
 608      * Write method parameter names attribute.
 609      */
 610     int writeMethodParametersAttr(MethodSymbol m) {
 611         MethodType ty = m.externalType(types).asMethodType();
 612         final int allparams = ty.argtypes.size();
 613         if (m.params != null && allparams != 0) {
 614             final int attrIndex = writeAttr(names.MethodParameters);
 615             databuf.appendByte(allparams);
 616             // Write extra parameters first
 617             for (VarSymbol s : m.extraParams) {
 618                 final int flags =
 619                     ((int) s.flags() & (FINAL | SYNTHETIC | MANDATED)) |
 620                     ((int) m.flags() & SYNTHETIC);
 621                 databuf.appendChar(pool.put(s.name));
 622                 databuf.appendChar(flags);
 623             }
 624             // Now write the real parameters
 625             for (VarSymbol s : m.params) {
 626                 final int flags =
 627                     ((int) s.flags() & (FINAL | SYNTHETIC | MANDATED)) |
 628                     ((int) m.flags() & SYNTHETIC);
 629                 databuf.appendChar(pool.put(s.name));
 630                 databuf.appendChar(flags);
 631             }
 632             // Now write the captured locals
 633             for (VarSymbol s : m.capturedLocals) {
 634                 final int flags =
 635                     ((int) s.flags() & (FINAL | SYNTHETIC | MANDATED)) |
 636                     ((int) m.flags() & SYNTHETIC);
 637                 databuf.appendChar(pool.put(s.name));
 638                 databuf.appendChar(flags);
 639             }
 640             endAttr(attrIndex);
 641             return 1;
 642         } else
 643             return 0;
 644     }
 645 
 646 
 647     private void writeParamAnnotations(List<VarSymbol> params,
 648                                        RetentionPolicy retention) {
 649         for (VarSymbol s : params) {
 650             ListBuffer<Attribute.Compound> buf = new ListBuffer<>();
 651             for (Attribute.Compound a : s.getRawAttributes())
 652                 if (types.getRetention(a) == retention)
 653                     buf.append(a);
 654             databuf.appendChar(buf.length());
 655             for (Attribute.Compound a : buf)
 656                 writeCompoundAttribute(a);
 657         }
 658 
 659     }
 660 
 661     private void writeParamAnnotations(MethodSymbol m,
 662                                        RetentionPolicy retention) {
 663         databuf.appendByte(m.params.length());
 664         writeParamAnnotations(m.params, retention);
 665     }
 666 
 667     /** Write method parameter annotations;
 668      *  return number of attributes written.
 669      */
 670     int writeParameterAttrs(MethodSymbol m) {
 671         boolean hasVisible = false;
 672         boolean hasInvisible = false;
 673         if (m.params != null) {
 674             for (VarSymbol s : m.params) {
 675                 for (Attribute.Compound a : s.getRawAttributes()) {
 676                     switch (types.getRetention(a)) {
 677                     case SOURCE: break;
 678                     case CLASS: hasInvisible = true; break;
 679                     case RUNTIME: hasVisible = true; break;
 680                     default: // /* fail soft */ throw new AssertionError(vis);
 681                     }
 682                 }
 683             }
 684         }
 685 
 686         int attrCount = 0;
 687         if (hasVisible) {
 688             int attrIndex = writeAttr(names.RuntimeVisibleParameterAnnotations);
 689             writeParamAnnotations(m, RetentionPolicy.RUNTIME);
 690             endAttr(attrIndex);
 691             attrCount++;
 692         }
 693         if (hasInvisible) {
 694             int attrIndex = writeAttr(names.RuntimeInvisibleParameterAnnotations);
 695             writeParamAnnotations(m, RetentionPolicy.CLASS);
 696             endAttr(attrIndex);
 697             attrCount++;
 698         }
 699         return attrCount;
 700     }
 701 
 702 /**********************************************************************
 703  * Writing Java-language annotations (aka metadata, attributes)
 704  **********************************************************************/
 705 
 706     /** Write Java-language annotations; return number of JVM
 707      *  attributes written (zero or one).
 708      */
 709     int writeJavaAnnotations(List<Attribute.Compound> attrs) {
 710         if (attrs.isEmpty()) return 0;
 711         ListBuffer<Attribute.Compound> visibles = new ListBuffer<>();
 712         ListBuffer<Attribute.Compound> invisibles = new ListBuffer<>();
 713         for (Attribute.Compound a : attrs) {
 714             switch (types.getRetention(a)) {
 715             case SOURCE: break;
 716             case CLASS: invisibles.append(a); break;
 717             case RUNTIME: visibles.append(a); break;
 718             default: // /* fail soft */ throw new AssertionError(vis);
 719             }
 720         }
 721 
 722         int attrCount = 0;
 723         if (visibles.length() != 0) {
 724             int attrIndex = writeAttr(names.RuntimeVisibleAnnotations);
 725             databuf.appendChar(visibles.length());
 726             for (Attribute.Compound a : visibles)
 727                 writeCompoundAttribute(a);
 728             endAttr(attrIndex);
 729             attrCount++;
 730         }
 731         if (invisibles.length() != 0) {
 732             int attrIndex = writeAttr(names.RuntimeInvisibleAnnotations);
 733             databuf.appendChar(invisibles.length());
 734             for (Attribute.Compound a : invisibles)
 735                 writeCompoundAttribute(a);
 736             endAttr(attrIndex);
 737             attrCount++;
 738         }
 739         return attrCount;
 740     }
 741 
 742     int writeTypeAnnotations(List<Attribute.TypeCompound> typeAnnos, boolean inCode) {
 743         if (typeAnnos.isEmpty()) return 0;
 744 
 745         ListBuffer<Attribute.TypeCompound> visibles = new ListBuffer<>();
 746         ListBuffer<Attribute.TypeCompound> invisibles = new ListBuffer<>();
 747 
 748         for (Attribute.TypeCompound tc : typeAnnos) {
 749             if (tc.hasUnknownPosition()) {
 750                 boolean fixed = tc.tryFixPosition();
 751 
 752                 // Could we fix it?
 753                 if (!fixed) {
 754                     // This happens for nested types like @A Outer. @B Inner.
 755                     // For method parameters we get the annotation twice! Once with
 756                     // a valid position, once unknown.
 757                     // TODO: find a cleaner solution.
