src/java/org/eclipse/jetty/server/handler/ErrorHandler.java - platform/external/jetty - Git at Google

 //
 //  ========================================================================
 //  Copyright (c) 1995-2014 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.server.handler;

 import java.io.IOException;
 import java.io.PrintWriter;
 import java.io.StringWriter;
 import java.io.Writer;

 import javax.servlet.ServletException;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;

 import org.eclipse.jetty.http.HttpHeaders;
 import org.eclipse.jetty.http.HttpMethods;
 import org.eclipse.jetty.http.HttpStatus;
 import org.eclipse.jetty.http.MimeTypes;
 import org.eclipse.jetty.server.AbstractHttpConnection;
 import org.eclipse.jetty.server.Dispatcher;
 import org.eclipse.jetty.server.Request;
 import org.eclipse.jetty.util.ByteArrayISO8859Writer;
 import org.eclipse.jetty.util.log.Log;
 import org.eclipse.jetty.util.log.Logger;

 /* ------------------------------------------------------------ */
 /** Handler for Error pages
  * An ErrorHandler is registered with {@link ContextHandler#setErrorHandler(ErrorHandler)} or
  * {@link org.eclipse.jetty.server.Server#addBean(Object)}.
  * It is called by the HttpResponse.sendError method to write a error page.
  *
  */
 public class ErrorHandler extends AbstractHandler
 {
     private static final Logger LOG = Log.getLogger(ErrorHandler.class);
     public final static String ERROR_PAGE="org.eclipse.jetty.server.error_page";

     boolean _showStacks=true;
     boolean _showMessageInTitle=true;
     String _cacheControl="must-revalidate,no-cache,no-store";

     /* ------------------------------------------------------------ */
     /*
      * @see org.eclipse.jetty.server.server.Handler#handle(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse, int)
      */
     public void handle(String target, Request baseRequest, HttpServletRequest request, HttpServletResponse response) throws IOException
     {
         AbstractHttpConnection connection = AbstractHttpConnection.getCurrentConnection();
         String method = request.getMethod();
         if(!method.equals(HttpMethods.GET) && !method.equals(HttpMethods.POST) && !method.equals(HttpMethods.HEAD))
         {
             connection.getRequest().setHandled(true);
             return;
         }

         if (this instanceof ErrorPageMapper)
         {
             String error_page=((ErrorPageMapper)this).getErrorPage(request);
             if (error_page!=null && request.getServletContext()!=null)
             {
                 String old_error_page=(String)request.getAttribute(ERROR_PAGE);
                 if (old_error_page==null || !old_error_page.equals(error_page))
                 {
                     request.setAttribute(ERROR_PAGE, error_page);

                     Dispatcher dispatcher = (Dispatcher) request.getServletContext().getRequestDispatcher(error_page);
                     try
                     {
                         if(dispatcher!=null)
                         {
                             dispatcher.error(request, response);
                             return;
                         }
                         LOG.warn("No error page "+error_page);
                     }
                     catch (ServletException e)
                     {
                         LOG.warn(Log.EXCEPTION, e);
                         return;
                     }
                 }
             }
         }

         connection.getRequest().setHandled(true);
         response.setContentType(MimeTypes.TEXT_HTML_8859_1);
         if (_cacheControl!=null)
             response.setHeader(HttpHeaders.CACHE_CONTROL, _cacheControl);
         ByteArrayISO8859Writer writer= new ByteArrayISO8859Writer(4096);
         handleErrorPage(request, writer, connection.getResponse().getStatus(), connection.getResponse().getReason());
         writer.flush();
         response.setContentLength(writer.size());
         writer.writeTo(response.getOutputStream());
         writer.destroy();
     }

     /* ------------------------------------------------------------ */
     protected void handleErrorPage(HttpServletRequest request, Writer writer, int code, String message)
         throws IOException
     {
         writeErrorPage(request, writer, code, message, _showStacks);
     }

     /* ------------------------------------------------------------ */
     protected void writeErrorPage(HttpServletRequest request, Writer writer, int code, String message, boolean showStacks)
         throws IOException
     {
         if (message == null)
             message=HttpStatus.getMessage(code);

         writer.write("<html>\n<head>\n");
         writeErrorPageHead(request,writer,code,message);
         writer.write("</head>\n<body>");
         writeErrorPageBody(request,writer,code,message,showStacks);
         writer.write("\n</body>\n</html>\n");
     }

