content: /*
   * Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
   * particular file as subject to the "Classpath" exception as provided
   * by Oracle in the LICENSE file that accompanied this code.
   *
   * This code is distributed in the hope that it will be useful, but WITHOUT
   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   * version 2 for more details (a copy is included in the LICENSE file that
   * accompanied this code).
   *
   * You should have received a copy of the GNU General Public License version
   * 2 along with this work; if not, write to the Free Software Foundation,
   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
   * or visit www.oracle.com if you need additional information or have any
   * questions.
   */
  
  package java.lang.reflect;
  
  import dalvik.annotation.optimization.FastNative;
  
  import java.lang.annotation.Annotation;
  import java.util.Objects;
  import libcore.reflect.AnnotatedElements;
  import libcore.reflect.GenericSignatureParser;
  import libcore.reflect.ListOfTypes;
  import libcore.reflect.Types;
  import libcore.util.EmptyArray;
  
  /**
   * A shared superclass for the common functionality of {@link Method}
   * and {@link Constructor}.
   *
   * @since 1.8
   */
  public abstract class Executable extends AccessibleObject
      implements Member, GenericDeclaration {
  
      // Android-changed: Extensive modifications made throughout the class for ART.
      // Android-removed: Declared vs actual parameter annotation indexes handling.
      // Android-removed: Type annotations runtime code. Not supported on Android.
  
      /*
       * Only grant package-visibility to the constructor.
       */
      Executable() {}
  
      /**
       * Does the Executable have generic information.
       */
      abstract boolean hasGenericInformation();
  
      boolean equalParamTypes(Class<?>[] params1, Class<?>[] params2) {
          /* Avoid unnecessary cloning */
          if (params1.length == params2.length) {
              for (int i = 0; i < params1.length; i++) {
                  if (params1[i] != params2[i])
                      return false;
              }
              return true;
          }
          return false;
      }
  
      void separateWithCommas(Class<?>[] types, StringBuilder sb) {
          for (int j = 0; j < types.length; j++) {
              sb.append(types[j].getTypeName());
              if (j < (types.length - 1))
                  sb.append(",");
          }
  
      }
  
      void printModifiersIfNonzero(StringBuilder sb, int mask, boolean isDefault) {
          int mod = getModifiers() & mask;
  
          if (mod != 0 && !isDefault) {
              sb.append(Modifier.toString(mod)).append(' ');
          } else {
              int access_mod = mod & Modifier.ACCESS_MODIFIERS;
              if (access_mod != 0)
                  sb.append(Modifier.toString(access_mod)).append(' ');
              if (isDefault)
                  sb.append("default ");
              mod = (mod & ~Modifier.ACCESS_MODIFIERS);
              if (mod != 0)
                  sb.append(Modifier.toString(mod)).append(' ');
          }
      }
  
      String sharedToString(int modifierMask,
                            boolean isDefault,
                            Class<?>[] parameterTypes,
                            Class<?>[] exceptionTypes) {
          try {
              StringBuilder sb = new StringBuilder();
  
              printModifiersIfNonzero(sb, modifierMask, isDefault);
              specificToStringHeader(sb);
  
              sb.append('(');
              separateWithCommas(parameterTypes, sb);
              sb.append(')');
              if (exceptionTypes.length > 0) {
                  sb.append(" throws ");
                  separateWithCommas(exceptionTypes, sb);
              }
              return sb.toString();
          } catch (Exception e) {
              return "<" + e + ">";
          }
      }
  
      /**
       * Generate toString header information specific to a method or
       * constructor.
       */
      abstract void specificToStringHeader(StringBuilder sb);
  
      String sharedToGenericString(int modifierMask, boolean isDefault) {
          try {
              StringBuilder sb = new StringBuilder();
  
              printModifiersIfNonzero(sb, modifierMask, isDefault);
  
