1 /*
2 * Copyright (c) 2012, 2013, 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 java.lang.invoke;
27
28 import jdk.internal.org.objectweb.asm.*;
29 import sun.invoke.util.BytecodeDescriptor;
30 import sun.security.action.GetPropertyAction;
31 import sun.security.action.GetBooleanAction;
32
33 import java.io.FilePermission;
34 import java.io.Serializable;
35 import java.lang.invoke.MethodHandles.Lookup;
36 import java.lang.reflect.Constructor;
37 import java.lang.reflect.Modifier;
38 import java.security.AccessController;
39 import java.security.PrivilegedAction;
40 import java.util.LinkedHashSet;
41 import java.util.concurrent.atomic.AtomicInteger;
42 import java.util.PropertyPermission;
43 import java.util.Set;
44
45 import static java.lang.invoke.MethodHandles.Lookup.ClassOption.NESTMATE;
46 import static java.lang.invoke.MethodHandles.Lookup.ClassOption.STRONG;
47 import static jdk.internal.org.objectweb.asm.Opcodes.*;
48
49 /**
50 * Lambda metafactory implementation which dynamically creates an
51 * inner-class-like class per lambda callsite.
52 *
53 * @see LambdaMetafactory
54 */
55 /* package */ final class InnerClassLambdaMetafactory extends AbstractValidatingLambdaMetafactory {
56 private static final int CLASSFILE_VERSION = 52;
57 private static final String METHOD_DESCRIPTOR_VOID = Type.getMethodDescriptor(Type.VOID_TYPE);
58 private static final String JAVA_LANG_OBJECT = "java/lang/Object";
59 private static final String NAME_CTOR = "<init>";
60
61 //Serialization support
62 private static final String NAME_SERIALIZED_LAMBDA = "java/lang/invoke/SerializedLambda";
63 private static final String NAME_NOT_SERIALIZABLE_EXCEPTION = "java/io/NotSerializableException";
64 private static final String DESCR_METHOD_WRITE_REPLACE = "()Ljava/lang/Object;";
65 private static final String DESCR_METHOD_WRITE_OBJECT = "(Ljava/io/ObjectOutputStream;)V";
66 private static final String DESCR_METHOD_READ_OBJECT = "(Ljava/io/ObjectInputStream;)V";
67 private static final String DESCR_SET_IMPL_METHOD = "(Ljava/lang/invoke/MethodHandle;)V";
68
69 private static final String NAME_METHOD_WRITE_REPLACE = "writeReplace";
70 private static final String NAME_METHOD_READ_OBJECT = "readObject";
71 private static final String NAME_METHOD_WRITE_OBJECT = "writeObject";
72 private static final String NAME_FIELD_IMPL_METHOD = "protectedImplMethod";
73
74 private static final String DESCR_CLASS = "Ljava/lang/Class;";
75 private static final String DESCR_STRING = "Ljava/lang/String;";
76 private static final String DESCR_OBJECT = "Ljava/lang/Object;";
77 private static final String DESCR_METHOD_HANDLE = "Ljava/lang/invoke/MethodHandle;";
78 private static final String DESCR_CTOR_SERIALIZED_LAMBDA
79 = "(" + DESCR_CLASS + DESCR_STRING + DESCR_STRING + DESCR_STRING + "I"
80 + DESCR_STRING + DESCR_STRING + DESCR_STRING + DESCR_STRING + "[" + DESCR_OBJECT + ")V";
81
82 private static final String DESCR_CTOR_NOT_SERIALIZABLE_EXCEPTION = "(Ljava/lang/String;)V";
83 private static final String[] SER_HOSTILE_EXCEPTIONS = new String[] {NAME_NOT_SERIALIZABLE_EXCEPTION};
84
85 private static final String[] EMPTY_STRING_ARRAY = new String[0];
86
87 // Used to ensure that each spun class name is unique
88 private static final AtomicInteger counter = new AtomicInteger(0);
89
90 // For dumping generated classes to disk, for debugging purposes
91 private static final ProxyClassesDumper dumper;
92
93 private static final boolean disableEagerInitialization;
94
95 static {
96 final String dumpProxyClassesKey = "jdk.internal.lambda.dumpProxyClasses";
97 String dumpPath = GetPropertyAction.privilegedGetProperty(dumpProxyClassesKey);
98 dumper = (null == dumpPath) ? null : ProxyClassesDumper.getInstance(dumpPath);
99
100 final String disableEagerInitializationKey = "jdk.internal.lambda.disableEagerInitialization";
101 disableEagerInitialization = GetBooleanAction.privilegedGetProperty(disableEagerInitializationKey);
102 }
103
104 // See context values in AbstractValidatingLambdaMetafactory
105 private final String implMethodClassName; // Name of type containing implementation "CC"
106 private final String implMethodName; // Name of implementation method "impl"
107 private final String implMethodDesc; // Type descriptor for implementation methods "(I)Ljava/lang/String;"
108 private final MethodType constructorType; // Generated class constructor type "(CC)void"
109 private final ClassWriter cw; // ASM class writer
110 private final String[] argNames; // Generated names for the constructor arguments
111 private final String[] argDescs; // Type descriptors for the constructor arguments
112 private final String lambdaClassName; // Generated name for the generated class "X$$Lambda$1"
113 private final boolean useImplMethodHandle; // use MethodHandle invocation instead of symbolic bytecode invocation
114
115 /**
116 * General meta-factory constructor, supporting both standard cases and
117 * allowing for uncommon options such as serialization or bridging.