     /* ------------------------------------------------------------ */
     protected void writeErrorPageHead(HttpServletRequest request, Writer writer, int code, String message)
         throws IOException
         {
         writer.write("<meta http-equiv=\"Content-Type\" content=\"text/html; charset=ISO-8859-1\"/>\n");
         writer.write("<title>Error ");
         writer.write(Integer.toString(code));

         if (_showMessageInTitle)
         {
             writer.write(' ');
             write(writer,message);
         }
         writer.write("</title>\n");
     }

     /* ------------------------------------------------------------ */
     protected void writeErrorPageBody(HttpServletRequest request, Writer writer, int code, String message, boolean showStacks)
         throws IOException
     {
         String uri= request.getRequestURI();

         writeErrorPageMessage(request,writer,code,message,uri);
         if (showStacks)
             writeErrorPageStacks(request,writer);
         writer.write("<hr /><i><small>Powered by Jetty://</small></i>");
         for (int i= 0; i < 20; i++)
             writer.write("<br/>                                                \n");
     }

     /* ------------------------------------------------------------ */
     protected void writeErrorPageMessage(HttpServletRequest request, Writer writer, int code, String message,String uri)
     throws IOException
     {
         writer.write("<h2>HTTP ERROR ");
         writer.write(Integer.toString(code));
         writer.write("</h2>\n<p>Problem accessing ");
         write(writer,uri);
         writer.write(". Reason:\n<pre>    ");
         write(writer,message);
         writer.write("</pre></p>");
     }

     /* ------------------------------------------------------------ */
     protected void writeErrorPageStacks(HttpServletRequest request, Writer writer)
         throws IOException
     {
         Throwable th = (Throwable)request.getAttribute("javax.servlet.error.exception");
         while(th!=null)
         {
             writer.write("<h3>Caused by:</h3><pre>");
             StringWriter sw = new StringWriter();
             PrintWriter pw = new PrintWriter(sw);
             th.printStackTrace(pw);
             pw.flush();
             write(writer,sw.getBuffer().toString());
             writer.write("</pre>\n");

             th =th.getCause();
         }
     }


     /* ------------------------------------------------------------ */
     /** Get the cacheControl.
      * @return the cacheControl header to set on error responses.
      */
     public String getCacheControl()
     {
         return _cacheControl;
     }

     /* ------------------------------------------------------------ */
     /** Set the cacheControl.
      * @param cacheControl the cacheControl header to set on error responses.
      */
     public void setCacheControl(String cacheControl)
     {
         _cacheControl = cacheControl;
     }

     /* ------------------------------------------------------------ */
     /**
      * @return True if stack traces are shown in the error pages
      */
     public boolean isShowStacks()
     {
         return _showStacks;
     }

     /* ------------------------------------------------------------ */
     /**
      * @param showStacks True if stack traces are shown in the error pages
      */
     public void setShowStacks(boolean showStacks)
     {
         _showStacks = showStacks;
     }

     /* ------------------------------------------------------------ */
     /**
      * @param showMessageInTitle if true, the error message appears in page title
      */
     public void setShowMessageInTitle(boolean showMessageInTitle)
     {
         _showMessageInTitle = showMessageInTitle;
     }


     /* ------------------------------------------------------------ */
     public boolean getShowMessageInTitle()
     {
         return _showMessageInTitle;
     }

     /* ------------------------------------------------------------ */
     protected void write(Writer writer,String string)
         throws IOException
     {
         if (string==null)
             return;

         for (int i=0;i<string.length();i++)
         {
             char c=string.charAt(i);

             switch(c)
             {
                 case '&' :
                     writer.write("&amp;");
                     break;
                 case '<' :
                     writer.write("&lt;");
                     break;
                 case '>' :
                     writer.write("&gt;");
                     break;

                 default:
                     if (Character.isISOControl(c) && !Character.isWhitespace(c))
                         writer.write('?');
                     else
                         writer.write(c);
             }
         }
     }

