1 /*
   2  * Copyright (c) 2012, 2017, 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.reflect;
  27 
  28 import java.lang.annotation.*;
  29 import java.util.Map;
  30 import java.util.Objects;
  31 import java.util.StringJoiner;
  32 
  33 import jdk.internal.misc.SharedSecrets;
  34 import sun.reflect.annotation.AnnotationParser;
  35 import sun.reflect.annotation.AnnotationSupport;
  36 import sun.reflect.annotation.TypeAnnotationParser;
  37 import sun.reflect.annotation.TypeAnnotation;
  38 import sun.reflect.generics.repository.ConstructorRepository;
  39 
  40 /**
  41  * A shared superclass for the common functionality of {@link Method}
  42  * and {@link Constructor}.
  43  *
  44  * @since 1.8
  45  */
  46 public abstract class Executable extends AccessibleObject
  47     implements Member, GenericDeclaration {
  48     /*
  49      * Only grant package-visibility to the constructor.
  50      */
  51     Executable() {}
  52 
  53     /**
  54      * Accessor method to allow code sharing
  55      */
  56     abstract byte[] getAnnotationBytes();
  57 
  58     /**
  59      * Does the Executable have generic information.
  60      */
  61     abstract boolean hasGenericInformation();
  62 
  63     abstract ConstructorRepository getGenericInfo();
  64 
  65     boolean equalParamTypes(Class<?>[] params1, Class<?>[] params2) {
  66         /* Avoid unnecessary cloning */
  67         if (params1.length == params2.length) {
  68             for (int i = 0; i < params1.length; i++) {
  69                 if (params1[i] != params2[i])
  70                     return false;
  71             }
  72             return true;
  73         }
  74         return false;
  75     }
  76 
  77     Annotation[][] parseParameterAnnotations(byte[] parameterAnnotations) {
  78         return AnnotationParser.parseParameterAnnotations(
  79                parameterAnnotations,
  80                SharedSecrets.getJavaLangAccess().
  81                getConstantPool(getDeclaringClass()),
  82                getDeclaringClass());
  83     }
  84 
  85     void printModifiersIfNonzero(StringBuilder sb, int mask, boolean isDefault) {
  86         int mod = getModifiers() & mask;
  87 
  88         if (mod != 0 && !isDefault) {
  89             sb.append(Modifier.toString(mod)).append(' ');
  90         } else {
  91             int access_mod = mod & Modifier.ACCESS_MODIFIERS;
  92             if (access_mod != 0)
  93                 sb.append(Modifier.toString(access_mod)).append(' ');
  94             if (isDefault)
  95                 sb.append("default ");
  96             mod = (mod & ~Modifier.ACCESS_MODIFIERS);
  97             if (mod != 0)
  98                 sb.append(Modifier.toString(mod)).append(' ');
  99         }
 100     }
 101 
 102     String sharedToString(int modifierMask,
 103                           boolean isDefault,
 104                           Class<?>[] parameterTypes,
 105                           Class<?>[] exceptionTypes) {
 106         try {
 107             StringBuilder sb = new StringBuilder();
 108 
 109             printModifiersIfNonzero(sb, modifierMask, isDefault);
 110             specificToStringHeader(sb);
 111             sb.append('(');
 112             StringJoiner sj = new StringJoiner(",");
 113             for (Class<?> parameterType : parameterTypes) {
 114                 sj.add(parameterType.getTypeName());
 115             }
 116             sb.append(sj.toString());
 117             sb.append(')');
 118 
 119             if (exceptionTypes.length > 0) {
 120                 StringJoiner joiner = new StringJoiner(",", " throws ", "");
 121                 for (Class<?> exceptionType : exceptionTypes) {
 122                     joiner.add(exceptionType.getTypeName());
 123                 }
 124                 sb.append(joiner.toString());
 125             }
 126             return sb.toString();
 127         } catch (Exception e) {
 128             return "<" + e + ">";
 129         }
 130     }
 131 
 132     /**
 133      * Generate toString header information specific to a method or
 134      * constructor.