118 *
119 * @param caller Stacked automatically by VM; represents a lookup context
120 * with the accessibility privileges of the caller.
121 * @param invokedType Stacked automatically by VM; the signature of the
122 * invoked method, which includes the expected static
123 * type of the returned lambda object, and the static
124 * types of the captured arguments for the lambda. In
125 * the event that the implementation method is an
126 * instance method, the first argument in the invocation
127 * signature will correspond to the receiver.
128 * @param samMethodName Name of the method in the functional interface to
129 * which the lambda or method reference is being
130 * converted, represented as a String.
131 * @param samMethodType Type of the method in the functional interface to
132 * which the lambda or method reference is being
133 * converted, represented as a MethodType.
134 * @param implMethod The implementation method which should be called (with
135 * suitable adaptation of argument types, return types,
136 * and adjustment for captured arguments) when methods of
137 * the resulting functional interface instance are invoked.
138 * @param instantiatedMethodType The signature of the primary functional
139 * interface method after type variables are
140 * substituted with their instantiation from
141 * the capture site
142 * @param isSerializable Should the lambda be made serializable? If set,
143 * either the target type or one of the additional SAM
144 * types must extend {@code Serializable}.
145 * @param markerInterfaces Additional interfaces which the lambda object
146 * should implement.
147 * @param additionalBridges Method types for additional signatures to be
148 * bridged to the implementation method
149 * @throws LambdaConversionException If any of the meta-factory protocol
150 * invariants are violated
151 */
152 public InnerClassLambdaMetafactory(MethodHandles.Lookup caller,
153 MethodType invokedType,
154 String samMethodName,
155 MethodType samMethodType,
156 MethodHandle implMethod,
157 MethodType instantiatedMethodType,
158 boolean isSerializable,
159 Class<?>[] markerInterfaces,
160 MethodType[] additionalBridges)
161 throws LambdaConversionException {
162 super(caller, invokedType, samMethodName, samMethodType,
163 implMethod, instantiatedMethodType,
164 isSerializable, markerInterfaces, additionalBridges);
165 implMethodClassName = implClass.getName().replace('.', '/');
166 implMethodName = implInfo.getName();
167 implMethodDesc = implInfo.getMethodType().toMethodDescriptorString();
168 constructorType = invokedType.changeReturnType(Void.TYPE);
169 lambdaClassName = lambdaClassName(targetClass);
170 useImplMethodHandle = !implClass.getPackageName().equals(implInfo.getDeclaringClass().getPackageName())
171 && !Modifier.isPublic(implInfo.getModifiers());
172 cw = new ClassWriter(ClassWriter.COMPUTE_MAXS);
173 int parameterCount = invokedType.parameterCount();
174 if (parameterCount > 0) {
175 argNames = new String[parameterCount];
176 argDescs = new String[parameterCount];
177 for (int i = 0; i < parameterCount; i++) {
178 argNames[i] = "arg$" + (i + 1);
179 argDescs[i] = BytecodeDescriptor.unparse(invokedType.parameterType(i));
180 }
181 } else {
182 argNames = argDescs = EMPTY_STRING_ARRAY;
183 }
184 }
185
186 private static String lambdaClassName(Class<?> targetClass) {
187 String name = targetClass.getName();
188 if (targetClass.isHidden()) {
189 // use the original class name
190 name = name.replace('/', '_');
191 }
192 return name.replace('.', '/') + "$$Lambda$" + counter.incrementAndGet();
193 }
194
195 /**
196 * Build the CallSite. Generate a class file which implements the functional
197 * interface, define the class, if there are no parameters create an instance
198 * of the class which the CallSite will return, otherwise, generate handles
199 * which will call the class' constructor.