     /* ------------------------------------------------------------ */
     public interface ErrorPageMapper
     {
         String getErrorPage(HttpServletRequest request);
     }
 }
	//
	// ========================================================================
	// Copyright (c) 1995-2014 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.server.handler;

	import java.io.IOException;
	import java.io.PrintWriter;
	import java.io.StringWriter;
	import java.io.Writer;

	import javax.servlet.ServletException;
	import javax.servlet.http.HttpServletRequest;
	import javax.servlet.http.HttpServletResponse;

	import org.eclipse.jetty.http.HttpHeaders;
	import org.eclipse.jetty.http.HttpMethods;
	import org.eclipse.jetty.http.HttpStatus;
	import org.eclipse.jetty.http.MimeTypes;
	import org.eclipse.jetty.server.AbstractHttpConnection;
	import org.eclipse.jetty.server.Dispatcher;
	import org.eclipse.jetty.server.Request;
	import org.eclipse.jetty.util.ByteArrayISO8859Writer;
	import org.eclipse.jetty.util.log.Log;
	import org.eclipse.jetty.util.log.Logger;

	/* ------------------------------------------------------------ */
	/** Handler for Error pages
	* An ErrorHandler is registered with {@link ContextHandler#setErrorHandler(ErrorHandler)} or
	* {@link org.eclipse.jetty.server.Server#addBean(Object)}.
	* It is called by the HttpResponse.sendError method to write a error page.
	*
	*/
	public class ErrorHandler extends AbstractHandler
	{
	private static final Logger LOG = Log.getLogger(ErrorHandler.class);
	public final static String ERROR_PAGE="org.eclipse.jetty.server.error_page";

	boolean _showStacks=true;
	boolean _showMessageInTitle=true;
	String _cacheControl="must-revalidate,no-cache,no-store";

	/* ------------------------------------------------------------ */
	/*
	* @see org.eclipse.jetty.server.server.Handler#handle(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse, int)
	*/
	public void handle(String target, Request baseRequest, HttpServletRequest request, HttpServletResponse response) throws IOException
	{
	AbstractHttpConnection connection = AbstractHttpConnection.getCurrentConnection();
	String method = request.getMethod();
	if(!method.equals(HttpMethods.GET) && !method.equals(HttpMethods.POST) && !method.equals(HttpMethods.HEAD))
	{
	connection.getRequest().setHandled(true);
	return;
	}

	if (this instanceof ErrorPageMapper)
	{
	String error_page=((ErrorPageMapper)this).getErrorPage(request);
	if (error_page!=null && request.getServletContext()!=null)
	{
	String old_error_page=(String)request.getAttribute(ERROR_PAGE);
	if (old_error_page==null \|\| !old_error_page.equals(error_page))
	{
	request.setAttribute(ERROR_PAGE, error_page);

	Dispatcher dispatcher = (Dispatcher) request.getServletContext().getRequestDispatcher(error_page);
	try
	{
	if(dispatcher!=null)
	{
	dispatcher.error(request, response);
	return;
	}
	LOG.warn("No error page "+error_page);
	}
	catch (ServletException e)
	{
	LOG.warn(Log.EXCEPTION, e);
	return;
	}
	}
	}
	}

	connection.getRequest().setHandled(true);
	response.setContentType(MimeTypes.TEXT_HTML_8859_1);
	if (_cacheControl!=null)
	response.setHeader(HttpHeaders.CACHE_CONTROL, _cacheControl);
	ByteArrayISO8859Writer writer= new ByteArrayISO8859Writer(4096);
	handleErrorPage(request, writer, connection.getResponse().getStatus(), connection.getResponse().getReason());
	writer.flush();
	response.setContentLength(writer.size());
	writer.writeTo(response.getOutputStream());
	writer.destroy();
	}

	/* ------------------------------------------------------------ */
	protected void handleErrorPage(HttpServletRequest request, Writer writer, int code, String message)
	throws IOException
	{
	writeErrorPage(request, writer, code, message, _showStacks);
	}

	/* ------------------------------------------------------------ */
	protected void writeErrorPage(HttpServletRequest request, Writer writer, int code, String message, boolean showStacks)
	throws IOException
	{
	if (message == null)
	message=HttpStatus.getMessage(code);

	writer.write("<html>\n<head>\n");
	writeErrorPageHead(request,writer,code,message);
	writer.write("</head>\n<body>");
	writeErrorPageBody(request,writer,code,message,showStacks);
	writer.write("\n</body>\n</html>\n");
	}