 758                     PrintWriter pw = log.getWriter(Log.WriterKind.ERROR);
 759                     pw.println("ClassWriter: Position UNKNOWN in type annotation: " + tc);
 760                     continue;
 761                 }
 762             }
 763 
 764             if (tc.position.type.isLocal() != inCode)
 765                 continue;
 766             if (!tc.position.emitToClassfile())
 767                 continue;
 768             switch (types.getRetention(tc)) {
 769             case SOURCE: break;
 770             case CLASS: invisibles.append(tc); break;
 771             case RUNTIME: visibles.append(tc); break;
 772             default: // /* fail soft */ throw new AssertionError(vis);
 773             }
 774         }
 775 
 776         int attrCount = 0;
 777         if (visibles.length() != 0) {
 778             int attrIndex = writeAttr(names.RuntimeVisibleTypeAnnotations);
 779             databuf.appendChar(visibles.length());
 780             for (Attribute.TypeCompound p : visibles)
 781                 writeTypeAnnotation(p);
 782             endAttr(attrIndex);
 783             attrCount++;
 784         }
 785 
 786         if (invisibles.length() != 0) {
 787             int attrIndex = writeAttr(names.RuntimeInvisibleTypeAnnotations);
 788             databuf.appendChar(invisibles.length());
 789             for (Attribute.TypeCompound p : invisibles)
 790                 writeTypeAnnotation(p);
 791             endAttr(attrIndex);
 792             attrCount++;
 793         }
 794 
 795         return attrCount;
 796     }
 797 
 798     /** A visitor to write an attribute including its leading
 799      *  single-character marker.
 800      */
 801     class AttributeWriter implements Attribute.Visitor {
 802         public void visitConstant(Attribute.Constant _value) {
 803             Object value = _value.value;
 804             switch (_value.type.getTag()) {
 805             case BYTE:
 806                 databuf.appendByte('B');
 807                 break;
 808             case CHAR:
 809                 databuf.appendByte('C');
 810                 break;
 811             case SHORT:
 812                 databuf.appendByte('S');
 813                 break;
 814             case INT:
 815                 databuf.appendByte('I');
 816                 break;
 817             case LONG:
 818                 databuf.appendByte('J');
 819                 break;
 820             case FLOAT:
 821                 databuf.appendByte('F');
 822                 break;
 823             case DOUBLE:
 824                 databuf.appendByte('D');
 825                 break;
 826             case BOOLEAN:
 827                 databuf.appendByte('Z');
 828                 break;
 829             case CLASS:
 830                 Assert.check(value instanceof String);
 831                 databuf.appendByte('s');
 832                 value = names.fromString(value.toString()); // CONSTANT_Utf8
 833                 break;
 834             default:
 835                 throw new AssertionError(_value.type);
 836             }
 837             databuf.appendChar(pool.put(value));
 838         }
 839         public void visitEnum(Attribute.Enum e) {
 840             databuf.appendByte('e');
 841             databuf.appendChar(pool.put(typeSig(e.value.type)));
 842             databuf.appendChar(pool.put(e.value.name));
 843         }
 844         public void visitClass(Attribute.Class clazz) {
 845             databuf.appendByte('c');
 846             databuf.appendChar(pool.put(typeSig(types.erasure(clazz.classType))));
 847         }
 848         public void visitCompound(Attribute.Compound compound) {
 849             databuf.appendByte('@');
 850             writeCompoundAttribute(compound);
 851         }
 852         public void visitError(Attribute.Error x) {
 853             throw new AssertionError(x);
 854         }
 855         public void visitArray(Attribute.Array array) {
 856             databuf.appendByte('[');
 857             databuf.appendChar(array.values.length);
 858             for (Attribute a : array.values) {
 859                 a.accept(this);
 860             }
 861         }
 862     }
 863     AttributeWriter awriter = new AttributeWriter();
 864 
 865     /** Write a compound attribute excluding the '@' marker. */
 866     void writeCompoundAttribute(Attribute.Compound c) {
 867         databuf.appendChar(pool.put(typeSig(c.type)));
 868         databuf.appendChar(c.values.length());
 869         for (Pair<Symbol.MethodSymbol,Attribute> p : c.values) {
 870             databuf.appendChar(pool.put(p.fst.name));
 871             p.snd.accept(awriter);
 872         }
 873     }
 874 
 875     void writeTypeAnnotation(Attribute.TypeCompound c) {
 876         writePosition(c.position);
 877         writeCompoundAttribute(c);
 878     }
 879 
 880     void writePosition(TypeAnnotationPosition p) {
 881         databuf.appendByte(p.type.targetTypeValue()); // TargetType tag is a byte
 882         switch (p.type) {
 883         // instanceof
 884         case INSTANCEOF:
 885         // new expression
 886         case NEW:
 887         // constructor/method reference receiver
 888         case CONSTRUCTOR_REFERENCE:
 889         case METHOD_REFERENCE:
 890             databuf.appendChar(p.offset);
 891             break;
 892         // local variable
 893         case LOCAL_VARIABLE:
 894         // resource variable
 895         case RESOURCE_VARIABLE:
 896             databuf.appendChar(p.lvarOffset.length);  // for table length
 897             for (int i = 0; i < p.lvarOffset.length; ++i) {
 898                 databuf.appendChar(p.lvarOffset[i]);
 899                 databuf.appendChar(p.lvarLength[i]);
 900                 databuf.appendChar(p.lvarIndex[i]);
 901             }
 902             break;
 903         // exception parameter
 904         case EXCEPTION_PARAMETER:
 905             databuf.appendChar(p.getExceptionIndex());
 906             break;
 907         // method receiver
 908         case METHOD_RECEIVER:
 909             // Do nothing
 910             break;
 911         // type parameter
 912         case CLASS_TYPE_PARAMETER:
 913         case METHOD_TYPE_PARAMETER:
 914             databuf.appendByte(p.parameter_index);
 915             break;
 916         // type parameter bound
 917         case CLASS_TYPE_PARAMETER_BOUND:
 918         case METHOD_TYPE_PARAMETER_BOUND:
 919             databuf.appendByte(p.parameter_index);
 920             databuf.appendByte(p.bound_index);
 921             break;
 922         // class extends or implements clause
 923         case CLASS_EXTENDS:
 924             databuf.appendChar(p.type_index);
 925             break;
 926         // throws
 927         case THROWS:
 928             databuf.appendChar(p.type_index);
 929             break;
 930         // method parameter
 931         case METHOD_FORMAL_PARAMETER:
 932             databuf.appendByte(p.parameter_index);
 933             break;
 934         // type cast
 935         case CAST:
 936         // method/constructor/reference type argument
 937         case CONSTRUCTOR_INVOCATION_TYPE_ARGUMENT:
 938         case METHOD_INVOCATION_TYPE_ARGUMENT:
 939         case CONSTRUCTOR_REFERENCE_TYPE_ARGUMENT:
 940         case METHOD_REFERENCE_TYPE_ARGUMENT:
 941             databuf.appendChar(p.offset);
 942             databuf.appendByte(p.type_index);
 943             break;
 944         // We don't need to worry about these
 945         case METHOD_RETURN:
 946         case FIELD:
 947             break;
 948         case UNKNOWN:
 949             throw new AssertionError("jvm.ClassWriter: UNKNOWN target type should never occur!");
 950         default:
 951             throw new AssertionError("jvm.ClassWriter: Unknown target type for position: " + p);
 952         }
 953 
 954         { // Append location data for generics/arrays.
