/*
   * Extract method arguments using unique key for parameterized methods
   * and type parameters for non-generic ones.
   */
  char[][] extractMethodArguments(IMethod method) {

    // Use bind key if the element is resolved
    if (method.isResolved()) {
      BindingKey bindingKey = new BindingKey(method.getKey());
      if (bindingKey.isParameterizedMethod()) {
        String[] argumentsSignatures = bindingKey.getTypeArguments();
        int length = argumentsSignatures.length;
        if (length > 0) {
          char[][] methodArguments = new char[length][];
          for (int i = 0; i < length; i++) {
            methodArguments[i] = argumentsSignatures[i].toCharArray();
            CharOperation.replace(methodArguments[i], new char[] {'$', '/'}, '.');
          }
          return methodArguments;
        }
      }
      return null;
    }

    // Try to get the argument using the JavaModel info
    try {
      ITypeParameter[] parameters = method.getTypeParameters();
      if (parameters != null) {
        int length = parameters.length;
        if (length > 0) {
          char[][] arguments = new char[length][];
          for (int i = 0; i < length; i++) {
            arguments[i] =
                Signature.createTypeSignature(parameters[i].getElementName(), false).toCharArray();
          }
          return arguments;
        }
      }
    } catch (JavaModelException jme) {
      // do nothing
    }
    return null;
  }
  /** Locate declaration in the current class file. This class file is always in a jar. */
  public void locateMatches(MatchLocator locator, ClassFile classFile, IBinaryType info)
      throws CoreException {
    SearchPattern pattern = locator.pattern;

    // check annotations references
    matchAnnotations(pattern, locator, classFile, info);

    // check class definition
    BinaryType binaryType = (BinaryType) classFile.getType();
    if (matchBinary(pattern, info, null)) {
      binaryType =
          new ResolvedBinaryType(
              (JavaElement) binaryType.getParent(),
              binaryType.getElementName(),
              binaryType.getKey());
      locator.reportBinaryMemberDeclaration(null, binaryType, null, info, SearchMatch.A_ACCURATE);
      return;
    }

    // Define arrays to store methods/fields from binary type if necessary
    IBinaryMethod[] binaryMethods = info.getMethods();
    int bMethodsLength = binaryMethods == null ? 0 : binaryMethods.length;
    IBinaryMethod[] unresolvedMethods = null;
    char[][] binaryMethodSignatures = null;
    boolean hasUnresolvedMethods = false;

    // Get fields from binary type info
    IBinaryField[] binaryFields = info.getFields();
    int bFieldsLength = binaryFields == null ? 0 : binaryFields.length;
    IBinaryField[] unresolvedFields = null;
    boolean hasUnresolvedFields = false;

    // Report as many accurate matches as possible
    int accuracy = SearchMatch.A_ACCURATE;
    boolean mustResolve = pattern.mustResolve;
    if (mustResolve) {
      BinaryTypeBinding binding = locator.cacheBinaryType(binaryType, info);
      if (binding != null) {
        // filter out element not in hierarchy scope
        if (!locator.typeInHierarchy(binding)) return;

        // Search matches on resolved methods
        MethodBinding[] availableMethods = binding.availableMethods();
        int aMethodsLength = availableMethods == null ? 0 : availableMethods.length;
        hasUnresolvedMethods = bMethodsLength != aMethodsLength;
        for (int i = 0; i < aMethodsLength; i++) {
          MethodBinding method = availableMethods[i];
          char[] methodSignature = method.genericSignature();
          if (methodSignature == null) methodSignature = method.signature();

          // Report the match if possible
          int level = locator.patternLocator.resolveLevel(method);
          if (level != PatternLocator.IMPOSSIBLE_MATCH) {
            IMethod methodHandle =
                binaryType.getMethod(
                    new String(
                        method.isConstructor()
                            ? binding.compoundName[binding.compoundName.length - 1]
                            : method.selector),
                    CharOperation.toStrings(
                        Signature.getParameterTypes(convertClassFileFormat(methodSignature))));
            accuracy =
                level == PatternLocator.ACCURATE_MATCH
                    ? SearchMatch.A_ACCURATE
                    : SearchMatch.A_INACCURATE;
            locator.reportBinaryMemberDeclaration(null, methodHandle, method, info, accuracy);
          }

