Glassfish example source code file (InvokerServlet.java)

This example Glassfish source code file (InvokerServlet.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Glassfish tags/keywords

context, http, httpservletresponse, invokerhttprequest, io, ioexception, ioexception, request, response, runtimeexception, servlet, servletexception, servletexception, string, string, throwable, throwable, unavailableexception, wrapper

The Glassfish InvokerServlet.java source code

/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright (c) 1997-2010 Oracle and/or its affiliates. All rights reserved.
 *
 * The contents of this file are subject to the terms of either the GNU
 * General Public License Version 2 only ("GPL") or the Common Development
 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License.  You can
 * obtain a copy of the License at
 * https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html
 * or packager/legal/LICENSE.txt.  See the License for the specific
 * language governing permissions and limitations under the License.
 *
 * When distributing the software, include this License Header Notice in each
 * file and include the License file at packager/legal/LICENSE.txt.
 *
 * GPL Classpath Exception:
 * Oracle designates this particular file as subject to the "Classpath"
 * exception as provided by Oracle in the GPL Version 2 section of the License
 * file that accompanied this code.
 *
 * Modifications:
 * If applicable, add the following below the License Header, with the fields
 * enclosed by brackets [] replaced by your own identifying information:
 * "Portions Copyright [year] [name of copyright owner]"
 *
 * Contributor(s):
 * If you wish your version of this file to be governed by only the CDDL or
 * only the GPL Version 2, indicate your decision by adding "[Contributor]
 * elects to include this software in this distribution under the [CDDL or GPL
 * Version 2] license."  If you don't indicate a single choice of license, a
 * recipient has the option to distribute your version of this file under
 * either the CDDL, the GPL Version 2 or to extend the choice of license to
 * its licensees as provided above.  However, if you add GPL Version 2 code
 * and therefore, elected the GPL Version 2 license, then the option applies
 * only if the new code is made subject to such option by the copyright
 * holder.
 *
 *
 * This file incorporates work covered by the following copyright and
 * permission notice:
 *
 * Copyright 2004 The Apache Software Foundation
 *
 * Licensed 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.servlets;


import org.apache.catalina.ContainerServlet;
import org.apache.catalina.Context;
import org.apache.catalina.Globals;
import org.apache.catalina.Wrapper;
import org.apache.catalina.util.StringManager;

import javax.servlet.RequestDispatcher;
import javax.servlet.Servlet;
import javax.servlet.ServletException;
import javax.servlet.UnavailableException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;


/**
 * The default servlet-invoking servlet for most web applications,
 * used to serve requests to servlets that have not been registered
 * in the web application deployment descriptor.
 *
 * @author Craig R. McClanahan
 * @version $Revision: 1.3 $ $Date: 2005/12/08 01:27:56 $
 */

public final class InvokerServlet
    extends HttpServlet implements ContainerServlet {


    // ----------------------------------------------------- Instance Variables


    /**
     * The Context container associated with our web application.
     */
    private Context context = null;


    /**
     * The debugging detail level for this servlet.
     */
    private int debug = 0;


    /**
     * The string manager for this package.
     */
    private static StringManager sm =
        StringManager.getManager(Constants.Package);


    /**
     * The Wrapper container associated with this servlet.
     */
    private Wrapper wrapper = null;


    // ----------------------------------------------- ContainerServlet Methods


    /**
     * Return the Wrapper with which we are associated.
     */
    public synchronized Wrapper getWrapper() {

        return (this.wrapper);

    }


    /**
     * Set the Wrapper with which we are associated.
     *
     * @param wrapper The new wrapper
     */
    public synchronized void setWrapper(Wrapper wrapper) {
        this.wrapper = wrapper;
        if (wrapper == null)
            context = null;
        else
            context = (Context) wrapper.getParent();
    }


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


    /**
     * Finalize this servlet.
     */
    public void destroy() {

        ;       // No actions necessary

    }


    /**
     * Process a GET request for the specified resource.
     *
     * @param request The servlet request we are processing
     * @param response The servlet response we are creating
     *
     * @exception IOException if an input/output error occurs
     * @exception ServletException if a servlet-specified error occurs
     */
    public void doGet(HttpServletRequest request,
                      HttpServletResponse response)
        throws IOException, ServletException {

        serveRequest(request, response);

    }


    /**
     * Process a HEAD request for the specified resource.
     *
     * @param request The servlet request we are processing
     * @param response The servlet response we are creating
     *
     * @exception IOException if an input/output error occurs
     * @exception ServletException if a servlet-specified error occurs
     */
    public void doHead(HttpServletRequest request,
                       HttpServletResponse response)
        throws IOException, ServletException {

        serveRequest(request, response);

