java/org/apache/catalina/valves/ErrorReportValve.java - tomcat - Git at Google

 /*
  * 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.catalina.valves;

 import java.io.File;
 import java.io.FileInputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
 import java.io.Writer;
 import java.util.Scanner;
 import java.util.concurrent.atomic.AtomicBoolean;

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

 import org.apache.catalina.connector.Request;
 import org.apache.catalina.connector.Response;
 import org.apache.catalina.util.ErrorPageSupport;
 import org.apache.catalina.util.IOTools;
 import org.apache.catalina.util.ServerInfo;
 import org.apache.catalina.util.TomcatCSS;
 import org.apache.coyote.ActionCode;
 import org.apache.tomcat.util.ExceptionUtils;
 import org.apache.tomcat.util.descriptor.web.ErrorPage;
 import org.apache.tomcat.util.res.StringManager;
 import org.apache.tomcat.util.security.Escape;

 /**
  * <p>Implementation of a Valve that outputs HTML error pages.</p>
  *
  * <p>This Valve should be attached at the Host level, although it will work
  * if attached to a Context.</p>
  *
  * <p>HTML code from the Cocoon 2 project.</p>
  *
  * @author Remy Maucherat
  * @author Craig R. McClanahan
  * @author <a href="mailto:nicolaken@supereva.it">Nicola Ken Barozzi</a> Aisa
  * @author <a href="mailto:stefano@apache.org">Stefano Mazzocchi</a>
  * @author Yoav Shapira
  */
 public class ErrorReportValve extends ValveBase {

     private boolean showReport = true;

     private boolean showServerInfo = true;

     private final ErrorPageSupport errorPageSupport = new ErrorPageSupport();


     //------------------------------------------------------ Constructor

     public ErrorReportValve() {
         super(true);
     }


     // --------------------------------------------------------- Public Methods

     /**
      * Invoke the next Valve in the sequence. When the invoke returns, check
      * the response state. If the status code is greater than or equal to 400
      * or an uncaught exception was thrown then the error handling will be
      * triggered.
      *
      * @param request The servlet request to be processed
      * @param response The servlet response to be created
      *
      * @exception IOException if an input/output error occurs
      * @exception ServletException if a servlet error occurs
      */
     @Override
     public void invoke(Request request, Response response) throws IOException, ServletException {

         // Perform the request
         getNext().invoke(request, response);

         if (response.isCommitted()) {
             if (response.setErrorReported()) {
                 // Error wasn't previously reported but we can't write an error
                 // page because the response has already been committed. Attempt
                 // to flush any data that is still to be written to the client.
                 try {
                     response.flushBuffer();
                 } catch (Throwable t) {
                     ExceptionUtils.handleThrowable(t);
                 }
                 // Close immediately to signal to the client that something went
                 // wrong
                 response.getCoyoteResponse().action(ActionCode.CLOSE_NOW,
                         request.getAttribute(RequestDispatcher.ERROR_EXCEPTION));
             }
             return;
         }

         Throwable throwable = (Throwable) request.getAttribute(RequestDispatcher.ERROR_EXCEPTION);

         // If an async request is in progress and is not going to end once this
         // container thread finishes, do not process any error page here.
         if (request.isAsync() && !request.isAsyncCompleting()) {
             return;
         }

         if (throwable != null && !response.isError()) {
             // Make sure that the necessary methods have been called on the
             // response. (It is possible a component may just have set the
             // Throwable. Tomcat won't do that but other components might.)
             // These are safe to call at this point as we know that the response
             // has not been committed.
             response.reset();
             response.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
         }

         // One way or another, response.sendError() will have been called before
         // execution reaches this point and suspended the response. Need to
         // reverse that so this valve can write to the response.
         response.setSuspended(false);

         try {
             report(request, response, throwable);
         } catch (Throwable tt) {
             ExceptionUtils.handleThrowable(tt);
         }
     }


