--- a/jdk/src/java.base/share/classes/java/lang/invoke/MethodHandle.java	Thu Jan 29 10:27:30 2015 -0800
+++ b/jdk/src/java.base/share/classes/java/lang/invoke/MethodHandle.java	Thu Jan 29 10:27:30 2015 -0800
@@ -434,6 +434,8 @@
     // form is not private so that invokers can easily fetch it
     /*private*/ MethodHandle asTypeCache;
     // asTypeCache is not private so that invokers can easily fetch it
+    /*non-public*/ byte customizationCount;
+    // customizationCount should be accessible from invokers
 
     /**
      * Reports the type of this method handle.
@@ -454,9 +456,9 @@
         type.getClass();  // explicit NPE
         form.getClass();  // explicit NPE
         this.type = type;
-        this.form = form;
+        this.form = form.uncustomize();
 
-        form.prepare();  // TO DO:  Try to delay this step until just before invocation.
+        this.form.prepare();  // TO DO:  Try to delay this step until just before invocation.
     }
 
     /**
@@ -1425,12 +1427,24 @@
      */
     /*non-public*/
     void updateForm(LambdaForm newForm) {
+        assert(newForm.customized == null || newForm.customized == this);
         if (form == newForm)  return;
         newForm.prepare();  // as in MethodHandle.<init>
         UNSAFE.putObject(this, FORM_OFFSET, newForm);
         UNSAFE.fullFence();
     }
 
+    /** Craft a LambdaForm customized for this particular MethodHandle */
+    /*non-public*/
+    void customize() {
+        if (form.customized == null) {
+            LambdaForm newForm = form.customize(this);
+            updateForm(newForm);
+        } else {
+            assert(form.customized == this);
+        }
+    }
+
     private static final long FORM_OFFSET;
     static {
         try {