8210721: Replace legacy serial exception field with Throwable::cause
authormchung
Mon, 17 Sep 2018 15:22:46 -0700
changeset 51772 5432cebf6627
parent 51771 1f805481d8de
child 51773 720fd6544b03
8210721: Replace legacy serial exception field with Throwable::cause Reviewed-by: dfuchs, lancea
src/java.base/share/classes/java/lang/ClassNotFoundException.java
src/java.base/share/classes/java/lang/ExceptionInInitializerError.java
src/java.base/share/classes/java/lang/System.java
src/java.base/share/classes/java/lang/Throwable.java
src/java.base/share/classes/java/lang/reflect/InvocationTargetException.java
src/java.base/share/classes/java/lang/reflect/UndeclaredThrowableException.java
src/java.base/share/classes/java/security/PrivilegedActionException.java
src/java.base/share/classes/jdk/internal/misc/JavaLangAccess.java
test/jdk/java/lang/Throwable/LegacyChainedExceptionSerialization.java
--- a/src/java.base/share/classes/java/lang/ClassNotFoundException.java	Mon Sep 17 14:04:46 2018 -0700
+++ b/src/java.base/share/classes/java/lang/ClassNotFoundException.java	Mon Sep 17 15:22:46 2018 -0700
@@ -25,6 +25,11 @@
 
 package java.lang;
 
+import java.io.IOException;
+import java.io.ObjectInputStream;
+import java.io.ObjectOutputStream;
+import java.io.ObjectStreamField;
+
 /**
  * Thrown when an application tries to load in a class through its
  * string name using:
@@ -57,15 +62,6 @@
      private static final long serialVersionUID = 9176873029745254542L;
 
     /**
-     * This field holds the exception ex if the
-     * ClassNotFoundException(String s, Throwable ex) constructor was
-     * used to instantiate the object
-     * @serial
-     * @since 1.2
-     */
-    private Throwable ex;
-
-    /**
      * Constructs a <code>ClassNotFoundException</code> with no detail message.
      */
     public ClassNotFoundException() {
@@ -92,8 +88,7 @@
      * @since 1.2
      */
     public ClassNotFoundException(String s, Throwable ex) {
-        super(s, null);  //  Disallow initCause
-        this.ex = ex;
+        super(s, ex);  //  Disallow initCause
     }
 
     /**
@@ -108,18 +103,42 @@
      * @since 1.2
      */
     public Throwable getException() {
-        return ex;
+        return super.getCause();
     }
 
     /**
-     * Returns the cause of this exception (the exception that was raised
-     * if an error occurred while attempting to load the class; otherwise
-     * {@code null}).
+     * Serializable fields for ClassNotFoundException.
+     *
+     * @serialField ex Throwable
+     */
+    private static final ObjectStreamField[] serialPersistentFields = {
+        new ObjectStreamField("ex", Throwable.class)
+    };
+
+    /*
+     * Reconstitutes the ClassNotFoundException instance from a stream
+     * and initialize the cause properly when deserializing from an older
+     * version.
      *
-     * @return  the cause of this exception.
-     * @since   1.4
+     * The getException and getCause method returns the private "ex" field
+     * in the older implementation and ClassNotFoundException::cause
+     * was set to null.
      */
-    public Throwable getCause() {
-        return ex;
+    private void readObject(ObjectInputStream s) throws IOException, ClassNotFoundException {
+        ObjectInputStream.GetField fields = s.readFields();
+        Throwable exception = (Throwable) fields.get("ex", null);
+        if (exception != null) {
+            setCause(exception);
+        }
+    }
+
+    /*
+     * To maintain compatibility with older implementation, write a serial
+     * "ex" field with the cause as the value.
+     */
+    private void writeObject(ObjectOutputStream out) throws IOException {
+        ObjectOutputStream.PutField fields = out.putFields();
+        fields.put("ex", super.getCause());
+        out.writeFields();
     }
 }
--- a/src/java.base/share/classes/java/lang/ExceptionInInitializerError.java	Mon Sep 17 14:04:46 2018 -0700
+++ b/src/java.base/share/classes/java/lang/ExceptionInInitializerError.java	Mon Sep 17 15:22:46 2018 -0700
@@ -25,6 +25,11 @@
 
 package java.lang;
 
+import java.io.IOException;
+import java.io.ObjectInputStream;
+import java.io.ObjectOutputStream;
+import java.io.ObjectStreamField;
+
 /**
  * Signals that an unexpected exception has occurred in a static initializer.
  * An <code>ExceptionInInitializerError</code> is thrown to indicate that an
@@ -48,23 +53,13 @@
     private static final long serialVersionUID = 1521711792217232256L;
 
     /**
-     * This field holds the exception if the
-     * ExceptionInInitializerError(Throwable thrown) constructor was
-     * used to instantiate the object
-     *
-     * @serial
-     *
-     */
-    private Throwable exception;
-
-    /**
      * Constructs an <code>ExceptionInInitializerError</code> with
      * <code>null</code> as its detail message string and with no saved
      * throwable object.
      * A detail message is a String that describes this particular exception.
      */
     public ExceptionInInitializerError() {
-        initCause(null);  // Disallow subsequent initCause
+        initCause(null); // Disallow subsequent initCause
     }
 
     /**
@@ -76,23 +71,20 @@
      * @param thrown The exception thrown
      */
     public ExceptionInInitializerError(Throwable thrown) {
-        initCause(null);  // Disallow subsequent initCause
-        this.exception = thrown;
+        super(null, thrown); // Disallow subsequent initCause
     }
 
