src/share/classes/java/lang/reflect/Executable.java

*** 224,233 ****
--- 224,245 ----
       * represents
       */
      public abstract Class<?>[] getParameterTypes();
  
      /**
+      * Returns the number of formal parameters (including any
+      * synthetic or synthesized parameters) 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.
       *
*** 257,266 ****
--- 269,332 ----
          else
              return getParameterTypes();
      }
  
      /**
+      * 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.
+      *
+      * @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 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
+             tmp = getParameters0();
+ 
+             // If we get back nothing, then synthesize parameters
+             if (tmp == null)
+                 tmp = synthesizeAllParams();
+ 
+             parameters = tmp;
+         }
+ 
+         return tmp;
+     }
+ 
+     private transient volatile Parameter[] parameters;
+ 
+     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.
*** 401,406 ****
--- 467,473 ----
                  getConstantPool(getDeclaringClass()),
                  getDeclaringClass());
          }
          return declaredAnnotations;
      }
+ 
  }