200 *
201 * @return a CallSite, which, when invoked, will return an instance of the
202 * functional interface
203 * @throws ReflectiveOperationException
204 * @throws LambdaConversionException If properly formed functional interface
205 * is not found
206 */
207 @Override
208 CallSite buildCallSite() throws LambdaConversionException {
209 final Class<?> innerClass = spinInnerClass();
210 if (invokedType.parameterCount() == 0 && !disableEagerInitialization) {
211 // In the case of a non-capturing lambda, we optimize linkage by pre-computing a single instance,
212 // unless we've suppressed eager initialization
213 final Constructor<?>[] ctrs = AccessController.doPrivileged(
214 new PrivilegedAction<>() {
215 @Override
216 public Constructor<?>[] run() {
217 Constructor<?>[] ctrs = innerClass.getDeclaredConstructors();
218 if (ctrs.length == 1) {
219 // The lambda implementing inner class constructor is private, set
220 // it accessible (by us) before creating the constant sole instance
221 ctrs[0].setAccessible(true);
222 }
223 return ctrs;
224 }
225 });
226 if (ctrs.length != 1) {
227 throw new LambdaConversionException("Expected one lambda constructor for "
228 + innerClass.getCanonicalName() + ", got " + ctrs.length);
229 }
230
231 try {
232 Object inst = ctrs[0].newInstance();
233 return new ConstantCallSite(MethodHandles.constant(samBase, inst));
234 } catch (ReflectiveOperationException e) {
235 throw new LambdaConversionException("Exception instantiating lambda object", e);
236 }
237 } else {
238 try {
239 MethodHandle mh = caller.findConstructor(innerClass, invokedType.changeReturnType(void.class));
240 return new ConstantCallSite(mh.asType(invokedType));
241 } catch (ReflectiveOperationException e) {
242 throw new LambdaConversionException("Exception finding constructor", e);
243 }
244 }
245 }
246
247 /**
248 * Generate a class file which implements the functional
249 * interface, define and return the class.
250 *
251 * @implNote The class that is generated does not include signature
252 * information for exceptions that may be present on the SAM method.
253 * This is to reduce classfile size, and is harmless as checked exceptions
254 * are erased anyway, no one will ever compile against this classfile,
255 * and we make no guarantees about the reflective properties of lambda
256 * objects.
257 *
258 * @return a Class which implements the functional interface
259 * @throws LambdaConversionException If properly formed functional interface
260 * is not found
261 */
262 private Class<?> spinInnerClass() throws LambdaConversionException {
263 String[] interfaces;
264 String samIntf = samBase.getName().replace('.', '/');
265 boolean accidentallySerializable = !isSerializable && Serializable.class.isAssignableFrom(samBase);
266 if (markerInterfaces.length == 0) {
267 interfaces = new String[]{samIntf};
268 } else {
269 // Assure no duplicate interfaces (ClassFormatError)
270 Set<String> itfs = new LinkedHashSet<>(markerInterfaces.length + 1);
271 itfs.add(samIntf);
272 for (Class<?> markerInterface : markerInterfaces) {
273 itfs.add(markerInterface.getName().replace('.', '/'));
274 accidentallySerializable |= !isSerializable && Serializable.class.isAssignableFrom(markerInterface);
275 }
276 interfaces = itfs.toArray(new String[itfs.size()]);
277 }
278
279 cw.visit(CLASSFILE_VERSION, ACC_SUPER + ACC_FINAL + ACC_SYNTHETIC,