     // ------------------------------------------------------ Protected Methods


     /**
      * Prints out an error report.
      *
      * @param request The request being processed
      * @param response The response being generated
      * @param throwable The exception that occurred (which possibly wraps
      *  a root cause exception
      */
     protected void report(Request request, Response response, Throwable throwable) {

         int statusCode = response.getStatus();

         // Do nothing on a 1xx, 2xx and 3xx status
         // Do nothing if anything has been written already
         // Do nothing if the response hasn't been explicitly marked as in error
         //    and that error has not been reported.
         if (statusCode < 400 || response.getContentWritten() > 0 || !response.setErrorReported()) {
             return;
         }

         // If an error has occurred that prevents further I/O, don't waste time
         // producing an error report that will never be read
         AtomicBoolean result = new AtomicBoolean(false);
         response.getCoyoteResponse().action(ActionCode.IS_IO_ALLOWED, result);
         if (!result.get()) {
             return;
         }

         ErrorPage errorPage = null;
         if (throwable != null) {
             errorPage = errorPageSupport.find(throwable);
         }
         if (errorPage == null) {
             errorPage = errorPageSupport.find(statusCode);
         }
         if (errorPage == null) {
             // Default error page
             errorPage = errorPageSupport.find(0);
         }


         if (errorPage != null) {
             if (sendErrorPage(errorPage.getLocation(), response)) {
                 // If the page was sent successfully, don't write the standard
                 // error page.
                 return;
             }
         }

         String message = Escape.htmlElementContent(response.getMessage());
         if (message == null) {
             if (throwable != null) {
                 String exceptionMessage = throwable.getMessage();
                 if (exceptionMessage != null && exceptionMessage.length() > 0) {
                     message = Escape.htmlElementContent((new Scanner(exceptionMessage)).nextLine());
                 }
             }
             if (message == null) {
                 message = "";
             }
         }

         // Do nothing if there is no reason phrase for the specified status code and
         // no error message provided
         String reason = null;
         String description = null;
         StringManager smClient = StringManager.getManager(
                 Constants.Package, request.getLocales());
         response.setLocale(smClient.getLocale());
         try {
             reason = smClient.getString("http." + statusCode + ".reason");
             description = smClient.getString("http." + statusCode + ".desc");
         } catch (Throwable t) {
             ExceptionUtils.handleThrowable(t);
         }
         if (reason == null || description == null) {
             if (message.isEmpty()) {
                 return;
             } else {
                 reason = smClient.getString("errorReportValve.unknownReason");
                 description = smClient.getString("errorReportValve.noDescription");
             }
         }

         StringBuilder sb = new StringBuilder();

         sb.append("<!doctype html><html lang=\"");
         sb.append(smClient.getLocale().getLanguage()).append("\">");
         sb.append("<head>");
         sb.append("<title>");
         sb.append(smClient.getString("errorReportValve.statusHeader",
                 String.valueOf(statusCode), reason));
         sb.append("</title>");
         sb.append("<style type=\"text/css\">");
         sb.append(TomcatCSS.TOMCAT_CSS);
         sb.append("</style>");
         sb.append("</head><body>");
         sb.append("<h1>");
         sb.append(smClient.getString("errorReportValve.statusHeader",
                 String.valueOf(statusCode), reason)).append("</h1>");
         if (isShowReport()) {
             sb.append("<hr class=\"line\" />");
             sb.append("<p><b>");
             sb.append(smClient.getString("errorReportValve.type"));
             sb.append("</b> ");
             if (throwable != null) {
                 sb.append(smClient.getString("errorReportValve.exceptionReport"));
             } else {
                 sb.append(smClient.getString("errorReportValve.statusReport"));
             }
             sb.append("</p>");
             if (!message.isEmpty()) {
                 sb.append("<p><b>");
                 sb.append(smClient.getString("errorReportValve.message"));
                 sb.append("</b> ");
                 sb.append(message).append("</p>");
             }
             sb.append("<p><b>");
             sb.append(smClient.getString("errorReportValve.description"));
             sb.append("</b> ");
             sb.append(description);
             sb.append("</p>");
             if (throwable != null) {
                 String stackTrace = getPartialServletStackTrace(throwable);
                 sb.append("<p><b>");
                 sb.append(smClient.getString("errorReportValve.exception"));
                 sb.append("</b></p><pre>");
                 sb.append(Escape.htmlElementContent(stackTrace));
                 sb.append("</pre>");