              TypeVariable<?>[] typeparms = getTypeParameters();
              if (typeparms.length > 0) {
                  boolean first = true;
                  sb.append('<');
                  for(TypeVariable<?> typeparm: typeparms) {
                      if (!first)
                          sb.append(',');
                      // Class objects can't occur here; no need to test
                      // and call Class.getName().
                      sb.append(typeparm.toString());
                      first = false;
                  }
                  sb.append("> ");
              }
  
              specificToGenericStringHeader(sb);
  
              sb.append('(');
              Type[] params = getGenericParameterTypes();
              for (int j = 0; j < params.length; j++) {
                  String param = params[j].getTypeName();
                  if (isVarArgs() && (j == params.length - 1)) // replace T[] with T...
                      param = param.replaceFirst("\\[\\]$", "...");
                  sb.append(param);
                  if (j < (params.length - 1))
                      sb.append(',');
              }
              sb.append(')');
              Type[] exceptions = getGenericExceptionTypes();
              if (exceptions.length > 0) {
                  sb.append(" throws ");
                  for (int k = 0; k < exceptions.length; k++) {
                      sb.append((exceptions[k] instanceof Class)?
                                ((Class)exceptions[k]).getName():
                                exceptions[k].toString());
                      if (k < (exceptions.length - 1))
                          sb.append(',');
                  }
              }
              return sb.toString();
          } catch (Exception e) {
              return "<" + e + ">";
          }
      }
  
      /**
       * Generate toGenericString header information specific to a
       * method or constructor.
       */
      abstract void specificToGenericStringHeader(StringBuilder sb);
  
      /**
       * Returns the {@code Class} object representing the class or interface
       * that declares the executable represented by this object.
       */
      public abstract Class<?> getDeclaringClass();
  
      /**
       * Returns the name of the executable represented by this object.
       */
      public abstract String getName();
  
      /**
       * Returns the Java language {@linkplain Modifier modifiers} for
       * the executable represented by this object.
       */
      public abstract int getModifiers();
  
      /**
       * Returns an array of {@code TypeVariable} objects that represent the
       * type variables declared by the generic declaration represented by this
       * {@code GenericDeclaration} object, in declaration order.  Returns an
       * array of length 0 if the underlying generic declaration declares no type
       * variables.
       *
       * @return an array of {@code TypeVariable} objects that represent
       *     the type variables declared by this generic declaration
       * @throws GenericSignatureFormatError if the generic
       *     signature of this generic declaration does not conform to
       *     the format specified in
       *     <cite>The Java&trade; Virtual Machine Specification</cite>
       */
      public abstract TypeVariable<?>[] getTypeParameters();
  
      /**
       * Returns an array of {@code Class} objects that represent the formal
       * parameter types, in declaration order, of the executable
       * represented by this object.  Returns an array of length
       * 0 if the underlying executable takes no parameters.
       *
       * @return the parameter types for the executable this object
       * represents
       */
      public abstract Class<?>[] getParameterTypes();
  
      /**
       * Returns the number of formal parameters (whether explicitly
       * declared or implicitly declared or neither) for the executable
       * represented by this object.
       *
       * @return The number of formal parameters for the executable this
       * object represents
       */
      public int getParameterCount() {
          throw new AbstractMethodError();
      }
  
      /**
       * Returns an array of {@code Type} objects that represent the formal
       * parameter types, in declaration order, of the executable represented by
       * this object. Returns an array of length 0 if the
       * underlying executable takes no parameters.
       *
       * <p>If a formal parameter type is a parameterized type,
       * the {@code Type} object returned for it must accurately reflect
       * the actual type parameters used in the source code.
       *
       * <p>If a formal parameter type is a type variable or a parameterized
       * type, it is created. Otherwise, it is resolved.
       *
       * @return an array of {@code Type}s that represent the formal
       *     parameter types of the underlying executable, in declaration order
       * @throws GenericSignatureFormatError
       *     if the generic method signature does not conform to the format
       *     specified in
       *     <cite>The Java&trade; Virtual Machine Specification</cite>
       * @throws TypeNotPresentException if any of the parameter
       *     types of the underlying executable refers to a non-existent type
       *     declaration
       * @throws MalformedParameterizedTypeException if any of
       *     the underlying executable's parameter types refer to a parameterized
       *     type that cannot be instantiated for any reason
       */
      public Type[] getGenericParameterTypes() {
          // Android-changed: getGenericParameterTypes() implementation for use with ART.
          return Types.getTypeArray(
                  getMethodOrConstructorGenericInfoInternal().genericParameterTypes, false);
      }
  