280 lambdaClassName, null,
281 JAVA_LANG_OBJECT, interfaces);
282
283 // Generate final fields to be filled in by constructor
284 for (int i = 0; i < argDescs.length; i++) {
285 FieldVisitor fv = cw.visitField(ACC_PRIVATE + ACC_FINAL,
286 argNames[i],
287 argDescs[i],
288 null, null);
289 fv.visitEnd();
290 }
291
292 generateConstructor();
293
294 // Forward the SAM method
295 MethodVisitor mv = cw.visitMethod(ACC_PUBLIC, samMethodName,
296 samMethodType.toMethodDescriptorString(), null, null);
297 new ForwardingMethodGenerator(mv).generate(samMethodType);
298
299 // Forward the bridges
300 if (additionalBridges != null) {
301 for (MethodType mt : additionalBridges) {
302 mv = cw.visitMethod(ACC_PUBLIC|ACC_BRIDGE, samMethodName,
303 mt.toMethodDescriptorString(), null, null);
304 new ForwardingMethodGenerator(mv).generate(mt);
305 }
306 }
307
308 if (useImplMethodHandle) {
309 FieldVisitor fv = cw.visitField(ACC_PRIVATE + ACC_STATIC,
310 NAME_FIELD_IMPL_METHOD,
311 DESCR_METHOD_HANDLE,
312 null, null);
313 fv.visitEnd();
314 }
315
316 if (isSerializable)
317 generateSerializationFriendlyMethods();
318 else if (accidentallySerializable)
319 generateSerializationHostileMethods();
320
321 cw.visitEnd();
322
323 // Define the generated class in this VM.
324
325 final byte[] classBytes = cw.toByteArray();
326 // If requested, dump out to a file for debugging purposes
327 if (dumper != null) {
328 AccessController.doPrivileged(new PrivilegedAction<>() {
329 @Override
330 public Void run() {
331 dumper.dumpClass(lambdaClassName, classBytes);
332 return null;
333 }
334 }, null,
335 new FilePermission("<<ALL FILES>>", "read, write"),
336 // createDirectories may need it
337 new PropertyPermission("user.dir", "read"));
338 }
339 try {
340 // this class is linked at the indy callsite; so define a hidden nestmate
341 Lookup lookup = caller.defineHiddenClass(classBytes, !disableEagerInitialization, NESTMATE, STRONG);
342 if (useImplMethodHandle) {
343 // If the target class invokes a method reference this::m which is
344 // resolved to a protected method inherited from a superclass in a different
345 // package, the target class does not have a bridge and this method reference
346 // has been changed from public to protected after the target class was compiled.
347 // This lambda proxy class has no access to the resolved method.
348 // So this workaround by passing the live implMethod method handle
349 // to the proxy class to invoke directly.
350 MethodHandle mh = lookup.findStaticSetter(lookup.lookupClass(), NAME_FIELD_IMPL_METHOD, MethodHandle.class);
351 mh.invokeExact(implMethod);
352 }
353 return lookup.lookupClass();
354 } catch (IllegalAccessException e) {
355 throw new LambdaConversionException("Exception defining lambda proxy class", e);
356 } catch (Throwable t) {
357 throw new InternalError(t);
358 }
359 }
360
361 /**
362 * Generate the constructor for the class
363 */
364 private void generateConstructor() {
365 // Generate constructor
366 MethodVisitor ctor = cw.visitMethod(ACC_PRIVATE, NAME_CTOR,
367 constructorType.toMethodDescriptorString(), null, null);
368 ctor.visitCode();
369 ctor.visitVarInsn(ALOAD, 0);
370 ctor.visitMethodInsn(INVOKESPECIAL, JAVA_LANG_OBJECT, NAME_CTOR,
371 METHOD_DESCRIPTOR_VOID, false);
372 int parameterCount = invokedType.parameterCount();