 955             databuf.appendByte(p.location.size());
 956             java.util.List<Integer> loc = TypeAnnotationPosition.getBinaryFromTypePath(p.location);
 957             for (int i : loc)
 958                 databuf.appendByte((byte)i);
 959         }
 960     }
 961 
 962 /**********************************************************************
 963  * Writing module attributes
 964  **********************************************************************/
 965 
 966     /** Write the Module attribute if needed.
 967      *  Returns the number of attributes written (0 or 1).
 968      */
 969     int writeModuleAttribute(ClassSymbol c) {
 970         ModuleSymbol m = (ModuleSymbol) c.owner;
 971 
 972         int alenIdx = writeAttr(names.Module);
 973 
 974         databuf.appendChar(pool.put(m));
 975         databuf.appendChar(ModuleFlags.value(m.flags)); // module_flags
 976         databuf.appendChar(m.version != null ? pool.put(m.version) : 0);
 977 
 978         ListBuffer<RequiresDirective> requires = new ListBuffer<>();
 979         for (RequiresDirective r: m.requires) {
 980             if (!r.flags.contains(RequiresFlag.EXTRA))
 981                 requires.add(r);
 982         }
 983         databuf.appendChar(requires.size());
 984         for (RequiresDirective r: requires) {
 985             databuf.appendChar(pool.put(r.module));
 986             databuf.appendChar(RequiresFlag.value(r.flags));
 987             databuf.appendChar(r.module.version != null ? pool.put(r.module.version) : 0);
 988         }
 989 
 990         List<ExportsDirective> exports = m.exports;
 991         databuf.appendChar(exports.size());
 992         for (ExportsDirective e: exports) {
 993             databuf.appendChar(pool.put(e.packge));
 994             databuf.appendChar(ExportsFlag.value(e.flags));
 995             if (e.modules == null) {
 996                 databuf.appendChar(0);
 997             } else {
 998                 databuf.appendChar(e.modules.size());
 999                 for (ModuleSymbol msym: e.modules) {
1000                     databuf.appendChar(pool.put(msym));
1001                 }
1002             }
1003         }
1004 
1005         List<OpensDirective> opens = m.opens;
1006         databuf.appendChar(opens.size());
1007         for (OpensDirective o: opens) {
1008             databuf.appendChar(pool.put(o.packge));
1009             databuf.appendChar(OpensFlag.value(o.flags));
1010             if (o.modules == null) {
1011                 databuf.appendChar(0);
1012             } else {
1013                 databuf.appendChar(o.modules.size());
1014                 for (ModuleSymbol msym: o.modules) {
1015                     databuf.appendChar(pool.put(msym));
1016                 }
1017             }
1018         }
1019 
1020         List<UsesDirective> uses = m.uses;
1021         databuf.appendChar(uses.size());
1022         for (UsesDirective s: uses) {
1023             databuf.appendChar(pool.put(s.service));
1024         }
1025 
1026         // temporary fix to merge repeated provides clause for same service;
1027         // eventually this should be disallowed when analyzing the module,
1028         // so that each service type only appears once.
1029         Map<ClassSymbol, Set<ClassSymbol>> mergedProvides = new LinkedHashMap<>();
1030         for (ProvidesDirective p : m.provides) {
1031             mergedProvides.computeIfAbsent(p.service, s -> new LinkedHashSet<>()).addAll(p.impls);
1032         }
1033         databuf.appendChar(mergedProvides.size());
1034         mergedProvides.forEach((srvc, impls) -> {
1035             databuf.appendChar(pool.put(srvc));
1036             databuf.appendChar(impls.size());
1037             impls.forEach(impl -> databuf.appendChar(pool.put(impl)));
1038         });
1039 
1040         endAttr(alenIdx);
1041         return 1;
1042     }
1043 
1044 /**********************************************************************
1045  * Writing Objects
1046  **********************************************************************/
1047 
1048     /** Enter an inner class into the `innerClasses' set/queue.
1049      */
1050     void enterInner(ClassSymbol c) {
1051         if (c.type.isCompound()) {
1052             throw new AssertionError("Unexpected intersection type: " + c.type);
1053         }
1054         try {
1055             c.complete();
1056         } catch (CompletionFailure ex) {
1057             System.err.println("error: " + c + ": " + ex.getMessage());
1058             throw ex;
1059         }
1060         if (!c.type.hasTag(CLASS)) return; // arrays
1061         if (pool != null && // pool might be null if called from xClassName
1062             c.owner.enclClass() != null &&
1063             (innerClasses == null || !innerClasses.contains(c))) {
1064 //          log.errWriter.println("enter inner " + c);//DEBUG
1065             enterInner(c.owner.enclClass());
1066             pool.put(c);
1067             if (c.name != names.empty)
1068                 pool.put(c.name);
1069             if (innerClasses == null) {
1070                 innerClasses = new HashSet<>();
1071                 innerClassesQueue = new ListBuffer<>();
1072                 pool.put(names.InnerClasses);
1073             }
1074             innerClasses.add(c);
1075             innerClassesQueue.append(c);
1076         }
1077     }
1078 
1079     /** Write "inner classes" attribute.
1080      */
1081     void writeInnerClasses() {
1082         int alenIdx = writeAttr(names.InnerClasses);
1083         databuf.appendChar(innerClassesQueue.length());
1084         for (List<ClassSymbol> l = innerClassesQueue.toList();
1085              l.nonEmpty();
1086              l = l.tail) {
1087             ClassSymbol inner = l.head;
1088             inner.markAbstractIfNeeded(types);
1089             char flags = (char) adjustFlags(inner.flags_field);
1090             if ((flags & INTERFACE) != 0) flags |= ABSTRACT; // Interfaces are always ABSTRACT
1091             flags &= ~STRICTFP; //inner classes should not have the strictfp flag set.