 135      */
 136     abstract void specificToStringHeader(StringBuilder sb);
 137 
 138     String sharedToGenericString(int modifierMask, boolean isDefault) {
 139         try {
 140             StringBuilder sb = new StringBuilder();
 141 
 142             printModifiersIfNonzero(sb, modifierMask, isDefault);
 143 
 144             TypeVariable<?>[] typeparms = getTypeParameters();
 145             if (typeparms.length > 0) {
 146                 StringJoiner sj = new StringJoiner(",", "<", "> ");
 147                 for(TypeVariable<?> typeparm: typeparms) {
 148                     sj.add(typeparm.getTypeName());
 149                 }
 150                 sb.append(sj.toString());
 151             }
 152 
 153             specificToGenericStringHeader(sb);
 154 
 155             sb.append('(');
 156             StringJoiner sj = new StringJoiner(",");
 157             Type[] params = getGenericParameterTypes();
 158             for (int j = 0; j < params.length; j++) {
 159                 String param = params[j].getTypeName();
 160                 if (isVarArgs() && (j == params.length - 1)) // replace T[] with T...
 161                     param = param.replaceFirst("\\[\\]$", "...");
 162                 sj.add(param);
 163             }
 164             sb.append(sj.toString());
 165             sb.append(')');
 166 
 167             Type[] exceptionTypes = getGenericExceptionTypes();
 168             if (exceptionTypes.length > 0) {
 169                 StringJoiner joiner = new StringJoiner(",", " throws ", "");
 170                 for (Type exceptionType : exceptionTypes) {
 171                     joiner.add(exceptionType.getTypeName());
 172                 }
 173                 sb.append(joiner.toString());
 174             }
 175             return sb.toString();
 176         } catch (Exception e) {
 177             return "<" + e + ">";
 178         }
 179     }
 180 
 181     /**
 182      * Generate toGenericString header information specific to a
 183      * method or constructor.
 184      */
 185     abstract void specificToGenericStringHeader(StringBuilder sb);
 186 
 187     /**
 188      * Returns the {@code Class} object representing the class or interface
 189      * that declares the executable represented by this object.
 190      */
 191     public abstract Class<?> getDeclaringClass();
 192 
 193     /**
 194      * Returns the name of the executable represented by this object.
 195      */
 196     public abstract String getName();
 197 
 198     /**
 199      * Returns the Java language {@linkplain Modifier modifiers} for
 200      * the executable represented by this object.
 201      */
 202     public abstract int getModifiers();
 203 
 204     /**
 205      * Returns an array of {@code TypeVariable} objects that represent the
 206      * type variables declared by the generic declaration represented by this
 207      * {@code GenericDeclaration} object, in declaration order.  Returns an
 208      * array of length 0 if the underlying generic declaration declares no type
 209      * variables.
 210      *
 211      * @return an array of {@code TypeVariable} objects that represent
 212      *     the type variables declared by this generic declaration
 213      * @throws GenericSignatureFormatError if the generic
 214      *     signature of this generic declaration does not conform to
 215      *     the format specified in
 216      *     <cite>The Java&trade; Virtual Machine Specification</cite>
 217      */
 218     public abstract TypeVariable<?>[] getTypeParameters();
 219 
 220     // returns shared array of parameter types - must never give it out
 221     // to the untrusted code...
 222     abstract Class<?>[] getSharedParameterTypes();
 223 
 224     // returns shared array of exception types - must never give it out
 225     // to the untrusted code...
 226     abstract Class<?>[] getSharedExceptionTypes();
 227 
 228     /**
 229      * Returns an array of {@code Class} objects that represent the formal
 230      * parameter types, in declaration order, of the executable
 231      * represented by this object.  Returns an array of length
 232      * 0 if the underlying executable takes no parameters.
 233      *
 234      * @return the parameter types for the executable this object
 235      * represents
 236      */
 237     public abstract Class<?>[] getParameterTypes();
 238 
 239     /**
 240      * Returns the number of formal parameters (whether explicitly
 241      * declared or implicitly declared or neither) for the executable
 242      * represented by this object.
