/*
* 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.IOException;
import java.io.Writer;
import java.util.Scanner;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletResponse;
import org.apache.catalina.Globals;
import org.apache.catalina.connector.Request;
import org.apache.catalina.connector.Response;
import org.apache.catalina.util.RequestUtil;
import org.apache.catalina.util.ServerInfo;
import org.apache.catalina.util.StringManager;
/**
* <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 {
// ----------------------------------------------------- Instance Variables
/**
* The descriptive information related to this implementation.
*/
private static final String info =
"org.apache.catalina.valves.ErrorReportValve/1.0";
/**
* The StringManager for this package.
*/
protected static StringManager sm =
StringManager.getManager(Constants.Package);
// ------------------------------------------------------------- Properties
/**
* Return descriptive information about this Valve implementation.
*/
public String getInfo() {
return (info);
}
// --------------------------------------------------------- Public Methods
/**
* Invoke the next Valve in the sequence. When the invoke returns, check
* the response state, and output an error report is necessary.
*
* @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
*/
public void invoke(Request request, Response response)
throws IOException, ServletException {
// Perform the request
getNext().invoke(request, response);
Throwable throwable =
(Throwable) request.getAttribute(Globals.EXCEPTION_ATTR);
if (response.isCommitted()) {
return;
}
if (throwable != null) {
// The response is an error
response.setError();
// Reset the response (if possible)
try {
response.reset();
} catch (IllegalStateException e) {
;
}
response.sendError
(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
}
response.setSuspended(false);
try {
report(request, response, throwable);
} catch (Throwable 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) {
// Do nothing on non-HTTP responses
int statusCode = response.getStatus();
// Do nothing on a 1xx, 2xx and 3xx status
// Do nothing if anything has been written already
if (statusCode < 400 || response.getContentCount() > 0 ||
!response.isError()) {
return;
}
String message = RequestUtil.filter(response.getMessage());
if (message == null) {
if (throwable != null) {
String exceptionMessage = throwable.getMessage();
if (exceptionMessage != null && exceptionMessage.length() > 0) {
message = RequestUtil.filter(
(new Scanner(exceptionMessage)).nextLine());
}
}
if (message == null) {
message = "";
}
}
// Do nothing if there is no report for the specified status code
String report = null;
try {
report = sm.getString("http." + statusCode);
} catch (Throwable t) {
;
}
if (report == null)
return;
StringBuffer sb = new StringBuffer();
sb.append("<html><head><title>");
sb.append(ServerInfo.getServerInfo()).append(" - ");
sb.append(sm.getString("errorReportValve.errorReport"));
sb.append("</title>");
sb.append("<style><!--");
sb.append(org.apache.catalina.util.TomcatCSS.TOMCAT_CSS);
sb.append("--></style> ");
sb.append("</head><body>");
sb.append("<h1>");
sb.append(sm.getString("errorReportValve.statusHeader",
"" + statusCode, message)).append("</h1>");
sb.append("<HR size=\"1\" noshade=\"noshade\">");
sb.append("<p><b>type</b> ");
if (throwable != null) {
sb.append(sm.getString("errorReportValve.exceptionReport"));
} else {
sb.append(sm.getString("errorReportValve.statusReport"));
}
sb.append("</p>");
sb.append("<p><b>");
sb.append(sm.getString("errorReportValve.message"));
sb.append("</b> <u>");
sb.append(message).append("</u></p>");
sb.append("<p><b>");
sb.append(sm.getString("errorReportValve.description"));
sb.append("</b> <u>");
sb.append(report);
sb.append("</u></p>");
if (throwable != null) {
String stackTrace = getPartialServletStackTrace(throwable);
sb.append("<p><b>");
sb.append(sm.getString("errorReportValve.exception"));
sb.append("</b> <pre>");
sb.append(RequestUtil.filter(stackTrace));
sb.append("</pre></p>");
int loops = 0;
Throwable rootCause = throwable.getCause();
while (rootCause != null && (loops < 10)) {
stackTrace = getPartialServletStackTrace(rootCause);
sb.append("<p><b>");
sb.append(sm.getString("errorReportValve.rootCause"));
sb.append("</b> <pre>");
sb.append(RequestUtil.filter(stackTrace));
sb.append("</pre></p>");
// In case root cause is somehow heavily nested
rootCause = rootCause.getCause();
loops++;
}
sb.append("<p><b>");
sb.append(sm.getString("errorReportValve.note"));
sb.append("</b> <u>");
sb.append(sm.getString("errorReportValve.rootCauseInLogs",
ServerInfo.getServerInfo()));
sb.append("</u></p>");
}
sb.append("<HR size=\"1\" noshade=\"noshade\">");
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) {
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());
}
} catch (IOException e) {
;
} catch (IllegalStateException e) {
;
}
}
/**
* Print out a partial servlet stack trace (truncating at the last
* occurrence of javax.servlet.).
*/
protected String getPartialServletStackTrace(Throwable t) {
StringBuffer trace = new StringBuffer();
trace.append(t.toString()).append('\n');
StackTraceElement[] elements = t.getStackTrace();
int pos = elements.length;
for (int i = 0; i < elements.length; i++) {
if ((elements[i].getClassName().startsWith
("org.apache.catalina.core.ApplicationFilterChain"))
&& (elements[i].getMethodName().equals("internalDoFilter"))) {
pos = i;
}
}
for (int i = 0; i < pos; i++) {
if (!(elements[i].getClassName().startsWith
("org.apache.catalina.core."))) {
trace.append('\t').append(elements[i].toString()).append('\n');
}
}
return trace.toString();
}
}