     /**
-     * Constructs an ExceptionInInitializerError with the specified detail
+     * Constructs an {@code ExceptionInInitializerError} with the specified detail
      * message string.  A detail message is a String that describes this
      * particular exception. The detail message string is saved for later
      * retrieval by the {@link Throwable#getMessage()} method. There is no
      * saved throwable object.
      *
-     *
      * @param s the detail message
      */
     public ExceptionInInitializerError(String s) {
-        super(s);
-        initCause(null);  // Disallow subsequent initCause
+        super(s, null);  // Disallow subsequent initCause
     }
 
     /**
@@ -109,18 +101,43 @@
      *         throwable object.
      */
     public Throwable getException() {
-        return exception;
+        return super.getCause();
     }
 
     /**
-     * Returns the cause of this error (the exception that occurred
-     * during a static initialization that caused this error to be created).
+     * Serializable fields for ExceptionInInitializerError.
+     *
+     * @serialField exception Throwable
+     */
+    private static final ObjectStreamField[] serialPersistentFields = {
+        new ObjectStreamField("exception", Throwable.class)
+    };
+
+    /*
+     * Reconstitutes the ExceptionInInitializerError instance from a stream
+     * and initialize the cause properly when deserializing from an older
+     * version.
      *
-     * @return  the cause of this error or <code>null</code> if the
-     *          cause is nonexistent or unknown.
-     * @since   1.4
+     * The getException and getCause method returns the private "exception"
+     * field in the older implementation and ExceptionInInitializerError::cause
+     * was set to null.
      */
-    public Throwable getCause() {
-        return exception;
+    private void readObject(ObjectInputStream s) throws IOException, ClassNotFoundException {
+        ObjectInputStream.GetField fields = s.readFields();
+        Throwable exception = (Throwable) fields.get("exception", null);
+        if (exception != null) {
+            setCause(exception);
+        }
     }
+
+    /*
+     * To maintain compatibility with older implementation, write a serial
+     * "exception" field with the cause as the value.
+     */
+    private void writeObject(ObjectOutputStream out) throws IOException {
+        ObjectOutputStream.PutField fields = out.putFields();
+        fields.put("exception", super.getCause());
+        out.writeFields();
+    }
+
 }
--- a/src/java.base/share/classes/java/lang/System.java	Mon Sep 17 14:04:46 2018 -0700
+++ b/src/java.base/share/classes/java/lang/System.java	Mon Sep 17 15:22:46 2018 -0700
@@ -2201,6 +2201,9 @@
                 return StringCoding.getBytesUTF8NoRepl(s);
             }
 
+            public void setCause(Throwable t, Throwable cause) {
+                t.setCause(cause);
+            }
         });
     }
 }
--- a/src/java.base/share/classes/java/lang/Throwable.java	Mon Sep 17 14:04:46 2018 -0700
+++ b/src/java.base/share/classes/java/lang/Throwable.java	Mon Sep 17 15:22:46 2018 -0700
@@ -466,6 +466,16 @@
         return this;
     }
 
+    /*
+     * This is called by readObject of a few exceptions such as
+     * ClassNotFoundException and ExceptionInInitializerError to deserialize
+     * a stream output from an older runtime version where the cause may
+     * have set to null.
+     */
+    final void setCause(Throwable t) {
+        this.cause = t;
+    }
+
     /**
      * Returns a short description of this throwable.
      * The result is the concatenation of:
--- a/src/java.base/share/classes/java/lang/reflect/InvocationTargetException.java	Mon Sep 17 14:04:46 2018 -0700
+++ b/src/java.base/share/classes/java/lang/reflect/InvocationTargetException.java	Mon Sep 17 15:22:46 2018 -0700
@@ -25,6 +25,12 @@
 
 package java.lang.reflect;
 
+import java.io.IOException;
+import java.io.ObjectInputStream;
+import java.io.ObjectOutputStream;
+import java.io.ObjectStreamField;
+import jdk.internal.misc.SharedSecrets;
+
 /**
  * InvocationTargetException is a checked exception that wraps
  * an exception thrown by an invoked method or constructor.
@@ -46,16 +52,6 @@
      */
     private static final long serialVersionUID = 4085088731926701167L;
 
-     /**
-     * This field holds the target if the
-     * InvocationTargetException(Throwable target) constructor was
-     * used to instantiate the object
-     *
-     * @serial
-     *
-     */
-    private Throwable target;
-
     /**
      * Constructs an {@code InvocationTargetException} with
      * {@code null} as the target exception.
@@ -70,8 +66,7 @@
      * @param target the target exception
      */
     public InvocationTargetException(Throwable target) {
-        super((Throwable)null);  // Disallow initCause
-        this.target = target;
+        super(null, target);  // Disallow initCause
     }
 
     /**
@@ -82,8 +77,7 @@
      * @param s      the detail message
      */
     public InvocationTargetException(Throwable target, String s) {
-        super(s, null);  // Disallow initCause
-        this.target = target;
+        super(s, target);  // Disallow initCause
     }
 
     /**
@@ -96,17 +90,42 @@
      * @return the thrown target exception (cause of this exception).
      */
     public Throwable getTargetException() {
-        return target;
+        return super.getCause();
     }
 
