/*
 * Copyright 2010 Google Inc.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */

package com.google.gwt.core.client.impl;

import java.io.Serializable;

/**
 * The emulated Throwable class does not serialize Throwables recursively and
 * does not serialize the stack trace.  This class is an alternative, and
 * can be used by writing a custom serializer for the class which contains a
 * Throwable. See {@link LogRecord_CustomFieldSerializer} as an example.
 *
 */
public class SerializableThrowable implements Serializable {
  private SerializableThrowable cause = null;
  private String message = null;
  private StackTraceElement[] stackTrace = null;
  private String typeName = null;

  /**
   * A subclass of Throwable that contains the serialized exception class type.
   */
  public static class ThrowableWithClassName extends Throwable {

    private String typeName;

    public ThrowableWithClassName(String message, Throwable cause, String typeName) {
      super(message, cause);
      this.typeName = typeName;
    }

    public ThrowableWithClassName(String message, String typeName) {
      super(message);
      this.typeName = typeName;
    }

    public String getExceptionClass() {
      return typeName;
    }
  }

  /**
   * Create a new SerializableThrowable from a Throwable.
   */
  public SerializableThrowable(Throwable t) {
    message = t.getMessage();
    if (t.getCause() != null && t.getCause() != t) {
      cause = new SerializableThrowable(t.getCause());
    }
    stackTrace = t.getStackTrace();
    typeName = t.getClass().getName();
  }
  
  protected SerializableThrowable() {
    // for serialization
  }
  
  public SerializableThrowable getCause() {
    return cause;
  }
  
  public String getMessage() {
    return message;
  }
  
  public StackTraceElement[] getStackTrace() {
    return stackTrace;
  }

  /**
   * Create a new Throwable from this SerializableThrowable.
   */
  public Throwable getThrowable() {
    Throwable t;
    if (cause != null) {
      t = new ThrowableWithClassName(message, cause.getThrowable(), typeName);
    } else {
      t = new ThrowableWithClassName(message, typeName);
    }
    t.setStackTrace(stackTrace);
    return t;
  }
  
  public void setCause(SerializableThrowable c) {
    cause = c;
  }
  
  public void setMessage(String msg) {
    message = msg;
  }
  
  public void setStackTrace(StackTraceElement[] st) {
    stackTrace = st;
  }
}