      /**
       * Behaves like {@code getGenericParameterTypes}, but returns type
       * information for all parameters, including synthetic parameters.
       */
      Type[] getAllGenericParameterTypes() {
          final boolean genericInfo = hasGenericInformation();
  
          // Easy case: we don't have generic parameter information.  In
          // this case, we just return the result of
          // getParameterTypes().
          if (!genericInfo) {
              return getParameterTypes();
          } else {
              final boolean realParamData = hasRealParameterData();
              final Type[] genericParamTypes = getGenericParameterTypes();
              final Type[] nonGenericParamTypes = getParameterTypes();
              final Type[] out = new Type[nonGenericParamTypes.length];
              final Parameter[] params = getParameters();
              int fromidx = 0;
              // If we have real parameter data, then we use the
              // synthetic and mandate flags to our advantage.
              if (realParamData) {
                  for (int i = 0; i < out.length; i++) {
                      final Parameter param = params[i];
                      if (param.isSynthetic() || param.isImplicit()) {
                          // If we hit a synthetic or mandated parameter,
                          // use the non generic parameter info.
                          out[i] = nonGenericParamTypes[i];
                      } else {
                          // Otherwise, use the generic parameter info.
                          out[i] = genericParamTypes[fromidx];
                          fromidx++;
                      }
                  }
              } else {
                  // Otherwise, use the non-generic parameter data.
                  // Without method parameter reflection data, we have
                  // no way to figure out which parameters are
                  // synthetic/mandated, thus, no way to match up the
                  // indexes.
                  return genericParamTypes.length == nonGenericParamTypes.length ?
                      genericParamTypes : nonGenericParamTypes;
              }
              return out;
          }
      }
  
      /**
       * Returns an array of {@code Parameter} objects that represent
       * all the parameters to the underlying executable represented by
       * this object.  Returns an array of length 0 if the executable
       * has no parameters.
       *
       * <p>The parameters of the underlying executable do not necessarily
       * have unique names, or names that are legal identifiers in the
       * Java programming language (JLS 3.8).
       *
       * @throws MalformedParametersException if the class file contains
       * a MethodParameters attribute that is improperly formatted.
       * @return an array of {@code Parameter} objects representing all
       * the parameters to the executable this object represents.
       */
      public Parameter[] getParameters() {
          // TODO: This may eventually need to be guarded by security
          // mechanisms similar to those in Field, Method, etc.
          //
          // Need to copy the cached array to prevent users from messing
          // with it.  Since parameters are immutable, we can
          // shallow-copy.
          return privateGetParameters().clone();
      }
  
      private Parameter[] synthesizeAllParams() {
          final int realparams = getParameterCount();
          final Parameter[] out = new Parameter[realparams];
          for (int i = 0; i < realparams; i++)
              // TODO: is there a way to synthetically derive the
              // modifiers?  Probably not in the general case, since
              // we'd have no way of knowing about them, but there
              // may be specific cases.
              out[i] = new Parameter("arg" + i, 0, this, i);
          return out;
      }
  
      private void verifyParameters(final Parameter[] parameters) {
          final int mask = Modifier.FINAL | Modifier.SYNTHETIC | Modifier.MANDATED;
  
          if (getParameterTypes().length != parameters.length)
              throw new MalformedParametersException("Wrong number of parameters in MethodParameters attribute");
  
          for (Parameter parameter : parameters) {
              final String name = parameter.getRealName();
              final int mods = parameter.getModifiers();
  
              if (name != null) {
                  if (name.isEmpty() || name.indexOf('.') != -1 ||
                      name.indexOf(';') != -1 || name.indexOf('[') != -1 ||
                      name.indexOf('/') != -1) {
                      throw new MalformedParametersException("Invalid parameter name \"" + name + "\"");
                  }
              }
  
              if (mods != (mods & mask)) {
                  throw new MalformedParametersException("Invalid parameter modifiers");
              }
          }
      }
  
      private Parameter[] privateGetParameters() {
          // Use tmp to avoid multiple writes to a volatile.
          Parameter[] tmp = parameters;
  
          if (tmp == null) {
  
              // Otherwise, go to the JVM to get them
              try {
                  tmp = getParameters0();
              } catch(IllegalArgumentException e) {
                  // Rethrow ClassFormatErrors
                  // Android-changed: Exception changed to be more descriptive.
                  MalformedParametersException e2 =
                          new MalformedParametersException(
                                  "Invalid parameter metadata in class file");
                  e2.initCause(e);
                  throw e2;
              }
  