    }


    /**
     * Process a POST request for the specified resource.
     *
     * @param request The servlet request we are processing
     * @param response The servlet response we are creating
     *
     * @exception IOException if an input/output error occurs
     * @exception ServletException if a servlet-specified error occurs
     */
    public void doPost(HttpServletRequest request,
                       HttpServletResponse response)
        throws IOException, ServletException {

        serveRequest(request, response);

    }


    /**
     * Initialize this servlet.
     */
    public synchronized void init() throws ServletException {

        // Ensure that our ContainerServlet properties have been set
        if ((wrapper == null) || (context == null))
            throw new UnavailableException
                (sm.getString("invokerServlet.noWrapper"));

        // Set our properties from the initialization parameters
        String value = null;
        try {
            value = getServletConfig().getInitParameter("debug");
            debug = Integer.parseInt(value);
        } catch (Throwable t) {
            ;
        }
        if (debug >= 1)
            log("init: Associated with Context '" + context.getPath() + "'");

    }



    // -------------------------------------------------------- Private Methods


    /**
     * Serve the specified request, creating the corresponding response.
     * After the first time a particular servlet class is requested, it will
     * be served directly (like any registered servlet) because it will have
     * been registered and mapped in our associated Context.
     *
     * <p>Synchronize to avoid race conditions when multiple requests
     * try to initialize the same servlet at the same time
     *
     * @param request The servlet request we are processing
     * @param response The servlet response we are creating
     *
     * @exception IOException if an input/output error occurs
     * @exception ServletException if a servlet-specified error occurs
     */
    public synchronized void serveRequest(HttpServletRequest request,
            HttpServletResponse response)
        throws IOException, ServletException {

        // Disallow calling this servlet via a named dispatcher
        if (request.getAttribute(Globals.NAMED_DISPATCHER_ATTR) != null)
            throw new ServletException
                (sm.getString("invokerServlet.notNamed"));

        // Identify the input parameters and our "included" state
        String inRequestURI = null;
        String inServletPath = null;
        String inPathInfo = null;
        boolean included =
            (request.getAttribute(RequestDispatcher.INCLUDE_REQUEST_URI) != null);

        if (included) {
            inRequestURI = (String) request.getAttribute(
                RequestDispatcher.INCLUDE_REQUEST_URI);
            inServletPath = (String) request.getAttribute(
                RequestDispatcher.INCLUDE_SERVLET_PATH);
            inPathInfo = (String) request.getAttribute(
                RequestDispatcher.INCLUDE_PATH_INFO);
        } else {
            inRequestURI = request.getRequestURI();
            inServletPath = request.getServletPath();
            inPathInfo = request.getPathInfo();
        }
        if (debug >= 1) {
            log("included='" + included + "', requestURI='" +
                inRequestURI + "'");
            log("  servletPath='" + inServletPath + "', pathInfo='" +
                inPathInfo + "'");
        }

        // Make sure a servlet name or class name was specified
        if (inPathInfo == null) {
            if (debug >= 1)
                log("Invalid pathInfo '" + inPathInfo + "'");
            if (included)
                throw new ServletException
                    (sm.getString("invokerServlet.invalidPath", inRequestURI));
            else {
                /* IASRI 4878272
                response.sendError(HttpServletResponse.SC_NOT_FOUND,
                                   inRequestURI);
                */
                // BEGIN IASRI 4878272
                log(sm.getString("invokerServlet.invalidPath", inRequestURI));
                response.sendError(HttpServletResponse.SC_NOT_FOUND);
                // END IASRI 4878272
                return;
            }
        }

        // Identify the outgoing servlet name or class, and outgoing path info
        String pathInfo = inPathInfo;
        String servletClass = pathInfo.substring(1);
        int slash = servletClass.indexOf('/');
        //        if (debug >= 2)
        //            log("  Calculating with servletClass='" + servletClass +
        //                "', pathInfo='" + pathInfo + "', slash=" + slash);
        if (slash >= 0) {
            pathInfo = servletClass.substring(slash);
            servletClass = servletClass.substring(0, slash);
        } else {
            pathInfo = "";
        }

        if (servletClass.startsWith("org.apache.catalina")) {
            /* IASRI 4878272
            response.sendError(HttpServletResponse.SC_NOT_FOUND,
                               inRequestURI);
            */
            // BEGIN IASRI 4878272
            response.sendError(HttpServletResponse.SC_NOT_FOUND);
            // END IASRI 4878272
            return;
        }

        if (debug >= 1)
            log("Processing servlet '" + servletClass +
                "' with path info '" + pathInfo + "'");
        String name = "org.apache.catalina.INVOKER." + servletClass;
        String pattern = inServletPath + "/" + servletClass + "/*";
        Wrapper wrapper = null;