                 int loops = 0;
                 Throwable rootCause = throwable.getCause();
                 while (rootCause != null && (loops < 10)) {
                     stackTrace = getPartialServletStackTrace(rootCause);
                     sb.append("<p><b>");
                     sb.append(smClient.getString("errorReportValve.rootCause"));
                     sb.append("</b></p><pre>");
                     sb.append(Escape.htmlElementContent(stackTrace));
                     sb.append("</pre>");
                     // In case root cause is somehow heavily nested
                     rootCause = rootCause.getCause();
                     loops++;
                 }

                 sb.append("<p><b>");
                 sb.append(smClient.getString("errorReportValve.note"));
                 sb.append("</b> ");
                 sb.append(smClient.getString("errorReportValve.rootCauseInLogs"));
                 sb.append("</p>");

             }
             sb.append("<hr class=\"line\" />");
         }
         if (isShowServerInfo()) {
             sb.append("<h3>").append(ServerInfo.getServerInfo()).append("</h3>");
         }
         sb.append("</body></html>");

         try {
             try {
                 response.setContentType("text/html");
                 response.setCharacterEncoding("utf-8");
             } catch (Throwable t) {
                 ExceptionUtils.handleThrowable(t);
                 if (container.getLogger().isDebugEnabled()) {
                     container.getLogger().debug("status.setContentType", t);
                 }
             }
             Writer writer = response.getReporter();
             if (writer != null) {
                 // If writer is null, it's an indication that the response has
                 // been hard committed already, which should never happen
                 writer.write(sb.toString());
                 response.finishResponse();
             }
         } catch (IOException e) {
             // Ignore
         } catch (IllegalStateException e) {
             // Ignore
         }

     }


     /**
      * Print out a partial servlet stack trace (truncating at the last
      * occurrence of javax.servlet.).
      * @param t The stack trace to process
      * @return the stack trace relative to the application layer
      */
     protected String getPartialServletStackTrace(Throwable t) {
         StringBuilder trace = new StringBuilder();
         trace.append(t.toString()).append(System.lineSeparator());
         StackTraceElement[] elements = t.getStackTrace();
         int pos = elements.length;
         for (int i = elements.length - 1; i >= 0; i--) {
             if ((elements[i].getClassName().startsWith
                  ("org.apache.catalina.core.ApplicationFilterChain"))
                 && (elements[i].getMethodName().equals("internalDoFilter"))) {
                 pos = i;
                 break;
             }
         }
         for (int i = 0; i < pos; i++) {
             if (!(elements[i].getClassName().startsWith
                   ("org.apache.catalina.core."))) {
                 trace.append('\t').append(elements[i].toString()).append(System.lineSeparator());
             }
         }
         return trace.toString();
     }


     private boolean sendErrorPage(String location, Response response) {
         File file = new File(location);
         if (!file.isAbsolute()) {
             file = new File(getContainer().getCatalinaBase(), location);
         }
         if (!file.isFile() || !file.canRead()) {
             getContainer().getLogger().warn(
                     sm.getString("errorReportValve.errorPageNotFound", location));
             return false;
         }