373 for (int i = 0, lvIndex = 0; i < parameterCount; i++) {
374 ctor.visitVarInsn(ALOAD, 0);
375 Class<?> argType = invokedType.parameterType(i);
376 ctor.visitVarInsn(getLoadOpcode(argType), lvIndex + 1);
377 lvIndex += getParameterSize(argType);
378 ctor.visitFieldInsn(PUTFIELD, lambdaClassName, argNames[i], argDescs[i]);
379 }
380 ctor.visitInsn(RETURN);
381 // Maxs computed by ClassWriter.COMPUTE_MAXS, these arguments ignored
382 ctor.visitMaxs(-1, -1);
383 ctor.visitEnd();
384 }
385
386 /**
387 * Generate a writeReplace method that supports serialization
388 */
389 private void generateSerializationFriendlyMethods() {
390 TypeConvertingMethodAdapter mv
391 = new TypeConvertingMethodAdapter(
392 cw.visitMethod(ACC_PRIVATE + ACC_FINAL,
393 NAME_METHOD_WRITE_REPLACE, DESCR_METHOD_WRITE_REPLACE,
394 null, null));
395
396 mv.visitCode();
397 mv.visitTypeInsn(NEW, NAME_SERIALIZED_LAMBDA);
398 mv.visitInsn(DUP);
399 mv.visitLdcInsn(Type.getType(targetClass));
400 mv.visitLdcInsn(invokedType.returnType().getName().replace('.', '/'));
401 mv.visitLdcInsn(samMethodName);
402 mv.visitLdcInsn(samMethodType.toMethodDescriptorString());
403 mv.visitLdcInsn(implInfo.getReferenceKind());
404 mv.visitLdcInsn(implInfo.getDeclaringClass().getName().replace('.', '/'));
405 mv.visitLdcInsn(implInfo.getName());
406 mv.visitLdcInsn(implInfo.getMethodType().toMethodDescriptorString());
407 mv.visitLdcInsn(instantiatedMethodType.toMethodDescriptorString());
408 mv.iconst(argDescs.length);
409 mv.visitTypeInsn(ANEWARRAY, JAVA_LANG_OBJECT);
410 for (int i = 0; i < argDescs.length; i++) {
411 mv.visitInsn(DUP);
412 mv.iconst(i);
413 mv.visitVarInsn(ALOAD, 0);
414 mv.visitFieldInsn(GETFIELD, lambdaClassName, argNames[i], argDescs[i]);
415 mv.boxIfTypePrimitive(Type.getType(argDescs[i]));
416 mv.visitInsn(AASTORE);
417 }
418 mv.visitMethodInsn(INVOKESPECIAL, NAME_SERIALIZED_LAMBDA, NAME_CTOR,
419 DESCR_CTOR_SERIALIZED_LAMBDA, false);
420 mv.visitInsn(ARETURN);
421 // Maxs computed by ClassWriter.COMPUTE_MAXS, these arguments ignored
422 mv.visitMaxs(-1, -1);
423 mv.visitEnd();
424 }
425
426 /**
427 * Generate a readObject/writeObject method that is hostile to serialization
428 */
429 private void generateSerializationHostileMethods() {
430 MethodVisitor mv = cw.visitMethod(ACC_PRIVATE + ACC_FINAL,
431 NAME_METHOD_WRITE_OBJECT, DESCR_METHOD_WRITE_OBJECT,
432 null, SER_HOSTILE_EXCEPTIONS);
433 mv.visitCode();
434 mv.visitTypeInsn(NEW, NAME_NOT_SERIALIZABLE_EXCEPTION);
435 mv.visitInsn(DUP);
436 mv.visitLdcInsn("Non-serializable lambda");
437 mv.visitMethodInsn(INVOKESPECIAL, NAME_NOT_SERIALIZABLE_EXCEPTION, NAME_CTOR,
438 DESCR_CTOR_NOT_SERIALIZABLE_EXCEPTION, false);
439 mv.visitInsn(ATHROW);
440 mv.visitMaxs(-1, -1);
441 mv.visitEnd();
442
443 mv = cw.visitMethod(ACC_PRIVATE + ACC_FINAL,
444 NAME_METHOD_READ_OBJECT, DESCR_METHOD_READ_OBJECT,
445 null, SER_HOSTILE_EXCEPTIONS);
446 mv.visitCode();
447 mv.visitTypeInsn(NEW, NAME_NOT_SERIALIZABLE_EXCEPTION);
448 mv.visitInsn(DUP);
449 mv.visitLdcInsn("Non-serializable lambda");
450 mv.visitMethodInsn(INVOKESPECIAL, NAME_NOT_SERIALIZABLE_EXCEPTION, NAME_CTOR,
451 DESCR_CTOR_NOT_SERIALIZABLE_EXCEPTION, false);
452 mv.visitInsn(ATHROW);
453 mv.visitMaxs(-1, -1);
454 mv.visitEnd();
455 }
456
457 /**
458 * This class generates a method body which calls the lambda implementation
459 * method, converting arguments, as needed.