     /**
-     * Returns the cause of this exception (the thrown target exception,
-     * which may be {@code null}).
+     * Serializable fields for UndeclaredThrowableException.
+     *
+     * @serialField target Throwable
+     */
+    private static final ObjectStreamField[] serialPersistentFields = {
+        new ObjectStreamField("target", Throwable.class)
+    };
+
+    /*
+     * Reconstitutes the InvocationTargetException instance from a stream
+     * and initialize the cause properly when deserializing from an older
+     * version.
      *
-     * @return  the cause of this exception.
-     * @since   1.4
+     * The getException and getCause method returns the private "target" field
+     * in the older implementation and InvocationTargetException::cause
+     * was set to null.
      */
-    public Throwable getCause() {
-        return target;
+    private void readObject(ObjectInputStream s) throws IOException, ClassNotFoundException {
+        ObjectInputStream.GetField fields = s.readFields();
+        Throwable exception = (Throwable) fields.get("target", null);
+        if (exception != null) {
+            SharedSecrets.getJavaLangAccess().setCause(this, exception);
+        }
+    }
+
+    /*
+     * To maintain compatibility with older implementation, write a serial
+     * "target" field with the cause as the value.
+     */
+    private void writeObject(ObjectOutputStream out) throws IOException {
+        ObjectOutputStream.PutField fields = out.putFields();
+        fields.put("target", super.getCause());
+        out.writeFields();
     }
 }
--- a/src/java.base/share/classes/java/lang/reflect/UndeclaredThrowableException.java	Mon Sep 17 14:04:46 2018 -0700
+++ b/src/java.base/share/classes/java/lang/reflect/UndeclaredThrowableException.java	Mon Sep 17 15:22:46 2018 -0700
@@ -25,6 +25,12 @@
 
 package java.lang.reflect;
 
+import java.io.IOException;
+import java.io.ObjectInputStream;
+import java.io.ObjectOutputStream;
+import java.io.ObjectStreamField;
+import jdk.internal.misc.SharedSecrets;
+
 /**
  * Thrown by a method invocation on a proxy instance if its invocation
  * handler's {@link InvocationHandler#invoke invoke} method throws a
@@ -59,12 +65,6 @@
     static final long serialVersionUID = 330127114055056639L;
 
     /**
-     * the undeclared checked exception that was thrown
-     * @serial
-     */
-    private Throwable undeclaredThrowable;
-
-    /**
      * Constructs an {@code UndeclaredThrowableException} with the
      * specified {@code Throwable}.
      *
@@ -72,8 +72,7 @@
      *          that was thrown
      */
     public UndeclaredThrowableException(Throwable undeclaredThrowable) {
-        super((Throwable) null);  // Disallow initCause
-        this.undeclaredThrowable = undeclaredThrowable;
+        super(null, undeclaredThrowable);  // Disallow initCause
     }
 
     /**
@@ -87,8 +86,7 @@
     public UndeclaredThrowableException(Throwable undeclaredThrowable,
                                         String s)
     {
-        super(s, null);  // Disallow initCause
-        this.undeclaredThrowable = undeclaredThrowable;
+        super(s, undeclaredThrowable);  // Disallow initCause
     }
 
     /**
@@ -102,18 +100,38 @@
      * @return the undeclared checked exception that was thrown
      */
     public Throwable getUndeclaredThrowable() {
-        return undeclaredThrowable;
+        return super.getCause();
     }
 
     /**
-     * Returns the cause of this exception (the {@code Throwable}
-     * instance wrapped in this {@code UndeclaredThrowableException},
-     * which may be {@code null}).
+     * Serializable fields for UndeclaredThrowableException.
      *
-     * @return  the cause of this exception.
-     * @since   1.4
+     * @serialField undeclaredThrowable Throwable
+     */
+    private static final ObjectStreamField[] serialPersistentFields = {
+        new ObjectStreamField("undeclaredThrowable", Throwable.class)
+    };
+
+    /*
+     * Reconstitutes the UndeclaredThrowableException instance from a stream
+     * and initialize the cause properly when deserializing from an older
+     * version.
      */
-    public Throwable getCause() {
-        return undeclaredThrowable;
+    private void readObject(ObjectInputStream s) throws IOException, ClassNotFoundException {
+        ObjectInputStream.GetField fields = s.readFields();
+        Throwable exception = (Throwable) fields.get("undeclaredThrowable", null);
+        if (exception != null) {
+            SharedSecrets.getJavaLangAccess().setCause(this, exception);
+        }
+    }
+
+    /*
+     * To maintain compatibility with older implementation, write a serial
+     * "ex" field with the cause as the value.
+     */
+    private void writeObject(ObjectOutputStream out) throws IOException {
+        ObjectOutputStream.PutField fields = out.putFields();
+        fields.put("undeclaredThrowable", super.getCause());
+        out.writeFields();
     }
 }
--- a/src/java.base/share/classes/java/security/PrivilegedActionException.java	Mon Sep 17 14:04:46 2018 -0700
+++ b/src/java.base/share/classes/java/security/PrivilegedActionException.java	Mon Sep 17 15:22:46 2018 -0700
@@ -25,6 +25,12 @@
 
 package java.security;
 
+import java.io.IOException;
+import java.io.ObjectInputStream;
+import java.io.ObjectOutputStream;
+import java.io.ObjectStreamField;
+import jdk.internal.misc.SharedSecrets;
+
 /**
  * This exception is thrown by
  * {@code doPrivileged(PrivilegedExceptionAction)} and
@@ -53,19 +59,13 @@
     private static final long serialVersionUID = 4724086851538908602L;
 
     /**
-     * @serial
-     */
-    private Exception exception;
-
-    /**
      * Constructs a new PrivilegedActionException &quot;wrapping&quot;
      * the specific Exception.
      *
      * @param exception The exception thrown
      */
     public PrivilegedActionException(Exception exception) {
-        super((Throwable)null);  // Disallow initCause
-        this.exception = exception;
+        super(null, exception);  // Disallow initCause
     }
 