         // Hard coded for now. Consider making this optional. At Valve level or
         // page level?
         response.setContentType("text/html");
         response.setCharacterEncoding("UTF-8");

         try (OutputStream os = response.getOutputStream();
                 InputStream is = new FileInputStream(file);){
             IOTools.flow(is, os);
         } catch (IOException e) {
             getContainer().getLogger().warn(
                     sm.getString("errorReportValve.errorPageIOException", location), e);
             return false;
         }

         return true;
     }


     /**
      * Enables/Disables full error reports
      *
      * @param showReport <code>true</code> to show full error data
      */
     public void setShowReport(boolean showReport) {
         this.showReport = showReport;
     }

     public boolean isShowReport() {
         return showReport;
     }

     /**
      * Enables/Disables server info on error pages
      *
      * @param showServerInfo <code>true</code> to show server info
      */
     public void setShowServerInfo(boolean showServerInfo) {
         this.showServerInfo = showServerInfo;
     }

     public boolean isShowServerInfo() {
         return showServerInfo;
     }


     public boolean setProperty(String name, String value) {
         if (name.startsWith("errorCode.")) {
             int code = Integer.parseInt(name.substring(10));
             ErrorPage ep = new ErrorPage();
             ep.setErrorCode(code);
             ep.setLocation(value);
             errorPageSupport.add(ep);
             return true;
         } else if (name.startsWith("exceptionType.")) {
             String className = name.substring(14);
             ErrorPage ep = new ErrorPage();
             ep.setExceptionType(className);
             ep.setLocation(value);
             errorPageSupport.add(ep);
             return true;
         }
         return false;
     }

     public String getProperty(String name) {
         String result;
         if (name.startsWith("errorCode.")) {
             int code = Integer.parseInt(name.substring(10));
             ErrorPage ep = errorPageSupport.find(code);
             if (ep == null) {
                 result = null;
             } else {
                 result = ep.getLocation();
             }
         } else if (name.startsWith("exceptionType.")) {
             String className = name.substring(14);
             ErrorPage ep = errorPageSupport.find(className);
             if (ep == null) {
                 result = null;
             } else {
                 result = ep.getLocation();
             }
         } else {
             result = null;
         }
         return result;
     }
 }
	/*
	* 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.catalina.valves;

	import java.io.File;
	import java.io.FileInputStream;
	import java.io.IOException;
	import java.io.InputStream;
	import java.io.OutputStream;
	import java.io.Writer;
	import java.util.Scanner;
	import java.util.concurrent.atomic.AtomicBoolean;

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

	import org.apache.catalina.connector.Request;
	import org.apache.catalina.connector.Response;
	import org.apache.catalina.util.ErrorPageSupport;
	import org.apache.catalina.util.IOTools;
	import org.apache.catalina.util.ServerInfo;
	import org.apache.catalina.util.TomcatCSS;
	import org.apache.coyote.ActionCode;
	import org.apache.tomcat.util.ExceptionUtils;
	import org.apache.tomcat.util.descriptor.web.ErrorPage;
	import org.apache.tomcat.util.res.StringManager;
	import org.apache.tomcat.util.security.Escape;

	/**
	* <p>Implementation of a Valve that outputs HTML error pages.</p>
	*
	* <p>This Valve should be attached at the Host level, although it will work
	* if attached to a Context.</p>
	*
	* <p>HTML code from the Cocoon 2 project.</p>
	*
	* @author Remy Maucherat
	* @author Craig R. McClanahan
	* @author <a href="mailto:nicolaken@supereva.it">Nicola Ken Barozzi</a> Aisa
	* @author <a href="mailto:stefano@apache.org">Stefano Mazzocchi</a>
	* @author Yoav Shapira
	*/
	public class ErrorReportValve extends ValveBase {

	private boolean showReport = true;

	private boolean showServerInfo = true;

	private final ErrorPageSupport errorPageSupport = new ErrorPageSupport();