460 */
461 private class ForwardingMethodGenerator extends TypeConvertingMethodAdapter {
462
463 ForwardingMethodGenerator(MethodVisitor mv) {
464 super(mv);
465 }
466
467 void generate(MethodType methodType) {
468 visitCode();
469
470 if (implKind == MethodHandleInfo.REF_newInvokeSpecial) {
471 visitTypeInsn(NEW, implMethodClassName);
472 visitInsn(DUP);
473 }
474 if (useImplMethodHandle) {
475 visitVarInsn(ALOAD, 0);
476 visitFieldInsn(GETSTATIC, lambdaClassName, NAME_FIELD_IMPL_METHOD, DESCR_METHOD_HANDLE);
477 }
478 for (int i = 0; i < argNames.length; i++) {
479 visitVarInsn(ALOAD, 0);
480 visitFieldInsn(GETFIELD, lambdaClassName, argNames[i], argDescs[i]);
481 }
482
483 convertArgumentTypes(methodType);
484
485 if (useImplMethodHandle) {
486 MethodType mtype = implInfo.getMethodType().insertParameterTypes(0, implClass);
487 visitMethodInsn(INVOKEVIRTUAL, "java/lang/invoke/MethodHandle",
488 "invokeExact", mtype.descriptorString(), false);
489 } else {
490 // Invoke the method we want to forward to
491 visitMethodInsn(invocationOpcode(), implMethodClassName,
492 implMethodName, implMethodDesc,
493 implClass.isInterface());
494 }
495 // Convert the return value (if any) and return it
496 // Note: if adapting from non-void to void, the 'return'
497 // instruction will pop the unneeded result
498 Class<?> implReturnClass = implMethodType.returnType();
499 Class<?> samReturnClass = methodType.returnType();
500 convertType(implReturnClass, samReturnClass, samReturnClass);
501 visitInsn(getReturnOpcode(samReturnClass));
502 // Maxs computed by ClassWriter.COMPUTE_MAXS,these arguments ignored
503 visitMaxs(-1, -1);
504 visitEnd();
505 }
506
507 private void convertArgumentTypes(MethodType samType) {
508 int lvIndex = 0;
509 int samParametersLength = samType.parameterCount();
510 int captureArity = invokedType.parameterCount();
511 for (int i = 0; i < samParametersLength; i++) {
512 Class<?> argType = samType.parameterType(i);
513 visitVarInsn(getLoadOpcode(argType), lvIndex + 1);
514 lvIndex += getParameterSize(argType);
515 convertType(argType, implMethodType.parameterType(captureArity + i), instantiatedMethodType.parameterType(i));
516 }
517 }
518
519 private int invocationOpcode() throws InternalError {
520 switch (implKind) {
521 case MethodHandleInfo.REF_invokeStatic:
522 return INVOKESTATIC;
523 case MethodHandleInfo.REF_newInvokeSpecial:
524 return INVOKESPECIAL;
525 case MethodHandleInfo.REF_invokeVirtual:
526 return INVOKEVIRTUAL;
527 case MethodHandleInfo.REF_invokeInterface:
528 return INVOKEINTERFACE;
529 case MethodHandleInfo.REF_invokeSpecial:
530 return INVOKESPECIAL;
531 default:
532 throw new InternalError("Unexpected invocation kind: " + implKind);
533 }
534 }
535 }
536
537 static int getParameterSize(Class<?> c) {
538 if (c == Void.TYPE) {
539 return 0;
540 } else if (c == Long.TYPE || c == Double.TYPE) {
541 return 2;
542 }
543 return 1;
544 }
545
546 static int getLoadOpcode(Class<?> c) {
547 if(c == Void.TYPE) {
548 throw new InternalError("Unexpected void type of load opcode");
549 }
550 return ILOAD + getOpcodeOffset(c);
551 }
552
553 static int getReturnOpcode(Class<?> c) {
554 if(c == Void.TYPE) {
555 return RETURN;
556 }
557 return IRETURN + getOpcodeOffset(c);
558 }
559
560 private static int getOpcodeOffset(Class<?> c) {
561 if (c.isPrimitive()) {
562 if (c == Long.TYPE) {
563 return 1;
564 } else if (c == Float.TYPE) {
565 return 2;
566 } else if (c == Double.TYPE) {
567 return 3;
568 }
569 return 0;
570 } else {
571 return 4;
572 }
573 }
574
575 }