     /**
@@ -84,23 +84,49 @@
      *                                            AccessControlContext)
      */
     public Exception getException() {
-        return exception;
-    }
-
-    /**
-     * Returns the cause of this exception (the exception thrown by
-     * the privileged computation that resulted in this
-     * {@code PrivilegedActionException}).
-     *
-     * @return  the cause of this exception.
-     * @since   1.4
-     */
-    public Throwable getCause() {
-        return exception;
+        return (Exception)super.getCause();
     }
 
     public String toString() {
         String s = getClass().getName();
-        return (exception != null) ? (s + ": " + exception.toString()) : s;
+        Throwable cause = super.getCause();
+        return (cause != null) ? (s + ": " + cause.toString()) : s;
+    }
+
+
+    /**
+     * Serializable fields for UndeclaredThrowableException.
+     *
+     * @serialField undeclaredThrowable Throwable
+     */
+    private static final ObjectStreamField[] serialPersistentFields = {
+        new ObjectStreamField("exception", Exception.class)
+    };
+
+    /*
+     * Reconstitutes the PrivilegedActionException instance from a stream
+     * and initialize the cause properly when deserializing from an older
+     * version.
+     *
+     * The getException and getCause method returns the private "exception"
+     * field in the older implementation and PrivilegedActionException::cause
+     * was set to null.
+     */
+    private void readObject(ObjectInputStream s) throws IOException, ClassNotFoundException {
+        ObjectInputStream.GetField fields = s.readFields();
+        Exception exception = (Exception) fields.get("exception", null);
+        if (exception != null) {
+            SharedSecrets.getJavaLangAccess().setCause(this, exception);
+        }
+    }
+
+    /*
+     * To maintain compatibility with older implementation, write a serial
+     * "exception" field with the cause as the value.
+     */
+    private void writeObject(ObjectOutputStream out) throws IOException {
+        ObjectOutputStream.PutField fields = out.putFields();
+        fields.put("exception", super.getCause());
+        out.writeFields();
     }
 }
--- a/src/java.base/share/classes/jdk/internal/misc/JavaLangAccess.java	Mon Sep 17 14:04:46 2018 -0700
+++ b/src/java.base/share/classes/jdk/internal/misc/JavaLangAccess.java	Mon Sep 17 15:22:46 2018 -0700
@@ -305,4 +305,10 @@
      * @throws IllegalArgumentException for malformed surrogates
      */
     byte[] getBytesUTF8NoRepl(String s);
+
+    /**
+     * Set the cause of Throwable
+     * @param cause set t's cause to new value
+     */
+    void setCause(Throwable t, Throwable cause);
 }
--- a/test/jdk/java/lang/Throwable/LegacyChainedExceptionSerialization.java	Mon Sep 17 14:04:46 2018 -0700
+++ b/test/jdk/java/lang/Throwable/LegacyChainedExceptionSerialization.java	Mon Sep 17 15:22:46 2018 -0700
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000, 2012, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2000, 2018, 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
@@ -22,10 +22,15 @@
  */
 
 import java.io.*;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.UndeclaredThrowableException;
+import java.security.PrivilegedActionException;
+import java.util.Base64;
+import java.util.Map;
 
 /**
  * @test
- * @bug     4385429 8004928
+ * @bug     4385429 8004928 8210721
  * @summary Certain legacy chained exceptions throw IllegalArgumentException
  *          upon deserialization if "causative exception" is null.
  * @author  Josh Bloch
@@ -33,18 +38,31 @@
 public class LegacyChainedExceptionSerialization {
     private static Throwable[] broken = {
         new ClassNotFoundException(),
+        new ClassNotFoundException("bar", new IOException("reading class file")),
         new ExceptionInInitializerError(),
+        new ExceptionInInitializerError(new NullPointerException("foo")),
         new java.lang.reflect.UndeclaredThrowableException(null),
+        new java.lang.reflect.UndeclaredThrowableException(new IllegalArgumentException("foo")),
         new java.lang.reflect.InvocationTargetException(null),
-        new java.security.PrivilegedActionException(null)
+        new java.lang.reflect.InvocationTargetException(new Error("goo")),
+        new java.security.PrivilegedActionException(null),
+        new java.security.PrivilegedActionException(new IOException("foo")),
     };
 
+
     public static void main(String[] args) throws Exception {
         for (int i=0; i<broken.length; i++)
             test(broken[i]);
+
+        for (Map.Entry<String, Throwable> e : SERIALIZED_DATA.entrySet()) {
+            Throwable t = deserialize(e.getKey());
+            verify(t, e.getValue());
+        }
+
+        testOverriddenGetCause();
     }
 