              // If we get back nothing, then synthesize parameters
              if (tmp == null) {
                  hasRealParameterData = false;
                  tmp = synthesizeAllParams();
              } else {
                  hasRealParameterData = true;
                  verifyParameters(tmp);
              }
  
              parameters = tmp;
          }
  
          return tmp;
      }
  
      boolean hasRealParameterData() {
          // If this somehow gets called before parameters gets
          // initialized, force it into existence.
          if (parameters == null) {
              privateGetParameters();
          }
          return hasRealParameterData;
      }
  
      private transient volatile boolean hasRealParameterData;
      private transient volatile Parameter[] parameters;
  
      // Android-changed: Added @FastNative to getParameters0()
      @FastNative
      private native Parameter[] getParameters0();
  
      /**
       * Returns an array of {@code Class} objects that represent the
       * types of exceptions declared to be thrown by the underlying
       * executable represented by this object.  Returns an array of
       * length 0 if the executable declares no exceptions in its {@code
       * throws} clause.
       *
       * @return the exception types declared as being thrown by the
       * executable this object represents
       */
      public abstract Class<?>[] getExceptionTypes();
  
      /**
       * Returns an array of {@code Type} objects that represent the
       * exceptions declared to be thrown by this executable object.
       * Returns an array of length 0 if the underlying executable declares
       * no exceptions in its {@code throws} clause.
       *
       * <p>If an exception type is a type variable or a parameterized
       * type, it is created. Otherwise, it is resolved.
       *
       * @return an array of Types that represent the exception types
       *     thrown by the underlying executable
       * @throws GenericSignatureFormatError
       *     if the generic method signature does not conform to the format
       *     specified in
       *     <cite>The Java&trade; Virtual Machine Specification</cite>
       * @throws TypeNotPresentException if the underlying executable's
       *     {@code throws} clause refers to a non-existent type declaration
       * @throws MalformedParameterizedTypeException if
       *     the underlying executable's {@code throws} clause refers to a
       *     parameterized type that cannot be instantiated for any reason
       */
      public Type[] getGenericExceptionTypes() {
          // Android-changed: getGenericExceptionTypes() implementation for use with ART.
          return Types.getTypeArray(
                  getMethodOrConstructorGenericInfoInternal().genericExceptionTypes, false);
      }
  
      /**
       * Returns a string describing this {@code Executable}, including
       * any type parameters.
       * @return a string describing this {@code Executable}, including
       * any type parameters
       */
      public abstract String toGenericString();
  
      /**
       * Returns {@code true} if this executable was declared to take a
       * variable number of arguments; returns {@code false} otherwise.
       *
       * @return {@code true} if an only if this executable was declared
       * to take a variable number of arguments.
       */
      public boolean isVarArgs()  {
          // Android-changed: isVarArgs() made slightly more efficient.
          return (accessFlags & Modifier.VARARGS) != 0;
      }
  
      /**
       * Returns {@code true} if this executable is a synthetic
       * construct; returns {@code false} otherwise.
       *
       * @return true if and only if this executable is a synthetic
       * construct as defined by
       * <cite>The Java&trade; Language Specification</cite>.
       * @jls 13.1 The Form of a Binary
       */
      public boolean isSynthetic() {
          // Android-changed: isSynthetic() made slightly more efficient.
          return (accessFlags & Modifier.SYNTHETIC) != 0;
      }
  