 243      *
 244      * @return The number of formal parameters for the executable this
 245      * object represents
 246      */
 247     public int getParameterCount() {
 248         throw new AbstractMethodError();
 249     }
 250 
 251     /**
 252      * Returns an array of {@code Type} objects that represent the formal
 253      * parameter types, in declaration order, of the executable represented by
 254      * this object. Returns an array of length 0 if the
 255      * underlying executable takes no parameters.
 256      *
 257      * <p>If a formal parameter type is a parameterized type,
 258      * the {@code Type} object returned for it must accurately reflect
 259      * the actual type parameters used in the source code.
 260      *
 261      * <p>If a formal parameter type is a type variable or a parameterized
 262      * type, it is created. Otherwise, it is resolved.
 263      *
 264      * @return an array of {@code Type}s that represent the formal
 265      *     parameter types of the underlying executable, in declaration order
 266      * @throws GenericSignatureFormatError
 267      *     if the generic method signature does not conform to the format
 268      *     specified in
 269      *     <cite>The Java&trade; Virtual Machine Specification</cite>
 270      * @throws TypeNotPresentException if any of the parameter
 271      *     types of the underlying executable refers to a non-existent type
 272      *     declaration
 273      * @throws MalformedParameterizedTypeException if any of
 274      *     the underlying executable's parameter types refer to a parameterized
 275      *     type that cannot be instantiated for any reason
 276      */
 277     public Type[] getGenericParameterTypes() {
 278         if (hasGenericInformation())
 279             return getGenericInfo().getParameterTypes();
 280         else
 281             return getParameterTypes();
 282     }
 283 
 284     /**
 285      * Behaves like {@code getGenericParameterTypes}, but returns type
 286      * information for all parameters, including synthetic parameters.
 287      */
 288     Type[] getAllGenericParameterTypes() {
 289         final boolean genericInfo = hasGenericInformation();
 290 
 291         // Easy case: we don't have generic parameter information.  In
 292         // this case, we just return the result of
 293         // getParameterTypes().
 294         if (!genericInfo) {
 295             return getParameterTypes();
 296         } else {
 297             final boolean realParamData = hasRealParameterData();
 298             final Type[] genericParamTypes = getGenericParameterTypes();
 299             final Type[] nonGenericParamTypes = getParameterTypes();
 300             final Type[] out = new Type[nonGenericParamTypes.length];
 301             final Parameter[] params = getParameters();
 302             int fromidx = 0;
 303             // If we have real parameter data, then we use the
 304             // synthetic and mandate flags to our advantage.
 305             if (realParamData) {
 306                 for (int i = 0; i < out.length; i++) {
 307                     final Parameter param = params[i];
 308                     if (param.isSynthetic() || param.isImplicit()) {
 309                         // If we hit a synthetic or mandated parameter,
 310                         // use the non generic parameter info.
 311                         out[i] = nonGenericParamTypes[i];
 312                     } else {
 313                         // Otherwise, use the generic parameter info.
 314                         out[i] = genericParamTypes[fromidx];
 315                         fromidx++;
 316                     }
 317                 }
 318             } else {
 319                 // Otherwise, use the non-generic parameter data.
 320                 // Without method parameter reflection data, we have
 321                 // no way to figure out which parameters are
 322                 // synthetic/mandated, thus, no way to match up the
 323                 // indexes.
 324                 return genericParamTypes.length == nonGenericParamTypes.length ?
 325                     genericParamTypes : nonGenericParamTypes;
 326             }
 327             return out;
 328         }
 329     }
 330 
 331     /**
 332      * Returns an array of {@code Parameter} objects that represent
 333      * all the parameters to the underlying executable represented by
 334      * this object.  Returns an array of length 0 if the executable
 335      * has no parameters.
 336      *
 337      * <p>The parameters of the underlying executable do not necessarily
 338      * have unique names, or names that are legal identifiers in the
 339      * Java programming language (JLS 3.8).