-    private static void test(Throwable e) throws Exception {
+    private static Throwable test(Throwable e) throws Exception {
         ByteArrayOutputStream bout = new ByteArrayOutputStream();
         ObjectOutputStream out = new ObjectOutputStream(bout);
         out.writeObject(e);
@@ -54,5 +72,247 @@
             new ByteArrayInputStream(bout.toByteArray());
         ObjectInputStream in = new ObjectInputStream(bin);
         Throwable clone = (Throwable) in.readObject();
+        return clone;
     }
+
+    private static void testOverriddenGetCause() throws Exception {
+        SubClass sc = new SubClass(new NullPointerException());
+        SubClass clone = (SubClass)test(sc);
+        Throwable cause = clone.getException();
+        if (!(cause instanceof NullPointerException) || cause.getMessage() != null) {
+            throw new RuntimeException("unexpected cause: " + cause);
+        }
+
+    }
+
+    private static Throwable deserialize(String ser) throws Exception {
+        Base64.Decoder decoder = Base64.getDecoder();
+        try (ByteArrayInputStream bin = new ByteArrayInputStream(decoder.decode(ser));
+             ObjectInputStream ois = new ObjectInputStream(bin)) {
+            return (Throwable)ois.readObject();
+        }
+    }
+
+    /*
+     * Verify the deserialization of the serialized data from an old version.
+     * See SERIALIZED_DATA.
+     */
+    private static void verify(Throwable t, Throwable expected) {
+        String msg = expected.getMessage();
+        Throwable cause = expected.getCause();
+        if (t.getMessage() != msg && msg != null && !msg.equals(t.getMessage())) {
+            throw new RuntimeException("unexpected message: " + t.getMessage()
+                    + " expected: " + msg);
+        }
+        Throwable e = t.getCause();
+        if (e.getClass() != cause.getClass()) {
+            throw new RuntimeException("unexpected cause: " + t.getCause());
+        }
+        String causedBy = cause.getMessage();
+        if (e.getMessage() != causedBy) {
+            if (e.getMessage() == null || causedBy == null || !causedBy.equals(e.getMessage())) {
+                throw new RuntimeException("unexpected message: " + t.getMessage()
+                    + " expected: " + causedBy);
+            }
+        }
+        Throwable exception = null;
+        if (t instanceof ExceptionInInitializerError) {
+            exception = ((ExceptionInInitializerError)t).getException();
+        } else if (t instanceof ClassNotFoundException) {
+            exception = ((ClassNotFoundException)t).getException();
+        } else if (t instanceof InvocationTargetException) {
+            exception = ((InvocationTargetException) t).getTargetException();
+        } else if (t instanceof UndeclaredThrowableException) {
+            exception = ((UndeclaredThrowableException) t).getUndeclaredThrowable();
+        } else if (t instanceof PrivilegedActionException) {
+            exception = ((PrivilegedActionException) t).getException();
+        } else {
+            // skip the cause == exception check below
+            e = null;
+        }
+        if (e != exception) {
+            throw new RuntimeException("unexpected exception: " + exception);
+        }
+    }
+
+    static class SubClass extends ExceptionInInitializerError {
+        public SubClass(Throwable t) {
+            super(t);
+        }
+        @Override
+        public Throwable getCause() {
+            return new Throwable("always new");
+        }
+    }
+
+    /*
+     * The following strings are base64-encoded serialized data generated
+     * by running the jdk10SerializeThrowable method with JDK 10 runtime.