      /**
       * Returns an array of arrays of {@code Annotation}s that
       * represent the annotations on the formal parameters, in
       * declaration order, of the {@code Executable} represented by
       * this object.  Synthetic and mandated parameters (see
       * explanation below), such as the outer "this" parameter to an
       * inner class constructor will be represented in the returned
       * array.  If the executable has no parameters (meaning no formal,
       * no synthetic, and no mandated parameters), a zero-length array
       * will be returned.  If the {@code Executable} has one or more
       * parameters, a nested array of length zero is returned for each
       * parameter with no annotations. The annotation objects contained
       * in the returned arrays are serializable.  The caller of this
       * method is free to modify the returned arrays; it will have no
       * effect on the arrays returned to other callers.
       *
       * A compiler may add extra parameters that are implicitly
       * declared in source ("mandated"), as well as parameters that
       * are neither implicitly nor explicitly declared in source
       * ("synthetic") to the parameter list for a method.  See {@link
       * Parameter} for more information.
       *
       * @see Parameter
       * @see Parameter#getAnnotations
       * @return an array of arrays that represent the annotations on
       *    the formal and implicit parameters, in declaration order, of
       *    the executable represented by this object
       */
      public abstract Annotation[][] getParameterAnnotations();
  
      /**
       * {@inheritDoc}
       * @throws NullPointerException  {@inheritDoc}
       */
      public <T extends Annotation> T getAnnotation(Class<T> annotationClass) {
          Objects.requireNonNull(annotationClass);
          // Android-changed: Implemented getAnnotation(Class) natively.
          return getAnnotationNative(annotationClass);
      }
  
      // Android-changed: Implemented getAnnotation(Class) natively.
      @FastNative
      private native <T extends Annotation> T getAnnotationNative(Class<T> annotationClass);
  
      /**
       * {@inheritDoc}
       * @throws NullPointerException {@inheritDoc}
       */
      @Override
      public <T extends Annotation> T[] getAnnotationsByType(Class<T> annotationClass) {
          // Android-changed: getAnnotationsByType(Class), Android uses AnnotatedElements instead.
          return AnnotatedElements.getDirectOrIndirectAnnotationsByType(this, annotationClass);
      }
  
      /**
       * {@inheritDoc}
       */
      public Annotation[] getDeclaredAnnotations()  {
          // Android-changed: Implemented getDeclaredAnnotations() natively.
          return getDeclaredAnnotationsNative();
      }
  
      // Android-added: Implemented getDeclaredAnnotations() natively.
      @FastNative
      private native Annotation[] getDeclaredAnnotationsNative();
  
      // BEGIN Android-added: Additional ART-related fields and logic.
      // This code is shared for Method and Constructor.
  
      /** Bits encoding access (e.g. public, private) as well as other runtime specific flags */
      @SuppressWarnings("unused") // set by runtime
      private int accessFlags;
  
      /**
       * The ArtMethod associated with this Executable, required for dispatching due to entrypoints
       * Classloader is held live by the declaring class.
       */
      @SuppressWarnings("unused") // set by runtime
      private long artMethod;
  
      /** Executable's declaring class */
      @SuppressWarnings("unused") // set by runtime
      private Class<?> declaringClass;
  
      /**
       * Overriden method's declaring class (same as declaringClass unless declaringClass is a proxy
       * class).
       */
      @SuppressWarnings("unused") // set by runtime
      private Class<?> declaringClassOfOverriddenMethod;
  
      /** The method index of this method within its defining dex file */
      @SuppressWarnings("unused") // set by runtime
      private int dexMethodIndex;
  
      /**
       * We insert native method stubs for abstract methods so we don't have to
       * check the access flags at the time of the method call.  This results in
       * "native abstract" methods, which can't exist.  If we see the "abstract"
       * flag set, clear the "native" flag.
       *
       * We also move the DECLARED_SYNCHRONIZED flag into the SYNCHRONIZED
       * position, because the callers of this function are trying to convey
       * the "traditional" meaning of the flags to their callers.
       */
      private static int fixMethodFlags(int flags) {
          if ((flags & Modifier.ABSTRACT) != 0) {
              flags &= ~Modifier.NATIVE;
          }
          flags &= ~Modifier.SYNCHRONIZED;
          int ACC_DECLARED_SYNCHRONIZED = 0x00020000;
          if ((flags & ACC_DECLARED_SYNCHRONIZED) != 0) {
              flags |= Modifier.SYNCHRONIZED;
          }
          return flags & 0xffff;  // mask out bits not used by Java
      }
  
      final int getModifiersInternal() {
          return fixMethodFlags(accessFlags);
      }
  
      final Class<?> getDeclaringClassInternal() {
          return declaringClass;
      }
  
