--- /dev/null	2009-02-04 23:35:14.000000000 -0800
+++ new/src/share/classes/java/dyn/CallSite.java	2009-02-04 23:35:13.000000000 -0800
@@ -0,0 +1,116 @@
+/*
+ * Copyright 2008-2009 Sun Microsystems, Inc.  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.  Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+package java.dyn;
+
+/**
+ * An <code>invokedynamic</code> call site, as reified to the bootstrap method.
+ * Every instance of a call site corresponds to a distinct instance
+ * of the <code>invokedynamic</code> instruction.
+ * Call sites have state, one reference word, called the <code>target</code>,
+ * and typed as a {@link MethodHandle}.  When this state is null (as it is
+ * initially) the call site is in the unlinked state.  Otherwise, it is said
+ * to be linked to its target.
+ * <p>
+ * When an unlinked call site is executed, a bootstrap routine is called
+ * to finish the execution of the call site, and optionally to link
+ * the call site.
+ * <p>
+ * @author John Rose, JSR 292 EG
+ */
+public abstract class CallSite {
+    protected MethodHandle target;
+    protected final Object caller;  // usually a class
+    protected final String name;
+    protected final MethodType type;
+
+    protected CallSite(Object caller, String name, MethodType type) {
+        this.caller = caller;
+        this.name = name;
+        this.type = type;
+    }
+
+    /**
+     * Report the current linkage state of the call site.  (This is mutable.)
+     * The value is null if and only if the call site is currently unlinked.
+     * @return the current linkage state of the call site
+     */
+    public MethodHandle getTarget() {
+        return target;
+    }
+
+    /**
+     * Link or relink the call site, by setting its target method.
+     * @param target the new target, or null if it is to be unlinked
+     * @throws WrongMethodTypeException if the new target is not null
+     *         and has a method type that differs from the call site type
+     */
+    public void setTarget(MethodHandle target) {
+        checkTarget(target);
+        this.target = target;
+    }
+    
+    protected void checkTarget(MethodHandle target) {
+        if (!canSetTarget(target))
+            throw new WrongMethodTypeException(String.valueOf(target));
+    }
+
+    protected boolean canSetTarget(MethodHandle target) {
+        return (target == null || target.type() == type());
+    }
+
+    /**
+     * Report the class containing the call site.
+     * This is immutable static context.
+     * @return class containing the call site
+     */
+    public Class<?> callerClass() {
+        return (Class) caller;
+    }
+
+    /**
+     * Report the method name specified in the {@code invokedynamic} instruction.
+     * This is immutable static context.
+     * @return method name specified by the call site
+     */
+    public String name() {
+        return name;
+    }
+
+    /*
+     * Report the result and parameter types, derived from the invocation descriptor, and resolved
+     * against the calling class's class loader.
+     * This is immutable static context.
+     * @return method type specified by the call site
+     */
+    public MethodType type() {
+        return type;
+    }
+
+    @Override
+    public String toString() {
+        return "CallSite#"+hashCode()+"["+name+type+" => "+target+"]";
+    }
+}