+     *
+     *   private static void jdk10SerializeThrowable(Throwable e) throws Exception {
+     *       Base64.Encoder encoder = Base64.getEncoder();
+     *       try (ByteArrayOutputStream os = new ByteArrayOutputStream();
+     *            ObjectOutputStream out = new ObjectOutputStream(os)) {
+     *           out.writeObject(e);
+     *           out.flush();
+     *           String s = encoder.encodeToString(os.toByteArray());
+     *           for (int i=0; i < s.length();) {
+     *               int end = Math.min(i+60, s.length());
+     *               CharSequence seq = s.subSequence(i, end);
+     *               System.out.format("\"%s\" +%n", seq);
+     *               i = end;
+     *           }
+     *       }
+     *   }
+     */
+
+    private static final String EIIE_OLD_VERSION =
+        "rO0ABXNyACVqYXZhLmxhbmcuRXhjZXB0aW9uSW5Jbml0aWFsaXplckVycm9y" +
+        "FR400Amhk4ACAAFMAAlleGNlcHRpb250ABVMamF2YS9sYW5nL1Rocm93YWJs" +
+        "ZTt4cgAWamF2YS5sYW5nLkxpbmthZ2VFcnJvcjGtS1U0qEq6AgAAeHIAD2ph" +
+        "dmEubGFuZy5FcnJvckUdNlaLgg5WAgAAeHIAE2phdmEubGFuZy5UaHJvd2Fi" +
+        "bGXVxjUnOXe4ywMABEwABWNhdXNlcQB+AAFMAA1kZXRhaWxNZXNzYWdldAAS" +
+        "TGphdmEvbGFuZy9TdHJpbmc7WwAKc3RhY2tUcmFjZXQAHltMamF2YS9sYW5n" +
+        "L1N0YWNrVHJhY2VFbGVtZW50O0wAFHN1cHByZXNzZWRFeGNlcHRpb25zdAAQ" +
+        "TGphdmEvdXRpbC9MaXN0O3hwcHB1cgAeW0xqYXZhLmxhbmcuU3RhY2tUcmFj" +
+        "ZUVsZW1lbnQ7AkYqPDz9IjkCAAB4cAAAAAFzcgAbamF2YS5sYW5nLlN0YWNr" +
+        "VHJhY2VFbGVtZW50YQnFmiY23YUCAAhCAAZmb3JtYXRJAApsaW5lTnVtYmVy" +
+        "TAAPY2xhc3NMb2FkZXJOYW1lcQB+AAVMAA5kZWNsYXJpbmdDbGFzc3EAfgAF" +
+        "TAAIZmlsZU5hbWVxAH4ABUwACm1ldGhvZE5hbWVxAH4ABUwACm1vZHVsZU5h" +
+        "bWVxAH4ABUwADW1vZHVsZVZlcnNpb25xAH4ABXhwAQAAAAd0AANhcHB0AARU" +
+        "ZXN0dAAJVGVzdC5qYXZhdAAEbWFpbnBwc3IAH2phdmEudXRpbC5Db2xsZWN0" +
+        "aW9ucyRFbXB0eUxpc3R6uBe0PKee3gIAAHhweHNyAB5qYXZhLmxhbmcuTnVs" +
+        "bFBvaW50ZXJFeGNlcHRpb25HpaGO/zHhuAIAAHhyABpqYXZhLmxhbmcuUnVu" +
+        "dGltZUV4Y2VwdGlvbp5fBkcKNIPlAgAAeHIAE2phdmEubGFuZy5FeGNlcHRp" +
+        "b27Q/R8+GjscxAIAAHhxAH4ABHEAfgAWdAADZm9vdXEAfgAJAAAAAXNxAH4A" +
+        "CwEAAAAHcQB+AA1xAH4ADnEAfgAPcQB+ABBwcHEAfgASeA==";
+
+    private static final String CNFE_OLD_VERSION =
+        "rO0ABXNyACBqYXZhLmxhbmcuQ2xhc3NOb3RGb3VuZEV4Y2VwdGlvbn9azWY+" +
+        "1CCOAgABTAACZXh0ABVMamF2YS9sYW5nL1Rocm93YWJsZTt4cgAmamF2YS5s" +
+        "YW5nLlJlZmxlY3RpdmVPcGVyYXRpb25FeGNlcHRpb24AAAAAB1vNFQIAAHhy" +
+        "ABNqYXZhLmxhbmcuRXhjZXB0aW9u0P0fPho7HMQCAAB4cgATamF2YS5sYW5n" +
+        "LlRocm93YWJsZdXGNSc5d7jLAwAETAAFY2F1c2VxAH4AAUwADWRldGFpbE1l" +
+        "c3NhZ2V0ABJMamF2YS9sYW5nL1N0cmluZztbAApzdGFja1RyYWNldAAeW0xq" +
+        "YXZhL2xhbmcvU3RhY2tUcmFjZUVsZW1lbnQ7TAAUc3VwcHJlc3NlZEV4Y2Vw" +
+        "dGlvbnN0ABBMamF2YS91dGlsL0xpc3Q7eHBwdAADYmFydXIAHltMamF2YS5s" +
+        "YW5nLlN0YWNrVHJhY2VFbGVtZW50OwJGKjw8/SI5AgAAeHAAAAABc3IAG2ph" +
+        "dmEubGFuZy5TdGFja1RyYWNlRWxlbWVudGEJxZomNt2FAgAIQgAGZm9ybWF0" +
+        "SQAKbGluZU51bWJlckwAD2NsYXNzTG9hZGVyTmFtZXEAfgAFTAAOZGVjbGFy" +
+        "aW5nQ2xhc3NxAH4ABUwACGZpbGVOYW1lcQB+AAVMAAptZXRob2ROYW1lcQB+" +
+        "AAVMAAptb2R1bGVOYW1lcQB+AAVMAA1tb2R1bGVWZXJzaW9ucQB+AAV4cAEA" +
+        "AAAMdAADYXBwdAAEVGVzdHQACVRlc3QuamF2YXQABG1haW5wcHNyAB9qYXZh" +
+        "LnV0aWwuQ29sbGVjdGlvbnMkRW1wdHlMaXN0ergXtDynnt4CAAB4cHhzcgAT" +
+        "amF2YS5pby5JT0V4Y2VwdGlvbmyAc2RlJfCrAgAAeHEAfgADcQB+ABV0ABJy" +
+        "ZWFkaW5nIGNsYXNzIGZpbGV1cQB+AAoAAAABc3EAfgAMAQAAAAxxAH4ADnEA" +
+        "fgAPcQB+ABBxAH4AEXBwcQB+ABN4";
+
+    private static final String ITE1_OLD_VERSION =
+        "rO0ABXNyACtqYXZhLmxhbmcucmVmbGVjdC5JbnZvY2F0aW9uVGFyZ2V0RXhj" +