1092             if (dumpInnerClassModifiers) {
1093                 PrintWriter pw = log.getWriter(Log.WriterKind.ERROR);
1094                 pw.println("INNERCLASS  " + inner.name);
1095                 pw.println("---" + flagNames(flags));
1096             }
1097             databuf.appendChar(pool.get(inner));
1098             databuf.appendChar(
1099                 inner.owner.kind == TYP && !inner.name.isEmpty() ? pool.get(inner.owner) : 0);
1100             databuf.appendChar(
1101                 !inner.name.isEmpty() ? pool.get(inner.name) : 0);
1102             databuf.appendChar(flags);
1103         }
1104         endAttr(alenIdx);
1105     }
1106 
1107     /**
1108      * Write NestMembers attribute (if needed)
1109      */
1110     int writeNestMembersIfNeeded(ClassSymbol csym) {
1111         ListBuffer<Symbol> nested = new ListBuffer<>();
1112         listNested(csym, nested);
1113         Set<Symbol> nestedUnique = new LinkedHashSet<>(nested);
1114         if (csym.owner.kind == PCK && !nestedUnique.isEmpty()) {
1115             int alenIdx = writeAttr(names.NestMembers);
1116             databuf.appendChar(nestedUnique.size());
1117             for (Symbol s : nestedUnique) {
1118                 databuf.appendChar(pool.put(s));
1119             }
1120             endAttr(alenIdx);
1121             return 1;
1122         }
1123         return 0;
1124     }
1125 
1126     /**
1127      * Write NestHost attribute (if needed)
1128      */
1129     int writeNestHostIfNeeded(ClassSymbol csym) {
1130         if (csym.owner.kind != PCK) {
1131             int alenIdx = writeAttr(names.NestHost);
1132             databuf.appendChar(pool.put(csym.outermostClass()));
1133             endAttr(alenIdx);
1134             return 1;
1135         }
1136         return 0;
1137     }
1138 
1139     private void listNested(Symbol sym, ListBuffer<Symbol> seen) {
1140         if (sym.kind != TYP) return;
1141         ClassSymbol csym = (ClassSymbol)sym;
1142         if (csym.owner.kind != PCK) {
1143             seen.add(csym);
1144         }
1145         if (csym.members() != null) {
1146             for (Symbol s : sym.members().getSymbols()) {
1147                 listNested(s, seen);
1148             }
1149         }
1150         if (csym.trans_local != null) {
1151             for (Symbol s : csym.trans_local) {
1152                 listNested(s, seen);
1153             }
1154         }
1155     }
1156 
1157     /** Write "bootstrapMethods" attribute.
1158      */
1159     void writeBootstrapMethods() {
1160         int alenIdx = writeAttr(names.BootstrapMethods);
1161         databuf.appendChar(bootstrapMethods.size());
1162         for (Map.Entry<DynamicMethod.BootstrapMethodsKey, DynamicMethod.BootstrapMethodsValue> entry : bootstrapMethods.entrySet()) {
1163             DynamicMethod.BootstrapMethodsKey bsmKey = entry.getKey();
1164             //write BSM handle
1165             databuf.appendChar(pool.get(entry.getValue().mh));
1166             Object[] uniqueArgs = bsmKey.getUniqueArgs();
1167             //write static args length
1168             databuf.appendChar(uniqueArgs.length);
1169             //write static args array
1170             for (Object o : uniqueArgs) {
1171                 databuf.appendChar(pool.get(o));
1172             }
1173         }
1174         endAttr(alenIdx);
1175     }
1176 
1177     /** Write field symbol, entering all references into constant pool.
1178      */
1179     void writeField(VarSymbol v) {
1180         int flags = adjustFlags(v.flags());
1181         databuf.appendChar(flags);
1182         if (dumpFieldModifiers) {
1183             PrintWriter pw = log.getWriter(Log.WriterKind.ERROR);
1184             pw.println("FIELD  " + v.name);
1185             pw.println("---" + flagNames(v.flags()));
1186         }
1187         databuf.appendChar(pool.put(v.name));
1188         databuf.appendChar(pool.put(typeSig(v.erasure(types))));
1189         int acountIdx = beginAttrs();
1190         int acount = 0;
1191         if (v.getConstValue() != null) {
1192             int alenIdx = writeAttr(names.ConstantValue);
1193             databuf.appendChar(pool.put(v.getConstValue()));
1194             endAttr(alenIdx);
1195             acount++;
1196         }
1197         acount += writeMemberAttrs(v);
1198         endAttrs(acountIdx, acount);
1199     }
1200 
1201     /** Write method symbol, entering all references into constant pool.
1202      */
1203     void writeMethod(MethodSymbol m) {
1204         int flags = adjustFlags(m.flags());
1205         databuf.appendChar(flags);
1206         if (dumpMethodModifiers) {
1207             PrintWriter pw = log.getWriter(Log.WriterKind.ERROR);
1208             pw.println("METHOD  " + m.name);
1209             pw.println("---" + flagNames(m.flags()));
1210         }
1211         databuf.appendChar(pool.put(m.name));
1212         databuf.appendChar(pool.put(typeSig(m.externalType(types))));
1213         int acountIdx = beginAttrs();
1214         int acount = 0;
1215         if (m.code != null) {
1216             int alenIdx = writeAttr(names.Code);
1217             writeCode(m.code);
1218             m.code = null; // to conserve space
1219             endAttr(alenIdx);
1220             acount++;
1221         }
1222         List<Type> thrown = m.erasure(types).getThrownTypes();
1223         if (thrown.nonEmpty()) {
1224             int alenIdx = writeAttr(names.Exceptions);
1225             databuf.appendChar(thrown.length());
1226             for (List<Type> l = thrown; l.nonEmpty(); l = l.tail)
1227                 databuf.appendChar(pool.put(l.head.tsym));
1228             endAttr(alenIdx);
1229             acount++;
1230         }
1231         if (m.defaultValue != null) {
1232             int alenIdx = writeAttr(names.AnnotationDefault);
1233             m.defaultValue.accept(awriter);
1234             endAttr(alenIdx);
1235             acount++;
1236         }
1237         if (options.isSet(PARAMETERS) && target.hasMethodParameters()) {
1238             if (!m.isLambdaMethod()) // Per JDK-8138729, do not emit parameters table for lambda bodies.
1239                 acount += writeMethodParametersAttr(m);
1240         }
1241         acount += writeMemberAttrs(m);
1242         if (!m.isLambdaMethod())
1243             acount += writeParameterAttrs(m);
1244         endAttrs(acountIdx, acount);
1245     }
1246 
1247     /** Write code attribute of method.
