/*
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you 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 org.apache.chemistry.opencmis.server.shared;
  
  import org.w3c.dom.Document;
  import org.w3c.dom.Element;
  import org.w3c.dom.Node;
  
  import java.io.PrintWriter;
  import java.io.StringWriter;
  
  import javax.xml.parsers.DocumentBuilder;
  import javax.xml.parsers.DocumentBuilderFactory;
  
  
  public class ExceptionHelper
  {
      public static final String STACK_TRACE_PROPERTY = "org.apache.chemistry.opencmis.stacktrace.disable";
      private static final boolean sendStackTrace;
  
      static
      {
          sendStackTrace = System.getProperty( STACK_TRACE_PROPERTY ) == null;
      }
  
      private ExceptionHelper(  )
      {
      }
  
      /**
       * Returns the stack trace as string.
       */
      public static String getStacktraceAsString( Throwable t )
      {
          if ( !sendStackTrace || ( t == null ) )
          {
              return null;
          }
  
          StringWriter sw = new StringWriter(  );
          PrintWriter pw = new PrintWriter( sw );
  
          t.printStackTrace( pw );
  
          return sw.toString(  );
      }
  
      /**
       * Returns the stack trace as DOM node.
       */
      public static Node getStacktraceAsNode( Throwable t )
      {
          try
          {
              String st = getStacktraceAsString( t );
  
              if ( st != null )
              {
                  DocumentBuilderFactory dbfac = DocumentBuilderFactory.newInstance(  );
                  DocumentBuilder docBuilder = dbfac.newDocumentBuilder(  );
                  Document doc = docBuilder.newDocument(  );
  
                  Element node = doc.createElementNS( "http://chemistry.apache.org/opencmis/exception", "stacktrace" );
                  doc.appendChild( node );
  
                  node.appendChild( doc.createTextNode( st ) );
  
                  return node;
              }
          }
          catch ( Exception e )
          {
          }
  
          return null;
      }
  }