 340      *
 341      * @throws MalformedParametersException if the class file contains
 342      * a MethodParameters attribute that is improperly formatted.
 343      * @return an array of {@code Parameter} objects representing all
 344      * the parameters to the executable this object represents.
 345      */
 346     public Parameter[] getParameters() {
 347         // TODO: This may eventually need to be guarded by security
 348         // mechanisms similar to those in Field, Method, etc.
 349         //
 350         // Need to copy the cached array to prevent users from messing
 351         // with it.  Since parameters are immutable, we can
 352         // shallow-copy.
 353         return privateGetParameters().clone();
 354     }
 355 
 356     private Parameter[] synthesizeAllParams() {
 357         final int realparams = getParameterCount();
 358         final Parameter[] out = new Parameter[realparams];
 359         for (int i = 0; i < realparams; i++)
 360             // TODO: is there a way to synthetically derive the
 361             // modifiers?  Probably not in the general case, since
 362             // we'd have no way of knowing about them, but there
 363             // may be specific cases.
 364             out[i] = new Parameter("arg" + i, 0, this, i);
 365         return out;
 366     }
 367 
 368     private void verifyParameters(final Parameter[] parameters) {
 369         final int mask = Modifier.FINAL | Modifier.SYNTHETIC | Modifier.MANDATED;
 370 
 371         if (getParameterTypes().length != parameters.length)
 372             throw new MalformedParametersException("Wrong number of parameters in MethodParameters attribute");
 373 
 374         for (Parameter parameter : parameters) {
 375             final String name = parameter.getRealName();
 376             final int mods = parameter.getModifiers();
 377 
 378             if (name != null) {
 379                 if (name.isEmpty() || name.indexOf('.') != -1 ||
 380                     name.indexOf(';') != -1 || name.indexOf('[') != -1 ||
 381                     name.indexOf('/') != -1) {
 382                     throw new MalformedParametersException("Invalid parameter name \"" + name + "\"");
 383                 }
 384             }
 385 
 386             if (mods != (mods & mask)) {
 387                 throw new MalformedParametersException("Invalid parameter modifiers");
 388             }
 389         }
 390     }
 391 
 392     private Parameter[] privateGetParameters() {
 393         // Use tmp to avoid multiple writes to a volatile.
 394         Parameter[] tmp = parameters;
 395 
 396         if (tmp == null) {
 397 
 398             // Otherwise, go to the JVM to get them
 399             try {
 400                 tmp = getParameters0();
 401             } catch(IllegalArgumentException e) {
 402                 // Rethrow ClassFormatErrors
 403                 throw new MalformedParametersException("Invalid constant pool index");
 404             }
 405 
 406             // If we get back nothing, then synthesize parameters
 407             if (tmp == null) {
 408                 hasRealParameterData = false;
 409                 tmp = synthesizeAllParams();
 410             } else {
 411                 hasRealParameterData = true;
 412                 verifyParameters(tmp);
 413             }
 414 
 415             parameters = tmp;
 416         }
 417 
 418         return tmp;
 419     }
 420 
 421     boolean hasRealParameterData() {
 422         // If this somehow gets called before parameters gets
 423         // initialized, force it into existence.
 424         if (parameters == null) {
 425             privateGetParameters();
 426         }
 427         return hasRealParameterData;
 428     }
 429 
 430     private transient volatile boolean hasRealParameterData;
 431     private transient volatile Parameter[] parameters;
 432 
 433     private native Parameter[] getParameters0();
 434     native byte[] getTypeAnnotationBytes0();
 435 
 436     // Needed by reflectaccess
 437     byte[] getTypeAnnotationBytes() {
 438         return getTypeAnnotationBytes0();
 439     }
 440 
 441     /**
 442      * Returns an array of {@code Class} objects that represent the
 443      * types of exceptions declared to be thrown by the underlying
 444      * executable represented by this object.  Returns an array of
 445      * length 0 if the executable declares no exceptions in its {@code
 446      * throws} clause.