1248      */
1249     void writeCode(Code code) {
1250         databuf.appendChar(code.max_stack);
1251         databuf.appendChar(code.max_locals);
1252         databuf.appendInt(code.cp);
1253         databuf.appendBytes(code.code, 0, code.cp);
1254         databuf.appendChar(code.catchInfo.length());
1255         for (List<char[]> l = code.catchInfo.toList();
1256              l.nonEmpty();
1257              l = l.tail) {
1258             for (int i = 0; i < l.head.length; i++)
1259                 databuf.appendChar(l.head[i]);
1260         }
1261         int acountIdx = beginAttrs();
1262         int acount = 0;
1263 
1264         if (code.lineInfo.nonEmpty()) {
1265             int alenIdx = writeAttr(names.LineNumberTable);
1266             databuf.appendChar(code.lineInfo.length());
1267             for (List<char[]> l = code.lineInfo.reverse();
1268                  l.nonEmpty();
1269                  l = l.tail)
1270                 for (int i = 0; i < l.head.length; i++)
1271                     databuf.appendChar(l.head[i]);
1272             endAttr(alenIdx);
1273             acount++;
1274         }
1275 
1276         if (genCrt && (code.crt != null)) {
1277             CRTable crt = code.crt;
1278             int alenIdx = writeAttr(names.CharacterRangeTable);
1279             int crtIdx = beginAttrs();
1280             int crtEntries = crt.writeCRT(databuf, code.lineMap, log);
1281             endAttrs(crtIdx, crtEntries);
1282             endAttr(alenIdx);
1283             acount++;
1284         }
1285 
1286         // counter for number of generic local variables
1287         if (code.varDebugInfo && code.varBufferSize > 0) {
1288             int nGenericVars = 0;
1289             int alenIdx = writeAttr(names.LocalVariableTable);
1290             databuf.appendChar(code.getLVTSize());
1291             for (int i=0; i<code.varBufferSize; i++) {
1292                 Code.LocalVar var = code.varBuffer[i];
1293 
1294                 for (Code.LocalVar.Range r: var.aliveRanges) {
1295                     // write variable info
1296                     Assert.check(r.start_pc >= 0
1297                             && r.start_pc <= code.cp);
1298                     databuf.appendChar(r.start_pc);
1299                     Assert.check(r.length > 0
1300                             && (r.start_pc + r.length) <= code.cp);
1301                     databuf.appendChar(r.length);
1302                     VarSymbol sym = var.sym;
1303                     databuf.appendChar(pool.put(sym.name));
1304                     Type vartype = sym.erasure(types);
1305                     databuf.appendChar(pool.put(typeSig(vartype)));
1306                     databuf.appendChar(var.reg);
1307                     if (needsLocalVariableTypeEntry(var.sym.type)) {
1308                         nGenericVars++;
1309                     }
1310                 }
1311             }
1312             endAttr(alenIdx);
1313             acount++;
1314 
1315             if (nGenericVars > 0) {
1316                 alenIdx = writeAttr(names.LocalVariableTypeTable);
1317                 databuf.appendChar(nGenericVars);
1318                 int count = 0;
1319 
1320                 for (int i=0; i<code.varBufferSize; i++) {
1321                     Code.LocalVar var = code.varBuffer[i];
1322                     VarSymbol sym = var.sym;
1323                     if (!needsLocalVariableTypeEntry(sym.type))
1324                         continue;
1325                     for (Code.LocalVar.Range r : var.aliveRanges) {
1326                         // write variable info
1327                         databuf.appendChar(r.start_pc);
1328                         databuf.appendChar(r.length);
1329                         databuf.appendChar(pool.put(sym.name));
1330                         databuf.appendChar(pool.put(typeSig(sym.type)));
1331                         databuf.appendChar(var.reg);
1332                         count++;
1333                     }
1334                 }
1335                 Assert.check(count == nGenericVars);
1336                 endAttr(alenIdx);
1337                 acount++;
1338             }
1339         }
1340 
1341         if (code.stackMapBufferSize > 0) {
1342             if (debugstackmap) System.out.println("Stack map for " + code.meth);
1343             int alenIdx = writeAttr(code.stackMap.getAttributeName(names));
1344             writeStackMap(code);
1345             endAttr(alenIdx);
1346             acount++;
1347         }
1348 
1349         acount += writeTypeAnnotations(code.meth.getRawTypeAttributes(), true);
1350 
1351         endAttrs(acountIdx, acount);
1352     }
1353     //where
1354     private boolean needsLocalVariableTypeEntry(Type t) {
1355         //a local variable needs a type-entry if its type T is generic
1356         //(i.e. |T| != T) and if it's not an non-denotable type (non-denotable
1357         // types are not supported in signature attribute grammar!)
1358         return !types.isSameType(t, types.erasure(t)) &&
1359                 check.checkDenotable(t);
1360     }
1361 
1362     void writeStackMap(Code code) {
1363         int nframes = code.stackMapBufferSize;
1364         if (debugstackmap) System.out.println(" nframes = " + nframes);
1365         databuf.appendChar(nframes);
1366 
1367         switch (code.stackMap) {
1368         case CLDC:
1369             for (int i=0; i<nframes; i++) {
1370                 if (debugstackmap) System.out.print("  " + i + ":");
1371                 Code.StackMapFrame frame = code.stackMapBuffer[i];
1372 
1373                 // output PC
1374                 if (debugstackmap) System.out.print(" pc=" + frame.pc);
1375                 databuf.appendChar(frame.pc);
1376 
1377                 // output locals
1378                 int localCount = 0;
1379                 for (int j=0; j<frame.locals.length;
1380                      j += Code.width(frame.locals[j])) {
1381                     localCount++;
1382                 }
1383                 if (debugstackmap) System.out.print(" nlocals=" +
1384                                                     localCount);
1385                 databuf.appendChar(localCount);
1386                 for (int j=0; j<frame.locals.length;
1387                      j += Code.width(frame.locals[j])) {
1388                     if (debugstackmap) System.out.print(" local[" + j + "]=");
1389                     writeStackMapType(frame.locals[j]);
1390                 }
1391 
1392                 // output stack
1393                 int stackCount = 0;
1394                 for (int j=0; j<frame.stack.length;
1395                      j += Code.width(frame.stack[j])) {
1396                     stackCount++;
1397                 }
1398                 if (debugstackmap) System.out.print(" nstack=" +
1399                                                     stackCount);
1400                 databuf.appendChar(stackCount);
1401                 for (int j=0; j<frame.stack.length;
1402                      j += Code.width(frame.stack[j])) {
1403                     if (debugstackmap) System.out.print(" stack[" + j + "]=");
1404                     writeStackMapType(frame.stack[j]);
1405                 }
1406                 if (debugstackmap) System.out.println();
1407             }
1408             break;
1409         case JSR202: {
1410             Assert.checkNull(code.stackMapBuffer);
1411             for (int i=0; i<nframes; i++) {
1412                 if (debugstackmap) System.out.print("  " + i + ":");
1413                 StackMapTableFrame frame = code.stackMapTableBuffer[i];
