Java tutorial
/* * $Header: /home/cvs/jakarta-tomcat-catalina/catalina/src/share/org/apache/catalina/valves/ErrorReportValve.java,v 1.13 2004/01/01 23:53:46 markt Exp $ * $Revision: 1.13 $ * $Date: 2004/01/01 23:53:46 $ * * ==================================================================== * * The Apache Software License, Version 1.1 * * Copyright (c) 1999-2001 The Apache Software Foundation. All rights * reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * * 3. The end-user documentation included with the redistribution, if * any, must include the following acknowlegement: * "This product includes software developed by the * Apache Software Foundation (http://www.apache.org/)." * Alternately, this acknowlegement may appear in the software itself, * if and wherever such third-party acknowlegements normally appear. * * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software * Foundation" must not be used to endorse or promote products derived * from this software without prior written permission. For written * permission, please contact apache@apache.org. * * 5. Products derived from this software may not be called "Apache" * nor may "Apache" appear in their names without prior written * permission of the Apache Group. * * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * ==================================================================== * * This software consists of voluntary contributions made by many * individuals on behalf of the Apache Software Foundation. For more * information on the Apache Software Foundation, please see * <http://www.apache.org/>. * * [Additional notices, if required by prior licensing conditions] * */ package org.apache.catalina.valves; import java.io.IOException; import java.io.Writer; import java.util.Locale; import javax.servlet.ServletException; import javax.servlet.ServletRequest; import javax.servlet.ServletResponse; import javax.servlet.http.HttpServletResponse; import org.apache.catalina.Globals; import org.apache.catalina.HttpResponse; import org.apache.catalina.Logger; import org.apache.catalina.Request; import org.apache.catalina.Response; import org.apache.catalina.ValveContext; import org.apache.catalina.util.RequestUtil; import org.apache.catalina.util.ServerInfo; import org.apache.catalina.util.StringManager; import org.apache.commons.beanutils.PropertyUtils; import org.apache.tomcat.util.compat.JdkCompat; /** * <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> * @version $Revision: 1.13 $ $Date: 2004/01/01 23:53:46 $ */ public class ErrorReportValve extends ValveBase { // ----------------------------------------------------- Instance Variables /** * The debugging detail level for this component. */ private int debug = 0; /** * 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 * @param context The valve context used to invoke the next valve * in the current processing pipeline * * @exception IOException if an input/output error occurs * @exception ServletException if a servlet error occurs */ public void invoke(Request request, Response response, ValveContext context) throws IOException, ServletException { // Perform the request context.invokeNext(request, response); ServletRequest sreq = (ServletRequest) request; Throwable throwable = (Throwable) sreq.getAttribute(Globals.EXCEPTION_ATTR); ServletResponse sresp = (ServletResponse) response; if (sresp.isCommitted()) { return; } if (throwable != null) { // The response is an error response.setError(); // Reset the response (if possible) try { sresp.reset(); } catch (IllegalStateException e) { ; } ServletResponse sresponse = (ServletResponse) response; if (sresponse instanceof HttpServletResponse) ((HttpServletResponse) sresponse).sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR); } response.setSuspended(false); try { report(request, response, throwable); } catch (Throwable tt) { tt.printStackTrace(); } } /** * Return a String rendering of this object. */ public String toString() { StringBuffer sb = new StringBuffer("ErrorReportValve["); sb.append(container.getName()); sb.append("]"); return (sb.toString()); } // ------------------------------------------------------ Protected Methods /** * Prints out an error report. * * @param request The request being processed * @param response The response being generated * @param exception The exception that occurred (which possibly wraps * a root cause exception */ protected void report(Request request, Response response, Throwable throwable) throws IOException { // Do nothing on non-HTTP responses if (!(response instanceof HttpResponse)) return; HttpResponse hresponse = (HttpResponse) response; if (!(response instanceof HttpServletResponse)) return; HttpServletResponse hres = (HttpServletResponse) response; int statusCode = hresponse.getStatus(); // Do nothing on a 1xx, 2xx and 3xx status if (statusCode < 400) return; // FIXME: Reset part of the request /* try { if (hresponse.isError()) hresponse.reset(statusCode, message); } catch (IllegalStateException e) { ; } */ Throwable rootCause = null; if (throwable != null) { if (throwable instanceof ServletException) rootCause = ((ServletException) throwable).getRootCause(); } String message = RequestUtil.filter(hresponse.getMessage()); 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, message); } 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>"); 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 = JdkCompat.getJdkCompat().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>"); while (rootCause != null) { stackTrace = JdkCompat.getJdkCompat().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 try { rootCause = (Throwable) PropertyUtils.getProperty(rootCause, "rootCause"); } catch (ClassCastException e) { rootCause = null; } catch (IllegalAccessException e) { rootCause = null; } catch (NoSuchMethodException e) { rootCause = null; } catch (java.lang.reflect.InvocationTargetException e) { rootCause = null; } } sb.append("<p><b>"); sb.append(sm.getString("errorReportValve.note")); sb.append("</b> <u>"); sb.append(sm.getString("errorReportValve.rootCauseInLogs")); sb.append("</u></p>"); } sb.append("<HR size=\"1\" noshade>"); sb.append("<h3>").append(ServerInfo.getServerInfo()).append("</h3>"); sb.append("</body></html>"); try { Writer writer = response.getReporter(); if (writer != null) { Locale locale = Locale.getDefault(); try { hres.setContentType("text/html"); hres.setLocale(locale); } catch (Throwable t) { if (debug >= 1) log("status.setContentType", t); } // 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) { ; } } /** * Log a message on the Logger associated with our Container (if any). * * @param message Message to be logged */ protected void log(String message) { Logger logger = container.getLogger(); if (logger != null) logger.log(this.toString() + ": " + message); else System.out.println(this.toString() + ": " + message); } /** * Log a message on the Logger associated with our Container (if any). * * @param message Message to be logged * @param throwable Associated exception */ protected void log(String message, Throwable throwable) { Logger logger = container.getLogger(); if (logger != null) logger.log(this.toString() + ": " + message, throwable); else { System.out.println(this.toString() + ": " + message); throwable.printStackTrace(System.out); } } }