	//------------------------------------------------------ Constructor

	public ErrorReportValve() {
	super(true);
	}


	// --------------------------------------------------------- Public Methods

	/**
	* Invoke the next Valve in the sequence. When the invoke returns, check
	* the response state. If the status code is greater than or equal to 400
	* or an uncaught exception was thrown then the error handling will be
	* triggered.
	*
	* @param request The servlet request to be processed
	* @param response The servlet response to be created
	*
	* @exception IOException if an input/output error occurs
	* @exception ServletException if a servlet error occurs
	*/
	@Override
	public void invoke(Request request, Response response) throws IOException, ServletException {

	// Perform the request
	getNext().invoke(request, response);

	if (response.isCommitted()) {
	if (response.setErrorReported()) {
	// Error wasn't previously reported but we can't write an error
	// page because the response has already been committed. Attempt
	// to flush any data that is still to be written to the client.
	try {
	response.flushBuffer();
	} catch (Throwable t) {
	ExceptionUtils.handleThrowable(t);
	}
	// Close immediately to signal to the client that something went
	// wrong
	response.getCoyoteResponse().action(ActionCode.CLOSE_NOW,
	request.getAttribute(RequestDispatcher.ERROR_EXCEPTION));
	}
	return;
	}

	Throwable throwable = (Throwable) request.getAttribute(RequestDispatcher.ERROR_EXCEPTION);

	// If an async request is in progress and is not going to end once this
	// container thread finishes, do not process any error page here.
	if (request.isAsync() && !request.isAsyncCompleting()) {
	return;
	}

	if (throwable != null && !response.isError()) {
	// Make sure that the necessary methods have been called on the
	// response. (It is possible a component may just have set the
	// Throwable. Tomcat won't do that but other components might.)
	// These are safe to call at this point as we know that the response
	// has not been committed.
	response.reset();
	response.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
	}

	// One way or another, response.sendError() will have been called before
	// execution reaches this point and suspended the response. Need to
	// reverse that so this valve can write to the response.
	response.setSuspended(false);

	try {
	report(request, response, throwable);
	} catch (Throwable tt) {
	ExceptionUtils.handleThrowable(tt);
	}
	}


	// ------------------------------------------------------ Protected Methods


	/**
	* Prints out an error report.
	*
	* @param request The request being processed
	* @param response The response being generated
	* @param throwable The exception that occurred (which possibly wraps
	* a root cause exception
	*/
	protected void report(Request request, Response response, Throwable throwable) {

	int statusCode = response.getStatus();

	// Do nothing on a 1xx, 2xx and 3xx status
	// Do nothing if anything has been written already
	// Do nothing if the response hasn't been explicitly marked as in error
	// and that error has not been reported.
	if (statusCode < 400 \|\| response.getContentWritten() > 0 \|\| !response.setErrorReported()) {
	return;
	}

	// If an error has occurred that prevents further I/O, don't waste time
	// producing an error report that will never be read
	AtomicBoolean result = new AtomicBoolean(false);
	response.getCoyoteResponse().action(ActionCode.IS_IO_ALLOWED, result);
	if (!result.get()) {
	return;
	}

	ErrorPage errorPage = null;
	if (throwable != null) {
	errorPage = errorPageSupport.find(throwable);
	}
	if (errorPage == null) {
	errorPage = errorPageSupport.find(statusCode);
	}
	if (errorPage == null) {
	// Default error page
	errorPage = errorPageSupport.find(0);
	}


	if (errorPage != null) {
	if (sendErrorPage(errorPage.getLocation(), response)) {
	// If the page was sent successfully, don't write the standard
	// error page.
	return;
	}
	}

	String message = Escape.htmlElementContent(response.getMessage());
	if (message == null) {
	if (throwable != null) {
	String exceptionMessage = throwable.getMessage();
	if (exceptionMessage != null && exceptionMessage.length() > 0) {
	message = Escape.htmlElementContent((new Scanner(exceptionMessage)).nextLine());
	}
	}
	if (message == null) {
	message = "";
	}
	}