	/* ------------------------------------------------------------ */
	protected void writeErrorPageHead(HttpServletRequest request, Writer writer, int code, String message)
	throws IOException
	{
	writer.write("<meta http-equiv=\"Content-Type\" content=\"text/html; charset=ISO-8859-1\"/>\n");
	writer.write("<title>Error ");
	writer.write(Integer.toString(code));

	if (_showMessageInTitle)
	{
	writer.write(' ');
	write(writer,message);
	}
	writer.write("</title>\n");
	}

	/* ------------------------------------------------------------ */
	protected void writeErrorPageBody(HttpServletRequest request, Writer writer, int code, String message, boolean showStacks)
	throws IOException
	{
	String uri= request.getRequestURI();

	writeErrorPageMessage(request,writer,code,message,uri);
	if (showStacks)
	writeErrorPageStacks(request,writer);
	writer.write("<hr /><i><small>Powered by Jetty://</small></i>");
	for (int i= 0; i < 20; i++)
	writer.write("<br/> \n");
	}

	/* ------------------------------------------------------------ */
	protected void writeErrorPageMessage(HttpServletRequest request, Writer writer, int code, String message,String uri)
	throws IOException
	{
	writer.write("<h2>HTTP ERROR ");
	writer.write(Integer.toString(code));
	writer.write("</h2>\n<p>Problem accessing ");
	write(writer,uri);
	writer.write(". Reason:\n<pre> ");
	write(writer,message);
	writer.write("</pre></p>");
	}

	/* ------------------------------------------------------------ */
	protected void writeErrorPageStacks(HttpServletRequest request, Writer writer)
	throws IOException
	{
	Throwable th = (Throwable)request.getAttribute("javax.servlet.error.exception");
	while(th!=null)
	{
	writer.write("<h3>Caused by:</h3><pre>");
	StringWriter sw = new StringWriter();
	PrintWriter pw = new PrintWriter(sw);
	th.printStackTrace(pw);
	pw.flush();
	write(writer,sw.getBuffer().toString());
	writer.write("</pre>\n");

	th =th.getCause();
	}
	}


	/* ------------------------------------------------------------ */
	/** Get the cacheControl.
	* @return the cacheControl header to set on error responses.
	*/
	public String getCacheControl()
	{
	return _cacheControl;
	}

	/* ------------------------------------------------------------ */
	/** Set the cacheControl.
	* @param cacheControl the cacheControl header to set on error responses.
	*/
	public void setCacheControl(String cacheControl)
	{
	_cacheControl = cacheControl;
	}

	/* ------------------------------------------------------------ */
	/**
	* @return True if stack traces are shown in the error pages
	*/
	public boolean isShowStacks()
	{
	return _showStacks;
	}

	/* ------------------------------------------------------------ */
	/**
	* @param showStacks True if stack traces are shown in the error pages
	*/
	public void setShowStacks(boolean showStacks)
	{
	_showStacks = showStacks;
	}

	/* ------------------------------------------------------------ */
	/**
	* @param showMessageInTitle if true, the error message appears in page title
	*/
	public void setShowMessageInTitle(boolean showMessageInTitle)
	{
	_showMessageInTitle = showMessageInTitle;
	}


	/* ------------------------------------------------------------ */
	public boolean getShowMessageInTitle()
	{
	return _showMessageInTitle;
	}

	/* ------------------------------------------------------------ */
	protected void write(Writer writer,String string)
	throws IOException
	{
	if (string==null)
	return;

	for (int i=0;i<string.length();i++)
	{
	char c=string.charAt(i);

	switch(c)
	{
	case '&' :
	writer.write("&");
	break;
	case '<' :
	writer.write("<");
	break;
	case '>' :
	writer.write(">");
	break;

	default:
	if (Character.isISOControl(c) && !Character.isWhitespace(c))
	writer.write('?');
	else
	writer.write(c);
	}
	}
	}

	/* ------------------------------------------------------------ */
	public interface ErrorPageMapper
	{
	String getErrorPage(HttpServletRequest request);
	}
	}