8005075: Pool.Method, and Pool.Variable redundant Symbol field should be removed

Reviewed-by: jjg

src/share/classes/com/sun/tools/javac/code/Symbol.java

@@ -496,9 +496,9 @@ public abstract class Symbol implements Element {
         return l.toList();
     }
 
-    public static class DelegatedSymbol extends Symbol {
-        protected Symbol other;
-        public DelegatedSymbol(Symbol other) {
+    public static class DelegatedSymbol<T extends Symbol> extends Symbol {
+        protected T other;
+        public DelegatedSymbol(T other) {
             super(other.kind, other.flags_field, other.name, other.type, other.owner);
             this.other = other;
         }
@@ -532,6 +532,10 @@ public abstract class Symbol implements Element {
         public <R, P> R accept(Symbol.Visitor<R, P> v, P p) {
             return v.visitSymbol(other, p);
         }
+
+        public T getUnderlyingSymbol() {
+            return other;
+        }
     }
 
     /** A class for type symbols. Type variables are represented by instances

src/share/classes/com/sun/tools/javac/jvm/ClassWriter.java

@@ -482,10 +482,8 @@ public class ClassWriter extends ClassFile {
         while (i < pool.pp) {
             Object value = pool.pool[i];
             Assert.checkNonNull(value);
-            if (value instanceof Method)
-                value = ((Method)value).m;
-            else if (value instanceof Variable)
-                value = ((Variable)value).v;
+            if (value instanceof Method || value instanceof Variable)
+                value = ((DelegatedSymbol)value).getUnderlyingSymbol();
 
             if (value instanceof MethodSymbol) {
                 MethodSymbol m = (MethodSymbol)value;

src/share/classes/com/sun/tools/javac/jvm/Pool.java

 /*
- * Copyright (c) 1999, 2012, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1999, 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
@@ -140,23 +140,23 @@ public class Pool {
         return n == null ? -1 : n.intValue();
     }
 
-    static class Method extends DelegatedSymbol {
-        MethodSymbol m;
+    static class Method extends DelegatedSymbol<MethodSymbol> {
         UniqueType uniqueType;
         Method(MethodSymbol m, Types types) {
             super(m);
-            this.m = m;
             this.uniqueType = new UniqueType(m.type, types);
         }
-        public boolean equals(Object other) {
-            if (!(other instanceof Method)) return false;
-            MethodSymbol o = ((Method)other).m;
+        public boolean equals(Object any) {
+            if (!(any instanceof Method)) return false;
+            MethodSymbol o = ((Method)any).other;
+            MethodSymbol m = this.other;
             return
                 o.name == m.name &&
                 o.owner == m.owner &&
-                ((Method)other).uniqueType.equals(uniqueType);
+                ((Method)any).uniqueType.equals(uniqueType);
         }
         public int hashCode() {
+            MethodSymbol m = this.other;
             return
                 m.name.hashCode() * 33 +
                 m.owner.hashCode() * 9 +
@@ -173,21 +173,21 @@ public class Pool {
         }
 
         @Override
-        public boolean equals(Object other) {
-            if (!super.equals(other)) return false;
-            if (!(other instanceof DynamicMethod)) return false;
-            DynamicMethodSymbol dm1 = (DynamicMethodSymbol)m;
-            DynamicMethodSymbol dm2 = (DynamicMethodSymbol)((DynamicMethod)other).m;
+        public boolean equals(Object any) {
+            if (!super.equals(any)) return false;
+            if (!(any instanceof DynamicMethod)) return false;
+            DynamicMethodSymbol dm1 = (DynamicMethodSymbol)other;
+            DynamicMethodSymbol dm2 = (DynamicMethodSymbol)((DynamicMethod)any).other;
             return dm1.bsm == dm2.bsm &&
                         dm1.bsmKind == dm2.bsmKind &&
                         Arrays.equals(uniqueStaticArgs,
-                            ((DynamicMethod)other).uniqueStaticArgs);
+                            ((DynamicMethod)any).uniqueStaticArgs);
         }
 
         @Override
         public int hashCode() {
             int hash = super.hashCode();
-            DynamicMethodSymbol dm = (DynamicMethodSymbol)m;
+            DynamicMethodSymbol dm = (DynamicMethodSymbol)other;
             hash += dm.bsmKind * 7 +
                     dm.bsm.hashCode() * 11;
             for (int i = 0; i < dm.staticArgs.length; i++) {
@@ -209,23 +209,23 @@ public class Pool {
         }
     }
 
-    static class Variable extends DelegatedSymbol {
-        VarSymbol v;
+    static class Variable extends DelegatedSymbol<VarSymbol> {
         UniqueType uniqueType;
         Variable(VarSymbol v, Types types) {
             super(v);
-            this.v = v;
             this.uniqueType = new UniqueType(v.type, types);
         }
-        public boolean equals(Object other) {
-            if (!(other instanceof Variable)) return false;
-            VarSymbol o = ((Variable)other).v;
+        public boolean equals(Object any) {
+            if (!(any instanceof Variable)) return false;
+            VarSymbol o = ((Variable)any).other;
+            VarSymbol v = other;
             return
                 o.name == v.name &&
                 o.owner == v.owner &&
-                ((Variable)other).uniqueType.equals(uniqueType);
+                ((Variable)any).uniqueType.equals(uniqueType);
         }
         public int hashCode() {
+            VarSymbol v = other;
             return
                 v.name.hashCode() * 33 +
                 v.owner.hashCode() * 9 +