 447      *
 448      * @return the exception types declared as being thrown by the
 449      * executable this object represents
 450      */
 451     public abstract Class<?>[] getExceptionTypes();
 452 
 453     /**
 454      * Returns an array of {@code Type} objects that represent the
 455      * exceptions declared to be thrown by this executable object.
 456      * Returns an array of length 0 if the underlying executable declares
 457      * no exceptions in its {@code throws} clause.
 458      *
 459      * <p>If an exception type is a type variable or a parameterized
 460      * type, it is created. Otherwise, it is resolved.
 461      *
 462      * @return an array of Types that represent the exception types
 463      *     thrown by the underlying executable
 464      * @throws GenericSignatureFormatError
 465      *     if the generic method signature does not conform to the format
 466      *     specified in
 467      *     <cite>The Java&trade; Virtual Machine Specification</cite>
 468      * @throws TypeNotPresentException if the underlying executable's
 469      *     {@code throws} clause refers to a non-existent type declaration
 470      * @throws MalformedParameterizedTypeException if
 471      *     the underlying executable's {@code throws} clause refers to a
 472      *     parameterized type that cannot be instantiated for any reason
 473      */
 474     public Type[] getGenericExceptionTypes() {
 475         Type[] result;
 476         if (hasGenericInformation() &&
 477             ((result = getGenericInfo().getExceptionTypes()).length > 0))
 478             return result;
 479         else
 480             return getExceptionTypes();
 481     }
 482 
 483     /**
 484      * Returns a string describing this {@code Executable}, including
 485      * any type parameters.
 486      * @return a string describing this {@code Executable}, including
 487      * any type parameters
 488      */
 489     public abstract String toGenericString();
 490 
 491     /**
 492      * Returns {@code true} if this executable was declared to take a
 493      * variable number of arguments; returns {@code false} otherwise.
 494      *
 495      * @return {@code true} if an only if this executable was declared
 496      * to take a variable number of arguments.
 497      */
 498     public boolean isVarArgs()  {
 499         return (getModifiers() & Modifier.VARARGS) != 0;
 500     }
 501 
 502     /**
 503      * Returns {@code true} if this executable is a synthetic
 504      * construct; returns {@code false} otherwise.
 505      *
 506      * @return true if and only if this executable is a synthetic
 507      * construct as defined by
 508      * <cite>The Java&trade; Language Specification</cite>.
 509      * @jls 13.1 The Form of a Binary
 510      */
 511     public boolean isSynthetic() {
 512         return Modifier.isSynthetic(getModifiers());
 513     }
 514 
 515     /**
 516      * Returns an array of arrays of {@code Annotation}s that
 517      * represent the annotations on the formal parameters, in
 518      * declaration order, of the {@code Executable} represented by
 519      * this object.  Synthetic and mandated parameters (see
 520      * explanation below), such as the outer "this" parameter to an
 521      * inner class constructor will be represented in the returned
 522      * array.  If the executable has no parameters (meaning no formal,
 523      * no synthetic, and no mandated parameters), a zero-length array
 524      * will be returned.  If the {@code Executable} has one or more
 525      * parameters, a nested array of length zero is returned for each
 526      * parameter with no annotations. The annotation objects contained
 527      * in the returned arrays are serializable.  The caller of this
 528      * method is free to modify the returned arrays; it will have no
 529      * effect on the arrays returned to other callers.
 530      *
 531      * A compiler may add extra parameters that are implicitly
 532      * declared in source ("mandated"), as well as parameters that
 533      * are neither implicitly nor explicitly declared in source
 534      * ("synthetic") to the parameter list for a method.  See {@link
 535      * java.lang.reflect.Parameter} for more information.