      /**
       * Returns an array of {@code Class} objects associated with the parameter types of this
       * Executable. If the Executable was declared with no parameters, {@code null} will be
       * returned.
       *
       * @return the parameter types, or {@code null} if no parameters were declared.
       */
      @FastNative
      final native Class<?>[] getParameterTypesInternal();
  
      @FastNative
      final native int getParameterCountInternal();
  
      // Android provides a more efficient implementation of this method for Executable than the one
      // implemented in AnnotatedElement.
      @Override
      public final boolean isAnnotationPresent(Class<? extends Annotation> annotationType) {
          Objects.requireNonNull(annotationType);
          return isAnnotationPresentNative(annotationType);
      }
      @FastNative
      private native boolean isAnnotationPresentNative(Class<? extends Annotation> annotationType);
  
      final Annotation[][] getParameterAnnotationsInternal() {
          Annotation[][] parameterAnnotations = getParameterAnnotationsNative();
          if (parameterAnnotations == null) {
              parameterAnnotations = new Annotation[getParameterTypes().length][0];
          }
          return parameterAnnotations;
      }
      @FastNative
      private native Annotation[][] getParameterAnnotationsNative();
  
      /**
       * @hide - exposed for use by {@link Class}.
       */
      public final int getAccessFlags() {
          return accessFlags;
      }
  
      /**
       * @hide - exposed for use by {@code java.lang.invoke.*}.
       */
      public final long getArtMethod() {
          return artMethod;
      }
  
      static final class GenericInfo {
          final ListOfTypes genericExceptionTypes;
          final ListOfTypes genericParameterTypes;
          final Type genericReturnType;
          final TypeVariable<?>[] formalTypeParameters;
  
          GenericInfo(ListOfTypes exceptions, ListOfTypes parameters, Type ret,
                  TypeVariable<?>[] formal) {
              genericExceptionTypes = exceptions;
              genericParameterTypes = parameters;
              genericReturnType = ret;
              formalTypeParameters = formal;
          }
      }
  
      final boolean hasGenericInformationInternal() {
          return getSignatureAnnotation() != null;
      }
  
      /**
       * Returns generic information associated with this method/constructor member.
       */
      final GenericInfo getMethodOrConstructorGenericInfoInternal() {
          String signatureAttribute = getSignatureAttribute();
          Class<?>[] exceptionTypes = this.getExceptionTypes();
          GenericSignatureParser parser =
                  new GenericSignatureParser(this.getDeclaringClass().getClassLoader());
          if (this instanceof Method) {
              parser.parseForMethod(this, signatureAttribute, exceptionTypes);
          } else {
              parser.parseForConstructor(this, signatureAttribute, exceptionTypes);
          }
          return new GenericInfo(parser.exceptionTypes, parser.parameterTypes,
                  parser.returnType, parser.formalTypeParameters);
      }
  
      private String getSignatureAttribute() {
          String[] annotation = getSignatureAnnotation();
          if (annotation == null) {
              return null;
          }
          StringBuilder result = new StringBuilder();
          for (String s : annotation) {
              result.append(s);
          }
          return result.toString();
      }
      @FastNative
      private native String[] getSignatureAnnotation();
  
      final boolean equalNameAndParametersInternal(Method m) {
          return getName().equals(m.getName()) && (compareMethodParametersInternal(m) == 0);
      }
  
      @FastNative
      native int compareMethodParametersInternal(Method meth);
  
      @FastNative
      final native String getMethodNameInternal();
  
      @FastNative
      final native Class<?> getMethodReturnTypeInternal();
  
      /** A cheap implementation for {@link Method#isDefault()}. */
      final boolean isDefaultMethodInternal() {
          return (accessFlags & Modifier.DEFAULT) != 0;
      }
  
      /** A cheap implementation for {@link Method#isBridge()}. */
      final boolean isBridgeMethodInternal() {
          return (accessFlags & Modifier.BRIDGE) != 0;
      }
      // END Android-added: Additional ART-related fields and logic.
  
  }
  