+        "ZXB0aW9uOLEmjtZxJG8CAAFMAAZ0YXJnZXR0ABVMamF2YS9sYW5nL1Rocm93" +
+        "YWJsZTt4cgAmamF2YS5sYW5nLlJlZmxlY3RpdmVPcGVyYXRpb25FeGNlcHRp" +
+        "b24AAAAAB1vNFQIAAHhyABNqYXZhLmxhbmcuRXhjZXB0aW9u0P0fPho7HMQC" +
+        "AAB4cgATamF2YS5sYW5nLlRocm93YWJsZdXGNSc5d7jLAwAETAAFY2F1c2Vx" +
+        "AH4AAUwADWRldGFpbE1lc3NhZ2V0ABJMamF2YS9sYW5nL1N0cmluZztbAApz" +
+        "dGFja1RyYWNldAAeW0xqYXZhL2xhbmcvU3RhY2tUcmFjZUVsZW1lbnQ7TAAU" +
+        "c3VwcHJlc3NlZEV4Y2VwdGlvbnN0ABBMamF2YS91dGlsL0xpc3Q7eHBwdAAD" +
+        "YmFydXIAHltMamF2YS5sYW5nLlN0YWNrVHJhY2VFbGVtZW50OwJGKjw8/SI5" +
+        "AgAAeHAAAAABc3IAG2phdmEubGFuZy5TdGFja1RyYWNlRWxlbWVudGEJxZom" +
+        "Nt2FAgAIQgAGZm9ybWF0SQAKbGluZU51bWJlckwAD2NsYXNzTG9hZGVyTmFt" +
+        "ZXEAfgAFTAAOZGVjbGFyaW5nQ2xhc3NxAH4ABUwACGZpbGVOYW1lcQB+AAVM" +
+        "AAptZXRob2ROYW1lcQB+AAVMAAptb2R1bGVOYW1lcQB+AAVMAA1tb2R1bGVW" +
+        "ZXJzaW9ucQB+AAV4cAEAAAARdAADYXBwdAAEVGVzdHQACVRlc3QuamF2YXQA" +
+        "BG1haW5wcHNyAB9qYXZhLnV0aWwuQ29sbGVjdGlvbnMkRW1wdHlMaXN0ergX" +
+        "tDynnt4CAAB4cHhzcgAPamF2YS5sYW5nLkVycm9yRR02VouCDlYCAAB4cQB+" +
+        "AARxAH4AFXQAA2Zvb3VxAH4ACgAAAAFzcQB+AAwBAAAAEXEAfgAOcQB+AA9x" +
+        "AH4AEHEAfgARcHBxAH4AE3g=";
+
+    private static final String ITE2_OLD_VERSION =
+        "rO0ABXNyACtqYXZhLmxhbmcucmVmbGVjdC5JbnZvY2F0aW9uVGFyZ2V0RXhj" +
+        "ZXB0aW9uOLEmjtZxJG8CAAFMAAZ0YXJnZXR0ABVMamF2YS9sYW5nL1Rocm93" +
+        "YWJsZTt4cgAmamF2YS5sYW5nLlJlZmxlY3RpdmVPcGVyYXRpb25FeGNlcHRp" +
+        "b24AAAAAB1vNFQIAAHhyABNqYXZhLmxhbmcuRXhjZXB0aW9u0P0fPho7HMQC" +
+        "AAB4cgATamF2YS5sYW5nLlRocm93YWJsZdXGNSc5d7jLAwAETAAFY2F1c2Vx" +
+        "AH4AAUwADWRldGFpbE1lc3NhZ2V0ABJMamF2YS9sYW5nL1N0cmluZztbAApz" +
+        "dGFja1RyYWNldAAeW0xqYXZhL2xhbmcvU3RhY2tUcmFjZUVsZW1lbnQ7TAAU" +
+        "c3VwcHJlc3NlZEV4Y2VwdGlvbnN0ABBMamF2YS91dGlsL0xpc3Q7eHBwcHVy" +
+        "AB5bTGphdmEubGFuZy5TdGFja1RyYWNlRWxlbWVudDsCRio8PP0iOQIAAHhw" +
+        "AAAAAXNyABtqYXZhLmxhbmcuU3RhY2tUcmFjZUVsZW1lbnRhCcWaJjbdhQIA" +
+        "CEIABmZvcm1hdEkACmxpbmVOdW1iZXJMAA9jbGFzc0xvYWRlck5hbWVxAH4A" +
+        "BUwADmRlY2xhcmluZ0NsYXNzcQB+AAVMAAhmaWxlTmFtZXEAfgAFTAAKbWV0" +
+        "aG9kTmFtZXEAfgAFTAAKbW9kdWxlTmFtZXEAfgAFTAANbW9kdWxlVmVyc2lv" +
+        "bnEAfgAFeHABAAAAEnQAA2FwcHQABFRlc3R0AAlUZXN0LmphdmF0AARtYWlu" +
+        "cHBzcgAfamF2YS51dGlsLkNvbGxlY3Rpb25zJEVtcHR5TGlzdHq4F7Q8p57e" +
+        "AgAAeHB4c3IAD2phdmEubGFuZy5FcnJvckUdNlaLgg5WAgAAeHEAfgAEcQB+" +
+        "ABR0AANnb291cQB+AAkAAAABc3EAfgALAQAAABJxAH4ADXEAfgAOcQB+AA9x" +
+        "AH4AEHBwcQB+ABJ4";
+
+    private static final String UTE1_OLD_VERSION =
+        "rO0ABXNyAC5qYXZhLmxhbmcucmVmbGVjdC5VbmRlY2xhcmVkVGhyb3dhYmxl" +
+        "RXhjZXB0aW9uBJTY3HP5/P8CAAFMABN1bmRlY2xhcmVkVGhyb3dhYmxldAAV" +
+        "TGphdmEvbGFuZy9UaHJvd2FibGU7eHIAGmphdmEubGFuZy5SdW50aW1lRXhj" +
+        "ZXB0aW9unl8GRwo0g+UCAAB4cgATamF2YS5sYW5nLkV4Y2VwdGlvbtD9Hz4a" +
+        "OxzEAgAAeHIAE2phdmEubGFuZy5UaHJvd2FibGXVxjUnOXe4ywMABEwABWNh" +
+        "dXNlcQB+AAFMAA1kZXRhaWxNZXNzYWdldAASTGphdmEvbGFuZy9TdHJpbmc7" +
+        "WwAKc3RhY2tUcmFjZXQAHltMamF2YS9sYW5nL1N0YWNrVHJhY2VFbGVtZW50" +
+        "O0wAFHN1cHByZXNzZWRFeGNlcHRpb25zdAAQTGphdmEvdXRpbC9MaXN0O3hw" +
+        "cHQAA2JhcnVyAB5bTGphdmEubGFuZy5TdGFja1RyYWNlRWxlbWVudDsCRio8" +
+        "PP0iOQIAAHhwAAAAAXNyABtqYXZhLmxhbmcuU3RhY2tUcmFjZUVsZW1lbnRh" +
+        "CcWaJjbdhQIACEIABmZvcm1hdEkACmxpbmVOdW1iZXJMAA9jbGFzc0xvYWRl" +
+        "ck5hbWVxAH4ABUwADmRlY2xhcmluZ0NsYXNzcQB+AAVMAAhmaWxlTmFtZXEA" +
+        "fgAFTAAKbWV0aG9kTmFtZXEAfgAFTAAKbW9kdWxlTmFtZXEAfgAFTAANbW9k" +
+        "dWxlVmVyc2lvbnEAfgAFeHABAAAAE3QAA2FwcHQABFRlc3R0AAlUZXN0Lmph" +