 536      *
 537      * @see java.lang.reflect.Parameter
 538      * @see java.lang.reflect.Parameter#getAnnotations
 539      * @return an array of arrays that represent the annotations on
 540      *    the formal and implicit parameters, in declaration order, of
 541      *    the executable represented by this object
 542      */
 543     public abstract Annotation[][] getParameterAnnotations();
 544 
 545     Annotation[][] sharedGetParameterAnnotations(Class<?>[] parameterTypes,
 546                                                  byte[] parameterAnnotations) {
 547         int numParameters = parameterTypes.length;
 548         if (parameterAnnotations == null)
 549             return new Annotation[numParameters][0];
 550 
 551         Annotation[][] result = parseParameterAnnotations(parameterAnnotations);
 552 
 553         if (result.length != numParameters &&
 554             handleParameterNumberMismatch(result.length, numParameters)) {
 555             Annotation[][] tmp = new Annotation[result.length+1][];
 556             // Shift annotations down one to account for an implicit leading parameter
 557             System.arraycopy(result, 0, tmp, 1, result.length);
 558             tmp[0] = new Annotation[0];
 559             result = tmp;
 560         }
 561         return result;
 562     }
 563 
 564     abstract boolean handleParameterNumberMismatch(int resultLength, int numParameters);
 565 
 566     /**
 567      * {@inheritDoc}
 568      * @throws NullPointerException  {@inheritDoc}
 569      */
 570     public <T extends Annotation> T getAnnotation(Class<T> annotationClass) {
 571         Objects.requireNonNull(annotationClass);
 572         return annotationClass.cast(declaredAnnotations().get(annotationClass));
 573     }
 574 
 575     /**
 576      * {@inheritDoc}
 577      * @throws NullPointerException {@inheritDoc}
 578      */
 579     @Override
 580     public <T extends Annotation> T[] getAnnotationsByType(Class<T> annotationClass) {
 581         Objects.requireNonNull(annotationClass);
 582 
 583         return AnnotationSupport.getDirectlyAndIndirectlyPresent(declaredAnnotations(), annotationClass);
 584     }
 585 
 586     /**
 587      * {@inheritDoc}
 588      */
 589     public Annotation[] getDeclaredAnnotations()  {
 590         return AnnotationParser.toArray(declaredAnnotations());
 591     }
 592 
 593     private transient volatile Map<Class<? extends Annotation>, Annotation> declaredAnnotations;
 594 
 595     private Map<Class<? extends Annotation>, Annotation> declaredAnnotations() {
 596         Map<Class<? extends Annotation>, Annotation> declAnnos;
 597         if ((declAnnos = declaredAnnotations) == null) {
 598             synchronized (this) {
 599                 if ((declAnnos = declaredAnnotations) == null) {
 600                     Executable root = (Executable)getRoot();
 601                     if (root != null) {
 602                         declAnnos = root.declaredAnnotations();
 603                     } else {
 604                         declAnnos = AnnotationParser.parseAnnotations(
 605                                 getAnnotationBytes(),
 606                                 SharedSecrets.getJavaLangAccess().
 607                                         getConstantPool(getDeclaringClass()),
 608                                 getDeclaringClass()
 609                         );
 610                     }
 611                     declaredAnnotations = declAnnos;
 612                 }
 613             }
 614         }
 615         return declAnnos;
 616     }
 617 
 618     /**
 619      * Returns an {@code AnnotatedType} object that represents the use of a type to
 620      * specify the return type of the method/constructor represented by this
 621      * Executable.
 622      *
 623      * If this {@code Executable} object represents a constructor, the {@code
 624      * AnnotatedType} object represents the type of the constructed object.
 625      *
 626      * If this {@code Executable} object represents a method, the {@code
 627      * AnnotatedType} object represents the use of a type to specify the return
 628      * type of the method.
 629      *
 630      * @return an object representing the return type of the method
 631      * or constructor represented by this {@code Executable}
 632      */
 633     public abstract AnnotatedType getAnnotatedReturnType();
 634 
 635     /* Helper for subclasses of Executable.
 636      *
 637      * Returns an AnnotatedType object that represents the use of a type to
 638      * specify the return type of the method/constructor represented by this
 639      * Executable.