	// Do nothing if there is no reason phrase for the specified status code and
	// no error message provided
	String reason = null;
	String description = null;
	StringManager smClient = StringManager.getManager(
	Constants.Package, request.getLocales());
	response.setLocale(smClient.getLocale());
	try {
	reason = smClient.getString("http." + statusCode + ".reason");
	description = smClient.getString("http." + statusCode + ".desc");
	} catch (Throwable t) {
	ExceptionUtils.handleThrowable(t);
	}
	if (reason == null \|\| description == null) {
	if (message.isEmpty()) {
	return;
	} else {
	reason = smClient.getString("errorReportValve.unknownReason");
	description = smClient.getString("errorReportValve.noDescription");
	}
	}

	StringBuilder sb = new StringBuilder();

	sb.append("<!doctype html><html lang=\"");
	sb.append(smClient.getLocale().getLanguage()).append("\">");
	sb.append("<head>");
	sb.append("<title>");
	sb.append(smClient.getString("errorReportValve.statusHeader",
	String.valueOf(statusCode), reason));
	sb.append("</title>");
	sb.append("<style type=\"text/css\">");
	sb.append(TomcatCSS.TOMCAT_CSS);
	sb.append("</style>");
	sb.append("</head><body>");
	sb.append("<h1>");
	sb.append(smClient.getString("errorReportValve.statusHeader",
	String.valueOf(statusCode), reason)).append("</h1>");
	if (isShowReport()) {
	sb.append("<hr class=\"line\" />");
	sb.append("<p><b>");
	sb.append(smClient.getString("errorReportValve.type"));
	sb.append("</b> ");
	if (throwable != null) {
	sb.append(smClient.getString("errorReportValve.exceptionReport"));
	} else {
	sb.append(smClient.getString("errorReportValve.statusReport"));
	}
	sb.append("</p>");
	if (!message.isEmpty()) {
	sb.append("<p><b>");
	sb.append(smClient.getString("errorReportValve.message"));
	sb.append("</b> ");
	sb.append(message).append("</p>");
	}
	sb.append("<p><b>");
	sb.append(smClient.getString("errorReportValve.description"));
	sb.append("</b> ");
	sb.append(description);
	sb.append("</p>");
	if (throwable != null) {
	String stackTrace = getPartialServletStackTrace(throwable);
	sb.append("<p><b>");
	sb.append(smClient.getString("errorReportValve.exception"));
	sb.append("</b></p><pre>");
	sb.append(Escape.htmlElementContent(stackTrace));
	sb.append("</pre>");

	int loops = 0;
	Throwable rootCause = throwable.getCause();
	while (rootCause != null && (loops < 10)) {
	stackTrace = getPartialServletStackTrace(rootCause);
	sb.append("<p><b>");
	sb.append(smClient.getString("errorReportValve.rootCause"));
	sb.append("</b></p><pre>");
	sb.append(Escape.htmlElementContent(stackTrace));
	sb.append("</pre>");
	// In case root cause is somehow heavily nested
	rootCause = rootCause.getCause();
	loops++;
	}

	sb.append("<p><b>");
	sb.append(smClient.getString("errorReportValve.note"));
	sb.append("</b> ");
	sb.append(smClient.getString("errorReportValve.rootCauseInLogs"));
	sb.append("</p>");

	}
	sb.append("<hr class=\"line\" />");
	}
	if (isShowServerInfo()) {
	sb.append("<h3>").append(ServerInfo.getServerInfo()).append("</h3>");
	}
	sb.append("</body></html>");

	try {
	try {
	response.setContentType("text/html");
	response.setCharacterEncoding("utf-8");
	} catch (Throwable t) {
	ExceptionUtils.handleThrowable(t);
	if (container.getLogger().isDebugEnabled()) {
	container.getLogger().debug("status.setContentType", t);
	}
	}
	Writer writer = response.getReporter();
	if (writer != null) {
	// If writer is null, it's an indication that the response has
	// been hard committed already, which should never happen
	writer.write(sb.toString());
	response.finishResponse();
	}
	} catch (IOException e) {
	// Ignore
	} catch (IllegalStateException e) {
	// Ignore
	}

