diff -r 0c9d42e88feb -r 1990493b64db langtools/src/share/classes/com/sun/tools/javac/api/ClientCodeWrapper.java
--- a/langtools/src/share/classes/com/sun/tools/javac/api/ClientCodeWrapper.java	Tue Feb 28 10:25:53 2012 -0800
+++ b/langtools/src/share/classes/com/sun/tools/javac/api/ClientCodeWrapper.java	Tue Feb 28 10:33:49 2012 -0800
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2011, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2011, 2012, 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
@@ -31,8 +31,13 @@
 import java.io.OutputStream;
 import java.io.Reader;
 import java.io.Writer;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
 import java.net.URI;
 import java.util.ArrayList;
+import java.util.Collection;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.Iterator;
@@ -41,25 +46,21 @@
 import java.util.Map;
 import java.util.Set;
 
+import javax.lang.model.element.Modifier;
 import javax.lang.model.element.NestingKind;
 import javax.tools.Diagnostic;
+import javax.tools.DiagnosticListener;
 import javax.tools.FileObject;
 import javax.tools.JavaFileManager;
 import javax.tools.JavaFileManager.Location;
 import javax.tools.JavaFileObject;
+import javax.tools.JavaFileObject.Kind;
 
 import com.sun.source.util.TaskEvent;
 import com.sun.source.util.TaskListener;
 import com.sun.tools.javac.util.ClientCodeException;
 import com.sun.tools.javac.util.Context;
 import com.sun.tools.javac.util.JCDiagnostic;
-import java.lang.annotation.ElementType;
-import java.lang.annotation.Retention;
-import java.lang.annotation.RetentionPolicy;
-import java.lang.annotation.Target;
-import javax.lang.model.element.Modifier;
-import javax.tools.DiagnosticListener;
-import javax.tools.JavaFileObject.Kind;
 
 /**
  *  Wrap objects to enable unchecked exceptions to be caught and handled.
@@ -160,6 +161,20 @@
         return new WrappedTaskListener(tl);
     }
 
+    TaskListener unwrap(TaskListener l) {
+        if (l instanceof WrappedTaskListener)
+            return ((WrappedTaskListener) l).clientTaskListener;
+        else
+            return l;
+    }
+
+    Collection<TaskListener> unwrap(Collection<? extends TaskListener> listeners) {
+        Collection<TaskListener> c = new ArrayList<TaskListener>(listeners.size());
+        for (TaskListener l: listeners)
+            c.add(unwrap(l));
+        return c;
+    }
+
     @SuppressWarnings("unchecked")
     private <T> Diagnostic<T> unwrap(final Diagnostic<T> diagnostic) {
         if (diagnostic instanceof JCDiagnostic) {
@@ -181,6 +196,10 @@
         return trusted;
     }
 
+    private String wrappedToString(Class<?> wrapperClass, Object wrapped) {
+        return wrapperClass.getSimpleName() + "[" + wrapped + "]";
+    }
+
     // <editor-fold defaultstate="collapsed" desc="Wrapper classes">
 
     // FIXME: all these classes should be converted to use multi-catch when
@@ -361,6 +380,11 @@
                 throw new ClientCodeException(e);
             }
         }
+
+        @Override
+        public String toString() {
+            return wrappedToString(getClass(), clientJavaFileManager);
+        }
     }
 
     protected class WrappedFileObject implements FileObject {
@@ -486,6 +510,11 @@
                 throw new ClientCodeException(e);
             }
         }
+
+        @Override
+        public String toString() {
+            return wrappedToString(getClass(), clientFileObject);
+        }
     }
 
     protected class WrappedJavaFileObject extends WrappedFileObject implements JavaFileObject {
@@ -544,6 +573,11 @@
                 throw new ClientCodeException(e);
             }
         }
+
+        @Override
+        public String toString() {
+            return wrappedToString(getClass(), clientFileObject);
+        }
     }
 
     protected class WrappedDiagnosticListener<T /*super JavaFileObject*/> implements DiagnosticListener<T> {
@@ -565,6 +599,11 @@
                 throw new ClientCodeException(e);
             }
         }
+
+        @Override
+        public String toString() {
+            return wrappedToString(getClass(), clientDiagnosticListener);
+        }
     }
 
     public class DiagnosticSourceUnwrapper implements Diagnostic<JavaFileObject> {
@@ -610,6 +649,7 @@
             return d.getMessage(locale);
         }
 
+        @Override
         public String toString() {
             return d.toString();
         }
@@ -647,6 +687,11 @@
                 throw new ClientCodeException(e);
             }
         }
+
+        @Override
+        public String toString() {
+            return wrappedToString(getClass(), clientTaskListener);
+        }
     }
 
     // </editor-fold>