1414                 frame.write(this);
1415                 if (debugstackmap) System.out.println();
1416             }
1417             break;
1418         }
1419         default:
1420             throw new AssertionError("Unexpected stackmap format value");
1421         }
1422     }
1423 
1424         //where
1425         void writeStackMapType(Type t) {
1426             if (t == null) {
1427                 if (debugstackmap) System.out.print("empty");
1428                 databuf.appendByte(0);
1429             }
1430             else switch(t.getTag()) {
1431             case BYTE:
1432             case CHAR:
1433             case SHORT:
1434             case INT:
1435             case BOOLEAN:
1436                 if (debugstackmap) System.out.print("int");
1437                 databuf.appendByte(1);
1438                 break;
1439             case FLOAT:
1440                 if (debugstackmap) System.out.print("float");
1441                 databuf.appendByte(2);
1442                 break;
1443             case DOUBLE:
1444                 if (debugstackmap) System.out.print("double");
1445                 databuf.appendByte(3);
1446                 break;
1447             case LONG:
1448                 if (debugstackmap) System.out.print("long");
1449                 databuf.appendByte(4);
1450                 break;
1451             case BOT: // null
1452                 if (debugstackmap) System.out.print("null");
1453                 databuf.appendByte(5);
1454                 break;
1455             case CLASS:
1456             case ARRAY:
1457                 if (debugstackmap) System.out.print("object(" + t + ")");
1458                 databuf.appendByte(7);
1459                 databuf.appendChar(pool.put(t));
1460                 break;
1461             case TYPEVAR:
1462                 if (debugstackmap) System.out.print("object(" + types.erasure(t).tsym + ")");
1463                 databuf.appendByte(7);
1464                 databuf.appendChar(pool.put(types.erasure(t).tsym));
1465                 break;
1466             case UNINITIALIZED_THIS:
1467                 if (debugstackmap) System.out.print("uninit_this");
1468                 databuf.appendByte(6);
1469                 break;
1470             case UNINITIALIZED_OBJECT:
1471                 { UninitializedType uninitType = (UninitializedType)t;
1472                 databuf.appendByte(8);
1473                 if (debugstackmap) System.out.print("uninit_object@" + uninitType.offset);
1474                 databuf.appendChar(uninitType.offset);
1475                 }
1476                 break;
1477             default:
1478                 throw new AssertionError();
1479             }
1480         }
1481 
1482     /** An entry in the JSR202 StackMapTable */
1483     abstract static class StackMapTableFrame {
1484         abstract int getFrameType();
1485 
1486         void write(ClassWriter writer) {
1487             int frameType = getFrameType();
1488             writer.databuf.appendByte(frameType);
1489             if (writer.debugstackmap) System.out.print(" frame_type=" + frameType);
1490         }
1491 
1492         static class SameFrame extends StackMapTableFrame {
1493             final int offsetDelta;
1494             SameFrame(int offsetDelta) {
1495                 this.offsetDelta = offsetDelta;
1496             }
1497             int getFrameType() {
1498                 return (offsetDelta < SAME_FRAME_SIZE) ? offsetDelta : SAME_FRAME_EXTENDED;
1499             }
1500             @Override
1501             void write(ClassWriter writer) {
1502                 super.write(writer);
1503                 if (getFrameType() == SAME_FRAME_EXTENDED) {
1504                     writer.databuf.appendChar(offsetDelta);
1505                     if (writer.debugstackmap){
1506                         System.out.print(" offset_delta=" + offsetDelta);
1507                     }
1508                 }
1509             }
1510         }
1511 
1512         static class SameLocals1StackItemFrame extends StackMapTableFrame {
1513             final int offsetDelta;
1514             final Type stack;
1515             SameLocals1StackItemFrame(int offsetDelta, Type stack) {
1516                 this.offsetDelta = offsetDelta;
1517                 this.stack = stack;
1518             }
1519             int getFrameType() {
1520                 return (offsetDelta < SAME_FRAME_SIZE) ?
1521                        (SAME_FRAME_SIZE + offsetDelta) :
1522                        SAME_LOCALS_1_STACK_ITEM_EXTENDED;
1523             }
1524             @Override
1525             void write(ClassWriter writer) {
1526                 super.write(writer);
1527                 if (getFrameType() == SAME_LOCALS_1_STACK_ITEM_EXTENDED) {
1528                     writer.databuf.appendChar(offsetDelta);
1529                     if (writer.debugstackmap) {
1530                         System.out.print(" offset_delta=" + offsetDelta);
1531                     }
1532                 }
1533                 if (writer.debugstackmap) {
1534                     System.out.print(" stack[" + 0 + "]=");
1535                 }
1536                 writer.writeStackMapType(stack);
1537             }
1538         }
1539 
1540         static class ChopFrame extends StackMapTableFrame {
1541             final int frameType;
1542             final int offsetDelta;
1543             ChopFrame(int frameType, int offsetDelta) {
1544                 this.frameType = frameType;
1545                 this.offsetDelta = offsetDelta;
1546             }
1547             int getFrameType() { return frameType; }
1548             @Override
1549             void write(ClassWriter writer) {
1550                 super.write(writer);
1551                 writer.databuf.appendChar(offsetDelta);
1552                 if (writer.debugstackmap) {
1553                     System.out.print(" offset_delta=" + offsetDelta);
1554                 }
1555             }
1556         }
1557 
1558         static class AppendFrame extends StackMapTableFrame {
1559             final int frameType;
1560             final int offsetDelta;
1561             final Type[] locals;
1562             AppendFrame(int frameType, int offsetDelta, Type[] locals) {
1563                 this.frameType = frameType;
1564                 this.offsetDelta = offsetDelta;
1565                 this.locals = locals;
1566             }
1567             int getFrameType() { return frameType; }
1568             @Override
1569             void write(ClassWriter writer) {
1570                 super.write(writer);
1571                 writer.databuf.appendChar(offsetDelta);
1572                 if (writer.debugstackmap) {
1573                     System.out.print(" offset_delta=" + offsetDelta);
1574                 }
1575                 for (int i=0; i<locals.length; i++) {
1576                      if (writer.debugstackmap) System.out.print(" locals[" + i + "]=");
1577                      writer.writeStackMapType(locals[i]);
1578                 }
1579             }
1580         }
1581 
1582         static class FullFrame extends StackMapTableFrame {
1583             final int offsetDelta;
1584             final Type[] locals;
1585             final Type[] stack;
1586             FullFrame(int offsetDelta, Type[] locals, Type[] stack) {
1587                 this.offsetDelta = offsetDelta;
1588                 this.locals = locals;
1589                 this.stack = stack;
1590             }
1591             int getFrameType() { return FULL_FRAME; }