          // Remove method from unresolved list
          if (hasUnresolvedMethods) {
            if (binaryMethodSignatures
                == null) { // Store binary method signatures to avoid multiple computation
              binaryMethodSignatures = new char[bMethodsLength][];
              for (int j = 0; j < bMethodsLength; j++) {
                IBinaryMethod binaryMethod = binaryMethods[j];
                char[] signature = binaryMethod.getGenericSignature();
                if (signature == null) signature = binaryMethod.getMethodDescriptor();
                binaryMethodSignatures[j] = signature;
              }
            }
            for (int j = 0; j < bMethodsLength; j++) {
              if (CharOperation.equals(binaryMethods[j].getSelector(), method.selector)
                  && CharOperation.equals(binaryMethodSignatures[j], methodSignature)) {
                if (unresolvedMethods == null) {
                  System.arraycopy(
                      binaryMethods,
                      0,
                      unresolvedMethods = new IBinaryMethod[bMethodsLength],
                      0,
                      bMethodsLength);
                }
                unresolvedMethods[j] = null;
                break;
              }
            }
          }
        }

        // Search matches on resolved fields
        FieldBinding[] availableFields = binding.availableFields();
        int aFieldsLength = availableFields == null ? 0 : availableFields.length;
        hasUnresolvedFields = bFieldsLength != aFieldsLength;
        for (int i = 0; i < aFieldsLength; i++) {
          FieldBinding field = availableFields[i];

          // Report the match if possible
          int level = locator.patternLocator.resolveLevel(field);
          if (level != PatternLocator.IMPOSSIBLE_MATCH) {
            IField fieldHandle = binaryType.getField(new String(field.name));
            accuracy =
                level == PatternLocator.ACCURATE_MATCH
                    ? SearchMatch.A_ACCURATE
                    : SearchMatch.A_INACCURATE;
            locator.reportBinaryMemberDeclaration(null, fieldHandle, field, info, accuracy);
          }

          // Remove the field from unresolved list
          if (hasUnresolvedFields) {
            for (int j = 0; j < bFieldsLength; j++) {
              if (CharOperation.equals(binaryFields[j].getName(), field.name)) {
                if (unresolvedFields == null) {
                  System.arraycopy(
                      binaryFields,
                      0,
                      unresolvedFields = new IBinaryField[bFieldsLength],
                      0,
                      bFieldsLength);
                }
                unresolvedFields[j] = null;
                break;
              }
            }
          }
        }

        // If all methods/fields were accurate then returns now
        if (!hasUnresolvedMethods && !hasUnresolvedFields) {
          return;
        }
      }
      accuracy = SearchMatch.A_INACCURATE;
    }

    // Report inaccurate methods
    if (mustResolve) binaryMethods = unresolvedMethods;
    bMethodsLength = binaryMethods == null ? 0 : binaryMethods.length;
    for (int i = 0; i < bMethodsLength; i++) {
      IBinaryMethod method = binaryMethods[i];
      if (method == null) continue; // impossible match or already reported as accurate
      if (matchBinary(pattern, method, info)) {
        char[] name;
        if (method.isConstructor()) {
          name = info.getName();
          int lastSlash = CharOperation.lastIndexOf('/', name);
          if (lastSlash != -1) {
            name = CharOperation.subarray(name, lastSlash + 1, name.length);
          }
        } else {
          name = method.getSelector();
        }
        String selector = new String(name);
        char[] methodSignature = binaryMethodSignatures == null ? null : binaryMethodSignatures[i];
        if (methodSignature == null) {
          methodSignature = method.getGenericSignature();
          if (methodSignature == null) methodSignature = method.getMethodDescriptor();
        }
        String[] parameterTypes =
            CharOperation.toStrings(
                Signature.getParameterTypes(convertClassFileFormat(methodSignature)));
        IMethod methodHandle = binaryType.getMethod(selector, parameterTypes);
        methodHandle =
            new ResolvedBinaryMethod(binaryType, selector, parameterTypes, methodHandle.getKey());
        locator.reportBinaryMemberDeclaration(null, methodHandle, null, info, accuracy);
      }
    }

    // Report inaccurate fields
    if (mustResolve) binaryFields = unresolvedFields;
    bFieldsLength = binaryFields == null ? 0 : binaryFields.length;
    for (int i = 0; i < bFieldsLength; i++) {
      IBinaryField field = binaryFields[i];
      if (field == null) continue; // impossible match or already reported as accurate
      if (matchBinary(pattern, field, info)) {
        String fieldName = new String(field.getName());
        IField fieldHandle = binaryType.getField(fieldName);
        fieldHandle = new ResolvedBinaryField(binaryType, fieldName, fieldHandle.getKey());
        locator.reportBinaryMemberDeclaration(null, fieldHandle, null, info, accuracy);
      }
    }
  }