AnnotationFactory.java 文件源码

/**
   * Processes a method invocation request to this annotation instance.
   * Recognizes the methods declared in the 
   * {@link java.lang.annotation.Annotation java.lang.annotation.Annotation}
   * interface, and member-defining methods of the implemented annotation type.
   * @throws IllegalArgumentException If the specified method is none of the above
   * @return the invocation result 
   */
  public Object invoke(Object proxy, Method method, Object[] args) throws Throwable
  {
      String name = method.getName();
      Class[] params = method.getParameterTypes();
      if (params.length == 0) {
          if ("annotationType".equals(name)) {
              return klazz;
          } else if ("toString".equals(name)) {
              return toString();
          } else if ("hashCode".equals(name)) {
              return hashCode();
          }

          // this must be element value request
          AnnotationMember element = null;
          for (AnnotationMember el : elements) {
              if (name.equals(el.name)) {
                  element = el;
                  break;
              }                
          }
          if (element == null || !method.equals(element.definingMethod)) {
              throw new IllegalArgumentException(method.toString());
          } else {
              Object value = element.validateValue();
              if (value == null) {
                  throw new IncompleteAnnotationException(klazz, name);
              }
              return value;
          }
} else if (params.length == 1 && params[0] == Object.class && "equals".equals(name)){
    return Boolean.valueOf(equals(args[0]));
      }
      throw new IllegalArgumentException(
              "Invalid method for annotation type: " + method);
  }