1592             @Override
1593             void write(ClassWriter writer) {
1594                 super.write(writer);
1595                 writer.databuf.appendChar(offsetDelta);
1596                 writer.databuf.appendChar(locals.length);
1597                 if (writer.debugstackmap) {
1598                     System.out.print(" offset_delta=" + offsetDelta);
1599                     System.out.print(" nlocals=" + locals.length);
1600                 }
1601                 for (int i=0; i<locals.length; i++) {
1602                     if (writer.debugstackmap) System.out.print(" locals[" + i + "]=");
1603                     writer.writeStackMapType(locals[i]);
1604                 }
1605 
1606                 writer.databuf.appendChar(stack.length);
1607                 if (writer.debugstackmap) { System.out.print(" nstack=" + stack.length); }
1608                 for (int i=0; i<stack.length; i++) {
1609                     if (writer.debugstackmap) System.out.print(" stack[" + i + "]=");
1610                     writer.writeStackMapType(stack[i]);
1611                 }
1612             }
1613         }
1614 
1615        /** Compare this frame with the previous frame and produce
1616         *  an entry of compressed stack map frame. */
1617         static StackMapTableFrame getInstance(Code.StackMapFrame this_frame,
1618                                               int prev_pc,
1619                                               Type[] prev_locals,
1620                                               Types types) {
1621             Type[] locals = this_frame.locals;
1622             Type[] stack = this_frame.stack;
1623             int offset_delta = this_frame.pc - prev_pc - 1;
1624             if (stack.length == 1) {
1625                 if (locals.length == prev_locals.length
1626                     && compare(prev_locals, locals, types) == 0) {
1627                     return new SameLocals1StackItemFrame(offset_delta, stack[0]);
1628                 }
1629             } else if (stack.length == 0) {
1630                 int diff_length = compare(prev_locals, locals, types);
1631                 if (diff_length == 0) {
1632                     return new SameFrame(offset_delta);
1633                 } else if (-MAX_LOCAL_LENGTH_DIFF < diff_length && diff_length < 0) {
1634                     // APPEND
1635                     Type[] local_diff = new Type[-diff_length];
1636                     for (int i=prev_locals.length, j=0; i<locals.length; i++,j++) {
1637                         local_diff[j] = locals[i];
1638                     }
1639                     return new AppendFrame(SAME_FRAME_EXTENDED - diff_length,
1640                                            offset_delta,
1641                                            local_diff);
1642                 } else if (0 < diff_length && diff_length < MAX_LOCAL_LENGTH_DIFF) {
1643                     // CHOP
1644                     return new ChopFrame(SAME_FRAME_EXTENDED - diff_length,
1645                                          offset_delta);
1646                 }
1647             }
1648             // FULL_FRAME
1649             return new FullFrame(offset_delta, locals, stack);
1650         }
1651 
1652         static boolean isInt(Type t) {
1653             return (t.getTag().isStrictSubRangeOf(INT)  || t.hasTag(BOOLEAN));
1654         }
1655 
1656         static boolean isSameType(Type t1, Type t2, Types types) {
1657             if (t1 == null) { return t2 == null; }
1658             if (t2 == null) { return false; }
1659 
1660             if (isInt(t1) && isInt(t2)) { return true; }
1661 
1662             if (t1.hasTag(UNINITIALIZED_THIS)) {
1663                 return t2.hasTag(UNINITIALIZED_THIS);
1664             } else if (t1.hasTag(UNINITIALIZED_OBJECT)) {
1665                 if (t2.hasTag(UNINITIALIZED_OBJECT)) {
1666                     return ((UninitializedType)t1).offset == ((UninitializedType)t2).offset;
1667                 } else {
1668                     return false;
1669                 }
1670             } else if (t2.hasTag(UNINITIALIZED_THIS) || t2.hasTag(UNINITIALIZED_OBJECT)) {
1671                 return false;
1672             }
1673 
1674             return types.isSameType(t1, t2);
1675         }
1676 
1677         static int compare(Type[] arr1, Type[] arr2, Types types) {
1678             int diff_length = arr1.length - arr2.length;
1679             if (diff_length > MAX_LOCAL_LENGTH_DIFF || diff_length < -MAX_LOCAL_LENGTH_DIFF) {
1680                 return Integer.MAX_VALUE;
1681             }
1682             int len = (diff_length > 0) ? arr2.length : arr1.length;
1683             for (int i=0; i<len; i++) {
1684                 if (!isSameType(arr1[i], arr2[i], types)) {
1685                     return Integer.MAX_VALUE;
1686                 }
1687             }
1688             return diff_length;
1689         }
1690     }
1691 
1692     void writeFields(Scope s) {
1693         // process them in reverse sibling order;
1694         // i.e., process them in declaration order.
1695         List<VarSymbol> vars = List.nil();
1696         for (Symbol sym : s.getSymbols(NON_RECURSIVE)) {
1697             if (sym.kind == VAR) vars = vars.prepend((VarSymbol)sym);
1698         }
1699         while (vars.nonEmpty()) {
1700             writeField(vars.head);
1701             vars = vars.tail;
1702         }
1703     }
1704 
1705     void writeMethods(Scope s) {
1706         List<MethodSymbol> methods = List.nil();
1707         for (Symbol sym : s.getSymbols(NON_RECURSIVE)) {
1708             if (sym.kind == MTH && (sym.flags() & HYPOTHETICAL) == 0)
1709                 methods = methods.prepend((MethodSymbol)sym);
1710         }
1711         while (methods.nonEmpty()) {
1712             writeMethod(methods.head);
1713             methods = methods.tail;
1714         }
1715     }
1716 
1717     /** Emit a class file for a given class.
1718      *  @param c      The class from which a class file is generated.
1719      */
1720     public JavaFileObject writeClass(ClassSymbol c)
1721         throws IOException, PoolOverflow, StringOverflow
1722     {
1723         String name = (c.owner.kind == MDL ? c.name : c.flatname).toString();
1724         Location outLocn;
1725         if (multiModuleMode) {
1726             ModuleSymbol msym = c.owner.kind == MDL ? (ModuleSymbol) c.owner : c.packge().modle;
1727             outLocn = fileManager.getLocationForModule(CLASS_OUTPUT, msym.name.toString());
1728         } else {
1729             outLocn = CLASS_OUTPUT;
1730         }
1731         JavaFileObject outFile
1732             = fileManager.getJavaFileForOutput(outLocn,
1733                                                name,
1734                                                JavaFileObject.Kind.CLASS,
1735                                                c.sourcefile);
1736         OutputStream out = outFile.openOutputStream();
1737         try {
1738             writeClassFile(out, c);
1739             if (verbose)
1740                 log.printVerbose("wrote.file", outFile.getName());
1741             out.close();
1742             out = null;
1743         } finally {
1744             if (out != null) {
1745                 // if we are propagating an exception, delete the file
1746                 out.close();
1747                 outFile.delete();
1748                 outFile = null;
1749             }
1750         }
1751         return outFile; // may be null if write failed
1752     }
1753 
1754     /** Write class `c' to outstream `out'.