	}


	/**
	* Print out a partial servlet stack trace (truncating at the last
	* occurrence of javax.servlet.).
	* @param t The stack trace to process
	* @return the stack trace relative to the application layer
	*/
	protected String getPartialServletStackTrace(Throwable t) {
	StringBuilder trace = new StringBuilder();
	trace.append(t.toString()).append(System.lineSeparator());
	StackTraceElement[] elements = t.getStackTrace();
	int pos = elements.length;
	for (int i = elements.length - 1; i >= 0; i--) {
	if ((elements[i].getClassName().startsWith
	("org.apache.catalina.core.ApplicationFilterChain"))
	&& (elements[i].getMethodName().equals("internalDoFilter"))) {
	pos = i;
	break;
	}
	}
	for (int i = 0; i < pos; i++) {
	if (!(elements[i].getClassName().startsWith
	("org.apache.catalina.core."))) {
	trace.append('\t').append(elements[i].toString()).append(System.lineSeparator());
	}
	}
	return trace.toString();
	}


	private boolean sendErrorPage(String location, Response response) {
	File file = new File(location);
	if (!file.isAbsolute()) {
	file = new File(getContainer().getCatalinaBase(), location);
	}
	if (!file.isFile() \|\| !file.canRead()) {
	getContainer().getLogger().warn(
	sm.getString("errorReportValve.errorPageNotFound", location));
	return false;
	}

	// Hard coded for now. Consider making this optional. At Valve level or
	// page level?
	response.setContentType("text/html");
	response.setCharacterEncoding("UTF-8");

	try (OutputStream os = response.getOutputStream();
	InputStream is = new FileInputStream(file);){
	IOTools.flow(is, os);
	} catch (IOException e) {
	getContainer().getLogger().warn(
	sm.getString("errorReportValve.errorPageIOException", location), e);
	return false;
	}

	return true;
	}


	/**
	* Enables/Disables full error reports
	*
	* @param showReport <code>true</code> to show full error data
	*/
	public void setShowReport(boolean showReport) {
	this.showReport = showReport;
	}

	public boolean isShowReport() {
	return showReport;
	}

	/**
	* Enables/Disables server info on error pages
	*
	* @param showServerInfo <code>true</code> to show server info
	*/
	public void setShowServerInfo(boolean showServerInfo) {
	this.showServerInfo = showServerInfo;
	}

	public boolean isShowServerInfo() {
	return showServerInfo;
	}


	public boolean setProperty(String name, String value) {
	if (name.startsWith("errorCode.")) {
	int code = Integer.parseInt(name.substring(10));
	ErrorPage ep = new ErrorPage();
	ep.setErrorCode(code);
	ep.setLocation(value);
	errorPageSupport.add(ep);
	return true;
	} else if (name.startsWith("exceptionType.")) {
	String className = name.substring(14);
	ErrorPage ep = new ErrorPage();
	ep.setExceptionType(className);
	ep.setLocation(value);
	errorPageSupport.add(ep);
	return true;
	}
	return false;
	}

	public String getProperty(String name) {
	String result;
	if (name.startsWith("errorCode.")) {
	int code = Integer.parseInt(name.substring(10));
	ErrorPage ep = errorPageSupport.find(code);
	if (ep == null) {
	result = null;
	} else {
	result = ep.getLocation();
	}
	} else if (name.startsWith("exceptionType.")) {
	String className = name.substring(14);
	ErrorPage ep = errorPageSupport.find(className);
	if (ep == null) {
	result = null;
	} else {
	result = ep.getLocation();
	}
	} else {
	result = null;
	}
	return result;
	}
	}