// ========================================================================
   // Copyright (c) 1999-2009 Mort Bay Consulting Pty. Ltd.
   // ------------------------------------------------------------------------
   // All rights reserved. This program and the accompanying materials
   // are made available under the terms of the Eclipse Public License v1.0
   // and Apache License v2.0 which accompanies this distribution.
   // The Eclipse Public License is available at 
   // http://www.eclipse.org/legal/epl-v10.html
   // The Apache License v2.0 is available at
  // http://www.opensource.org/licenses/apache2.0.php
  // You may elect to redistribute this code under either of these licenses. 
  // ========================================================================
  
  package org.eclipse.jetty.util;
  import java.io.PrintStream;
  import java.io.PrintWriter;
  import java.util.List;
  
  
  /* ------------------------------------------------------------ */
  /** Wraps multiple exceptions.
   *
   * Allows multiple exceptions to be thrown as a single exception.
   *
   * 
   */
  @SuppressWarnings("serial")
  public class MultiException extends Exception
  {
      private Object nested;
  
      /* ------------------------------------------------------------ */
      public MultiException()
      {
          super("Multiple exceptions");
      }
  
      /* ------------------------------------------------------------ */
      public void add(Throwable e)
      {
          if (e instanceof MultiException)
          {
              MultiException me = (MultiException)e;
              for (int i=0;i<LazyList.size(me.nested);i++)
                  nested=LazyList.add(nested,LazyList.get(me.nested,i));
          }
          else
              nested=LazyList.add(nested,e);
      }
  
      /* ------------------------------------------------------------ */
      public int size()
      {
          return LazyList.size(nested);
      }
      
      /* ------------------------------------------------------------ */
      public List<Throwable> getThrowables()
      {
          return LazyList.getList(nested);
      }
      
      /* ------------------------------------------------------------ */
      public Throwable getThrowable(int i)
      {
          return (Throwable) LazyList.get(nested,i);
      }
  
      /* ------------------------------------------------------------ */
      /** Throw a multiexception.
       * If this multi exception is empty then no action is taken. If it
       * contains a single exception that is thrown, otherwise the this
       * multi exception is thrown. 
       * @exception Exception 
       */
      public void ifExceptionThrow()
          throws Exception
      {
          switch (LazyList.size(nested))
          {
            case 0:
                break;
            case 1:
                Throwable th=(Throwable)LazyList.get(nested,0);
                if (th instanceof Error)
                    throw (Error)th;
                if (th instanceof Exception)
                    throw (Exception)th;
            default:
                throw this;
          }
      }
      
      /* ------------------------------------------------------------ */
      /** Throw a Runtime exception.
       * If this multi exception is empty then no action is taken. If it
       * contains a single error or runtime exception that is thrown, otherwise the this
       * multi exception is thrown, wrapped in a runtime exception. 
       * @exception Error If this exception contains exactly 1 {@link Error} 
      * @exception RuntimeException If this exception contains 1 {@link Throwable} but it is not an error,
      *                             or it contains more than 1 {@link Throwable} of any type.
      */
     public void ifExceptionThrowRuntime()
         throws Error
     {
         switch (LazyList.size(nested))
         {
           case 0:
               break;
           case 1:
               Throwable th=(Throwable)LazyList.get(nested,0);
               if (th instanceof Error)
                   throw (Error)th;
               else if (th instanceof RuntimeException)
                   throw (RuntimeException)th;
               else
                   throw new RuntimeException(th);
           default:
               throw new RuntimeException(this);
         }
     }
     
     /* ------------------------------------------------------------ */
     /** Throw a multiexception.
      * If this multi exception is empty then no action is taken. If it
      * contains a any exceptions then this
      * multi exception is thrown. 
      */
     public void ifExceptionThrowMulti()
         throws MultiException
     {
         if (LazyList.size(nested)>0)
             throw this;
     }
 
     /* ------------------------------------------------------------ */
     @Override
     public String toString()
     {
         if (LazyList.size(nested)>0)
             return MultiException.class.getSimpleName()+
                 LazyList.getList(nested);
         return MultiException.class.getSimpleName()+"[]";
     }
 
     /* ------------------------------------------------------------ */
     @Override
     public void printStackTrace()
     {
         super.printStackTrace();
         for (int i=0;i<LazyList.size(nested);i++)
             ((Throwable)LazyList.get(nested,i)).printStackTrace();
     }
    
 
     /* ------------------------------------------------------------------------------- */
     /**
      * @see java.lang.Throwable#printStackTrace(java.io.PrintStream)
      */
     @Override
     public void printStackTrace(PrintStream out)
     {
         super.printStackTrace(out);
         for (int i=0;i<LazyList.size(nested);i++)
             ((Throwable)LazyList.get(nested,i)).printStackTrace(out);
     }
 
     /* ------------------------------------------------------------------------------- */
     /**
      * @see java.lang.Throwable#printStackTrace(java.io.PrintWriter)
      */
     @Override
     public void printStackTrace(PrintWriter out)
     {
         super.printStackTrace(out);
         for (int i=0;i<LazyList.size(nested);i++)
             ((Throwable)LazyList.get(nested,i)).printStackTrace(out);
     }
 
 }