1755      */
1756     public void writeClassFile(OutputStream out, ClassSymbol c)
1757         throws IOException, PoolOverflow, StringOverflow {
1758         Assert.check((c.flags() & COMPOUND) == 0);
1759         databuf.reset();
1760         poolbuf.reset();
1761         signatureGen.reset();
1762         pool = c.pool;
1763         innerClasses = null;
1764         innerClassesQueue = null;
1765         bootstrapMethods = new LinkedHashMap<>();
1766 
1767         Type supertype = types.supertype(c.type);
1768         List<Type> interfaces = types.interfaces(c.type);
1769         List<Type> typarams = c.type.getTypeArguments();
1770 
1771         int flags;
1772         if (c.owner.kind == MDL) {
1773             flags = ACC_MODULE;
1774         } else {
1775             flags = adjustFlags(c.flags() & ~DEFAULT);
1776             if ((flags & PROTECTED) != 0) flags |= PUBLIC;
1777             flags = flags & ClassFlags & ~STRICTFP;
1778             if ((flags & INTERFACE) == 0) flags |= ACC_SUPER;
1779         }
1780 
1781         if (dumpClassModifiers) {
1782             PrintWriter pw = log.getWriter(Log.WriterKind.ERROR);
1783             pw.println();
1784             pw.println("CLASSFILE  " + c.getQualifiedName());
1785             pw.println("---" + flagNames(flags));
1786         }
1787         databuf.appendChar(flags);
1788 
1789         if (c.owner.kind == MDL) {
1790             PackageSymbol unnamed = ((ModuleSymbol) c.owner).unnamedPackage;
1791             databuf.appendChar(pool.put(new ClassSymbol(0, names.module_info, unnamed)));
1792         } else {
1793             databuf.appendChar(pool.put(c));
1794         }
1795         databuf.appendChar(supertype.hasTag(CLASS) ? pool.put(supertype.tsym) : 0);
1796         databuf.appendChar(interfaces.length());
1797         for (List<Type> l = interfaces; l.nonEmpty(); l = l.tail)
1798             databuf.appendChar(pool.put(l.head.tsym));
1799         int fieldsCount = 0;
1800         int methodsCount = 0;
1801         for (Symbol sym : c.members().getSymbols(NON_RECURSIVE)) {
1802             switch (sym.kind) {
1803             case VAR: fieldsCount++; break;
1804             case MTH: if ((sym.flags() & HYPOTHETICAL) == 0) methodsCount++;
1805                       break;
1806             case TYP: enterInner((ClassSymbol)sym); break;
1807             default : Assert.error();
1808             }
1809         }
1810 
1811         if (c.trans_local != null) {
1812             for (ClassSymbol local : c.trans_local) {
1813                 enterInner(local);
1814             }
1815         }
1816 
1817         databuf.appendChar(fieldsCount);
1818         writeFields(c.members());
1819         databuf.appendChar(methodsCount);
1820         writeMethods(c.members());
1821 
1822         int acountIdx = beginAttrs();
1823         int acount = 0;
1824 
1825         boolean sigReq =
1826             typarams.length() != 0 || supertype.allparams().length() != 0;
1827         for (List<Type> l = interfaces; !sigReq && l.nonEmpty(); l = l.tail)
1828             sigReq = l.head.allparams().length() != 0;
1829         if (sigReq) {
1830             int alenIdx = writeAttr(names.Signature);
1831             if (typarams.length() != 0) signatureGen.assembleParamsSig(typarams);
1832             signatureGen.assembleSig(supertype);
1833             for (List<Type> l = interfaces; l.nonEmpty(); l = l.tail)
1834                 signatureGen.assembleSig(l.head);
1835             databuf.appendChar(pool.put(signatureGen.toName()));
1836             signatureGen.reset();
1837             endAttr(alenIdx);
1838             acount++;
1839         }
1840 
1841         if (c.sourcefile != null && emitSourceFile) {
1842             int alenIdx = writeAttr(names.SourceFile);
1843             // WHM 6/29/1999: Strip file path prefix.  We do it here at
1844             // the last possible moment because the sourcefile may be used
1845             // elsewhere in error diagnostics. Fixes 4241573.
1846             //databuf.appendChar(c.pool.put(c.sourcefile));
1847             String simpleName = PathFileObject.getSimpleName(c.sourcefile);
1848             databuf.appendChar(c.pool.put(names.fromString(simpleName)));
1849             endAttr(alenIdx);
1850             acount++;
1851         }
1852 
1853         if (genCrt) {
1854             // Append SourceID attribute
1855             int alenIdx = writeAttr(names.SourceID);
1856             databuf.appendChar(c.pool.put(names.fromString(Long.toString(getLastModified(c.sourcefile)))));
1857             endAttr(alenIdx);
1858             acount++;
1859             // Append CompilationID attribute
1860             alenIdx = writeAttr(names.CompilationID);
1861             databuf.appendChar(c.pool.put(names.fromString(Long.toString(System.currentTimeMillis()))));
1862             endAttr(alenIdx);
1863             acount++;
1864         }
1865 
1866         acount += writeFlagAttrs(c.flags());
1867         acount += writeJavaAnnotations(c.getRawAttributes());
1868         acount += writeTypeAnnotations(c.getRawTypeAttributes(), false);
1869         acount += writeEnclosingMethodAttribute(c);
1870         if (c.owner.kind == MDL) {
1871             acount += writeModuleAttribute(c);
1872             acount += writeFlagAttrs(c.owner.flags() & ~DEPRECATED);
1873         }
1874         acount += writeExtraClassAttributes(c);
1875 
1876         poolbuf.appendInt(JAVA_MAGIC);
1877         if (preview.isEnabled()) {
1878             poolbuf.appendChar(ClassFile.PREVIEW_MINOR_VERSION);
1879         } else {
1880             poolbuf.appendChar(target.minorVersion);
1881         }
1882         poolbuf.appendChar(target.majorVersion);
1883 
1884         // TODO: Need to skip this for Modules - not sure where
1885         // that check really belongs, but this works.
1886         if (c.owner.kind != MDL) {
1887             if (target.hasNestmateAccess()) {
1888                 acount += writeNestMembersIfNeeded(c);
1889                 acount += writeNestHostIfNeeded(c);
1890             }
1891         }
1892 
1893         writePool(c.pool);
1894 
1895         if (innerClasses != null) {
1896             writeInnerClasses();
1897             acount++;
1898         }
1899 
1900         if (!bootstrapMethods.isEmpty()) {
1901             writeBootstrapMethods();
1902             acount++;
1903         }
1904 
1905         endAttrs(acountIdx, acount);
1906 
1907         poolbuf.appendBytes(databuf.elems, 0, databuf.length);
1908         out.write(poolbuf.elems, 0, poolbuf.length);
1909 
1910         pool = c.pool = null; // to conserve space
1911      }
1912 
1913     /**Allows subclasses to write additional class attributes
1914      *
1915      * @return the number of attributes written
1916      */
1917     protected int writeExtraClassAttributes(ClassSymbol c) {
1918         return 0;
1919     }
1920 
1921     int adjustFlags(final long flags) {
1922         int result = (int)flags;
1923 
1924         if ((flags & BRIDGE) != 0)
1925             result |= ACC_BRIDGE;
1926         if ((flags & VARARGS) != 0)
1927             result |= ACC_VARARGS;
1928         if ((flags & DEFAULT) != 0)
1929             result &= ~ABSTRACT;
1930         return result;
1931     }
1932 
1933     long getLastModified(FileObject filename) {
1934         long mod = 0;
1935         try {
1936             mod = filename.getLastModified();
1937         } catch (SecurityException e) {
1938             throw new AssertionError("CRT: couldn't get source file modification date: " + e.getMessage());
1939         }
1940         return mod;
1941     }
1942 }