 640      */
 641     AnnotatedType getAnnotatedReturnType0(Type returnType) {
 642         return TypeAnnotationParser.buildAnnotatedType(getTypeAnnotationBytes0(),
 643                 SharedSecrets.getJavaLangAccess().
 644                         getConstantPool(getDeclaringClass()),
 645                 this,
 646                 getDeclaringClass(),
 647                 returnType,
 648                 TypeAnnotation.TypeAnnotationTarget.METHOD_RETURN);
 649     }
 650 
 651     /**
 652      * Returns an {@code AnnotatedType} object that represents the use of a
 653      * type to specify the receiver type of the method/constructor represented
 654      * by this {@code Executable} object.
 655      *
 656      * The receiver type of a method/constructor is available only if the
 657      * method/constructor has a receiver parameter (JLS 8.4.1). If this {@code
 658      * Executable} object <em>represents an instance method or represents a
 659      * constructor of an inner member class</em>, and the
 660      * method/constructor <em>either</em> has no receiver parameter or has a
 661      * receiver parameter with no annotations on its type, then the return
 662      * value is an {@code AnnotatedType} object representing an element with no
 663      * annotations.
 664      *
 665      * If this {@code Executable} object represents a static method or
 666      * represents a constructor of a top level, static member, local, or
 667      * anonymous class, then the return value is null.
 668      *
 669      * @return an object representing the receiver type of the method or
 670      * constructor represented by this {@code Executable} or {@code null} if
 671      * this {@code Executable} can not have a receiver parameter
 672      */
 673     public AnnotatedType getAnnotatedReceiverType() {
 674         if (Modifier.isStatic(this.getModifiers()))
 675             return null;
 676         return TypeAnnotationParser.buildAnnotatedType(getTypeAnnotationBytes0(),
 677                 SharedSecrets.getJavaLangAccess().
 678                         getConstantPool(getDeclaringClass()),
 679                 this,
 680                 getDeclaringClass(),
 681                 getDeclaringClass(),
 682                 TypeAnnotation.TypeAnnotationTarget.METHOD_RECEIVER);
 683     }
 684 
 685     /**
 686      * Returns an array of {@code AnnotatedType} objects that represent the use
 687      * of types to specify formal parameter types of the method/constructor
 688      * represented by this Executable. The order of the objects in the array
 689      * corresponds to the order of the formal parameter types in the
 690      * declaration of the method/constructor.
 691      *
 692      * Returns an array of length 0 if the method/constructor declares no
 693      * parameters.
 694      *
 695      * @return an array of objects representing the types of the
 696      * formal parameters of the method or constructor represented by this
 697      * {@code Executable}
 698      */
 699     public AnnotatedType[] getAnnotatedParameterTypes() {
 700         return TypeAnnotationParser.buildAnnotatedTypes(getTypeAnnotationBytes0(),
 701                 SharedSecrets.getJavaLangAccess().
 702                         getConstantPool(getDeclaringClass()),
 703                 this,
 704                 getDeclaringClass(),
 705                 getAllGenericParameterTypes(),
 706                 TypeAnnotation.TypeAnnotationTarget.METHOD_FORMAL_PARAMETER);
 707     }
 708 
 709     /**
 710      * Returns an array of {@code AnnotatedType} objects that represent the use
 711      * of types to specify the declared exceptions of the method/constructor
 712      * represented by this Executable. The order of the objects in the array
 713      * corresponds to the order of the exception types in the declaration of
 714      * the method/constructor.
 715      *
 716      * Returns an array of length 0 if the method/constructor declares no
 717      * exceptions.
 718      *
 719      * @return an array of objects representing the declared
 720      * exceptions of the method or constructor represented by this {@code
 721      * Executable}
 722      */
 723     public AnnotatedType[] getAnnotatedExceptionTypes() {
 724         return TypeAnnotationParser.buildAnnotatedTypes(getTypeAnnotationBytes0(),
 725                 SharedSecrets.getJavaLangAccess().
 726                         getConstantPool(getDeclaringClass()),
 727                 this,
 728                 getDeclaringClass(),
 729                 getGenericExceptionTypes(),
 730                 TypeAnnotation.TypeAnnotationTarget.THROWS);
 731     }
 732 
 733 }