+        "dmF0AARtYWlucHBzcgAfamF2YS51dGlsLkNvbGxlY3Rpb25zJEVtcHR5TGlz" +
+        "dHq4F7Q8p57eAgAAeHB4c3IAImphdmEubGFuZy5JbGxlZ2FsQXJndW1lbnRF" +
+        "eGNlcHRpb261iXPTfWaPvAIAAHhxAH4AAnEAfgAVdAADZm9vdXEAfgAKAAAA" +
+        "AXNxAH4ADAEAAAATcQB+AA5xAH4AD3EAfgAQcQB+ABFwcHEAfgATeA==";
+
+    private static final String UTE2_OLD_VERSION =
+        "rO0ABXNyAC5qYXZhLmxhbmcucmVmbGVjdC5VbmRlY2xhcmVkVGhyb3dhYmxl" +
+        "RXhjZXB0aW9uBJTY3HP5/P8CAAFMABN1bmRlY2xhcmVkVGhyb3dhYmxldAAV" +
+        "TGphdmEvbGFuZy9UaHJvd2FibGU7eHIAGmphdmEubGFuZy5SdW50aW1lRXhj" +
+        "ZXB0aW9unl8GRwo0g+UCAAB4cgATamF2YS5sYW5nLkV4Y2VwdGlvbtD9Hz4a" +
+        "OxzEAgAAeHIAE2phdmEubGFuZy5UaHJvd2FibGXVxjUnOXe4ywMABEwABWNh" +
+        "dXNlcQB+AAFMAA1kZXRhaWxNZXNzYWdldAASTGphdmEvbGFuZy9TdHJpbmc7" +
+        "WwAKc3RhY2tUcmFjZXQAHltMamF2YS9sYW5nL1N0YWNrVHJhY2VFbGVtZW50" +
+        "O0wAFHN1cHByZXNzZWRFeGNlcHRpb25zdAAQTGphdmEvdXRpbC9MaXN0O3hw" +
+        "cHB1cgAeW0xqYXZhLmxhbmcuU3RhY2tUcmFjZUVsZW1lbnQ7AkYqPDz9IjkC" +
+        "AAB4cAAAAAFzcgAbamF2YS5sYW5nLlN0YWNrVHJhY2VFbGVtZW50YQnFmiY2" +
+        "3YUCAAhCAAZmb3JtYXRJAApsaW5lTnVtYmVyTAAPY2xhc3NMb2FkZXJOYW1l" +
+        "cQB+AAVMAA5kZWNsYXJpbmdDbGFzc3EAfgAFTAAIZmlsZU5hbWVxAH4ABUwA" +
+        "Cm1ldGhvZE5hbWVxAH4ABUwACm1vZHVsZU5hbWVxAH4ABUwADW1vZHVsZVZl" +
+        "cnNpb25xAH4ABXhwAQAAABR0AANhcHB0AARUZXN0dAAJVGVzdC5qYXZhdAAE" +
+        "bWFpbnBwc3IAH2phdmEudXRpbC5Db2xsZWN0aW9ucyRFbXB0eUxpc3R6uBe0" +
+        "PKee3gIAAHhweHNyACJqYXZhLmxhbmcuSWxsZWdhbEFyZ3VtZW50RXhjZXB0" +
+        "aW9utYlz031mj7wCAAB4cQB+AAJxAH4AFHQAA2dvb3VxAH4ACQAAAAFzcQB+" +
+        "AAsBAAAAFHEAfgANcQB+AA5xAH4AD3EAfgAQcHBxAH4AEng=";
+
+    private static final String PAE_OLD_VERSION =
+        "rO0ABXNyACdqYXZhLnNlY3VyaXR5LlByaXZpbGVnZWRBY3Rpb25FeGNlcHRp" +
+        "b25Bj1P2UhH1ugIAAUwACWV4Y2VwdGlvbnQAFUxqYXZhL2xhbmcvRXhjZXB0" +
+        "aW9uO3hyABNqYXZhLmxhbmcuRXhjZXB0aW9u0P0fPho7HMQCAAB4cgATamF2" +
+        "YS5sYW5nLlRocm93YWJsZdXGNSc5d7jLAwAETAAFY2F1c2V0ABVMamF2YS9s" +
+        "YW5nL1Rocm93YWJsZTtMAA1kZXRhaWxNZXNzYWdldAASTGphdmEvbGFuZy9T" +
+        "dHJpbmc7WwAKc3RhY2tUcmFjZXQAHltMamF2YS9sYW5nL1N0YWNrVHJhY2VF" +
+        "bGVtZW50O0wAFHN1cHByZXNzZWRFeGNlcHRpb25zdAAQTGphdmEvdXRpbC9M" +
+        "aXN0O3hwcHB1cgAeW0xqYXZhLmxhbmcuU3RhY2tUcmFjZUVsZW1lbnQ7AkYq" +
+        "PDz9IjkCAAB4cAAAAAFzcgAbamF2YS5sYW5nLlN0YWNrVHJhY2VFbGVtZW50" +
+        "YQnFmiY23YUCAAhCAAZmb3JtYXRJAApsaW5lTnVtYmVyTAAPY2xhc3NMb2Fk" +
+        "ZXJOYW1lcQB+AAVMAA5kZWNsYXJpbmdDbGFzc3EAfgAFTAAIZmlsZU5hbWVx" +
+        "AH4ABUwACm1ldGhvZE5hbWVxAH4ABUwACm1vZHVsZU5hbWVxAH4ABUwADW1v" +
+        "ZHVsZVZlcnNpb25xAH4ABXhwAQAAABd0AANhcHB0AARUZXN0dAAJVGVzdC5q" +
+        "YXZhdAAEbWFpbnBwc3IAH2phdmEudXRpbC5Db2xsZWN0aW9ucyRFbXB0eUxp" +
+        "c3R6uBe0PKee3gIAAHhweHNyABNqYXZhLmlvLklPRXhjZXB0aW9ubIBzZGUl" +
+        "8KsCAAB4cQB+AAJxAH4AFHQAA2Zvb3VxAH4ACQAAAAFzcQB+AAsBAAAAF3EA" +
+        "fgANcQB+AA5xAH4AD3EAfgAQcHBxAH4AEng=";
+
+    private static Map<String, Throwable> SERIALIZED_DATA = Map.of(
+        EIIE_OLD_VERSION, new ExceptionInInitializerError(new NullPointerException("foo")),
+        CNFE_OLD_VERSION, new ClassNotFoundException("bar", new IOException("reading class file")),
+        ITE1_OLD_VERSION, new InvocationTargetException(new Error("foo"), "bar"),
+        ITE2_OLD_VERSION, new InvocationTargetException(new Error("goo")),
+        UTE1_OLD_VERSION, new UndeclaredThrowableException(new IllegalArgumentException("foo"), "bar"),
+        UTE2_OLD_VERSION, new UndeclaredThrowableException(new IllegalArgumentException("goo")),
+        PAE_OLD_VERSION,  new PrivilegedActionException(new IOException("foo"))
+    );
 }