/*

 * reserved comment block

 * DO NOT REMOVE OR ALTER!

 */

/*

 * Copyright 1999-2004 The Apache Software Foundation.

 *

 * 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.

 */

/*

 * $Id: XPathException.java,v 1.3 2005/09/28 13:49:30 pvedula Exp $

 */

package com.sun.org.apache.xpath.internal;

import javax.xml.transform.TransformerException;

import org.w3c.dom.Node;

/**

 * This class implements an exception object that all

 * XPath classes will throw in case of an error.  This class

 * extends TransformerException, and may hold other exceptions. In the

 * case of nested exceptions, printStackTrace will dump

 * all the traces of the nested exceptions, not just the trace

 * of this object.

 * @xsl.usage general

 */

public class XPathException extends TransformerException

{

    static final long serialVersionUID = 4263549717619045963L;

  /** The home of the expression that caused the error.

   *  @serial  */

  Object m_styleNode = null;

  /**

   * Get the stylesheet node from where this error originated.

   * @return The stylesheet node from where this error originated, or null.

   */

  public Object getStylesheetNode()

  {

    return m_styleNode;

  }

  /**

   * Set the stylesheet node from where this error originated.

   * @param styleNode The stylesheet node from where this error originated, or null.

   */

  public void setStylesheetNode(Object styleNode)

  {

    m_styleNode = styleNode;

  }

  /** A nested exception.

   *  @serial   */

  protected Exception m_exception;

  /**

   * Create an XPathException object that holds

   * an error message.

   * @param message The error message.

   */

  public XPathException(String message, ExpressionNode ex)

  {

    super(message);

    this.setLocator(ex);

    setStylesheetNode(getStylesheetNode(ex));

  }

  /**

   * Create an XPathException object that holds

   * an error message.

   * @param message The error message.

   */

  public XPathException(String message)

  {

    super(message);

  }

  /**

   * Get the XSLT ElemVariable that this sub-expression references.  In order for

   * this to work, the SourceLocator must be the owning ElemTemplateElement.

   * @return The dereference to the ElemVariable, or null if not found.

   */

  public org.w3c.dom.Node getStylesheetNode(ExpressionNode ex)

  {

    ExpressionNode owner = getExpressionOwner(ex);

    if (null != owner && owner instanceof org.w3c.dom.Node)

    {

                return ((org.w3c.dom.Node)owner);

    }

    return null;

  }

  /**

   * Get the first non-Expression parent of this node.

   * @return null or first ancestor that is not an Expression.

   */

  protected ExpressionNode getExpressionOwner(ExpressionNode ex)

  {

        ExpressionNode parent = ex.exprGetParent();

        while((null != parent) && (parent instanceof Expression))

                parent = parent.exprGetParent();

        return parent;

  }

  /**

   * Create an XPathException object that holds

   * an error message and the stylesheet node that

   * the error originated from.

   * @param message The error message.

   * @param styleNode The stylesheet node that the error originated from.

   */

  public XPathException(String message, Object styleNode)

  {

    super(message);

    m_styleNode = styleNode;

  }

  /**

   * Create an XPathException object that holds

   * an error message, the stylesheet node that

   * the error originated from, and another exception

   * that caused this exception.

   * @param message The error message.

   * @param styleNode The stylesheet node that the error originated from.

   * @param e The exception that caused this exception.

   */

  public XPathException(String message, Node styleNode, Exception e)

  {

    super(message);

    m_styleNode = styleNode;

    this.m_exception = e;

  }

  /**

   * Create an XPathException object that holds

   * an error message, and another exception

   * that caused this exception.

   * @param message The error message.

   * @param e The exception that caused this exception.

   */

  public XPathException(String message, Exception e)

  {

    super(message);

    this.m_exception = e;

  }

  /**

   * Print the the trace of methods from where the error

   * originated.  This will trace all nested exception

   * objects, as well as this object.

   * @param s The stream where the dump will be sent to.

   */

  public void printStackTrace(java.io.PrintStream s)

  {

    if (s == null)

      s = System.err;

    try

    {

      super.printStackTrace(s);

    }

    catch (Exception e){}

    Throwable exception = m_exception;

    for (int i = 0; (i < 10) && (null != exception); i++)

    {

      s.println("---------");

      exception.printStackTrace(s);

      if (exception instanceof TransformerException)

      {

        TransformerException se = (TransformerException) exception;

        Throwable prev = exception;

        exception = se.getException();

        if (prev == exception)

          break;

      }

      else

      {

        exception = null;

      }

    }

  }

  /**

   * Find the most contained message.

   *

   * @return The error message of the originating exception.

   */

  public String getMessage()

  {

    String lastMessage = super.getMessage();

    Throwable exception = m_exception;

    while (null != exception)

    {

      String nextMessage = exception.getMessage();

      if (null != nextMessage)

        lastMessage = nextMessage;

      if (exception instanceof TransformerException)

      {

        TransformerException se = (TransformerException) exception;

        Throwable prev = exception;

        exception = se.getException();

        if (prev == exception)

          break;

      }

      else

      {

        exception = null;

      }

    }

    return (null != lastMessage) ? lastMessage : "";

  }

  /**

   * Print the the trace of methods from where the error

   * originated.  This will trace all nested exception

   * objects, as well as this object.

   * @param s The writer where the dump will be sent to.

   */

  public void printStackTrace(java.io.PrintWriter s)

  {

    if (s == null)

      s = new java.io.PrintWriter(System.err);

    try

    {

      super.printStackTrace(s);

    }

    catch (Exception e){}

    boolean isJdk14OrHigher = false;

    try {

        Throwable.class.getMethod("getCause", (Class[]) null);

        isJdk14OrHigher = true;

    } catch (NoSuchMethodException nsme) {

        // do nothing

    }

    // The printStackTrace method of the Throwable class in jdk 1.4

    // and higher will include the cause when printing the backtrace.

    // The following code is only required when using jdk 1.3 or lower

    if (!isJdk14OrHigher) {

      Throwable exception = m_exception;

      for (int i = 0; (i < 10) && (null != exception); i++)

      {

        s.println("---------");

        try

        {

          exception.printStackTrace(s);

        }

        catch (Exception e)

        {

          s.println("Could not print stack trace...");

        }

        if (exception instanceof TransformerException)

        {

          TransformerException se = (TransformerException) exception;

          Throwable prev = exception;

          exception = se.getException();

          if (prev == exception)

          {

            exception = null;

            break;

          }

        }

        else

        {

          exception = null;

        }

      }

    }

  }

  /**

   *  Return the embedded exception, if any.

   *  Overrides javax.xml.transform.TransformerException.getException().

   *

   *  @return The embedded exception, or null if there is none.

   */

  public Throwable getException()

  {

    return m_exception;

  }

}