        // Are we referencing an existing servlet class or name?
        wrapper = (Wrapper) context.findChild(servletClass);
        if (wrapper == null)
            wrapper = (Wrapper) context.findChild(name);
        if (wrapper != null) {
            String actualServletClass = wrapper.getServletClassName();
            if ((actualServletClass != null)
                && (actualServletClass.startsWith
                    ("org.apache.catalina"))) {
                /* IASRI 4878272
                response.sendError(HttpServletResponse.SC_NOT_FOUND,
                                   inRequestURI);
                */
                // BEGIN IASRI 4878272
                response.sendError(HttpServletResponse.SC_NOT_FOUND);
                // END IASRI 4878272
                return;
            }
            if (debug >= 1)
                log("Using wrapper for servlet '" +
                    wrapper.getName() + "' with mapping '" +
                    pattern + "'");
            context.addServletMapping(pattern, wrapper.getName());
        }

        // No, create a new wrapper for the specified servlet class
        else {
            if (debug >= 1)
                log("Creating wrapper for '" + servletClass +
                    "' with mapping '" + pattern + "'");
            try {
                wrapper = context.createWrapper();
                wrapper.setName(name);
                wrapper.setLoadOnStartup(1);
                wrapper.setServletClassName(servletClass);
                context.addChild(wrapper);
                context.addServletMapping(pattern, name);
            } catch (Throwable t) {
                log(sm.getString("invokerServlet.cannotCreate",
                                 inRequestURI), t);
                context.removeServletMapping(pattern);
                context.removeChild(wrapper);
                if (included)
                    throw new ServletException
                        (sm.getString("invokerServlet.cannotCreate",
                                      inRequestURI), t);
                else {
                    /* IASRI 4878272
                    response.sendError(HttpServletResponse.SC_NOT_FOUND,
                                       inRequestURI);
                    */
                    // BEGIN IASRI 4878272
                    log(sm.getString("invokerServlet.invalidPath", 
                                     inRequestURI));
                    response.sendError(HttpServletResponse.SC_NOT_FOUND);
                    // END IASRI 4878272
                    return;
                }
            }
        }

        // Create a request wrapper to pass on to the invoked servlet
        InvokerHttpRequest wrequest =
            new InvokerHttpRequest(request);
        wrequest.setRequestURI(inRequestURI);
        StringBuilder sb = new StringBuilder(inServletPath);
        sb.append("/");
        sb.append(servletClass);
        wrequest.setServletPath(sb.toString());
        if ((pathInfo == null) || (pathInfo.length() < 1)) {
            wrequest.setPathInfo(null);
            wrequest.setPathTranslated(null);
        } else {
            wrequest.setPathInfo(pathInfo);
            wrequest.setPathTranslated
                (getServletContext().getRealPath(pathInfo));
        }

        // Allocate a servlet instance to perform this request
        Servlet instance = null;
        try {
            //            if (debug >= 2)
            //                log("  Allocating servlet instance");
            instance = wrapper.allocate();
        } catch (ServletException e) {
            log(sm.getString("invokerServlet.allocate", inRequestURI), e);
            context.removeServletMapping(pattern);
            context.removeChild(wrapper);
            Throwable rootCause = e.getRootCause();
            if (rootCause == null)
                rootCause = e;
            if (rootCause instanceof ClassNotFoundException) {
                /* IASRI 4878272
                response.sendError(HttpServletResponse.SC_NOT_FOUND,
                                   inRequestURI);
                */
                // BEGIN IASRI 4878272
                log(sm.getString("invokerServlet.invalidPath", inRequestURI));
                response.sendError(HttpServletResponse.SC_NOT_FOUND);
                // END IASRI 4878272
                return;
            } else if (rootCause instanceof IOException) {
                throw (IOException) rootCause;
            } else if (rootCause instanceof RuntimeException) {
                throw (RuntimeException) rootCause;
            } else if (rootCause instanceof ServletException) {
                throw (ServletException) rootCause;
            } else {
                throw new ServletException
                    (sm.getString("invokerServlet.allocate", inRequestURI),
                     rootCause);
            }
        } catch (Throwable e) {
            log(sm.getString("invokerServlet.allocate", inRequestURI), e);
            context.removeServletMapping(pattern);
            context.removeChild(wrapper);
            throw new ServletException
                (sm.getString("invokerServlet.allocate", inRequestURI), e);
        }

        // After loading the wrapper, restore some of the fields when including
        if (included) {
            wrequest.setRequestURI(request.getRequestURI());
            wrequest.setPathInfo(request.getPathInfo());
            wrequest.setServletPath(request.getServletPath());
        }

        // Invoke the service() method of the allocated servlet
        try {
            String jspFile = wrapper.getJspFile();
            if (jspFile != null)
                request.setAttribute(Globals.JSP_FILE_ATTR, jspFile);
            else
                request.removeAttribute(Globals.JSP_FILE_ATTR);
            request.setAttribute(Globals.INVOKED_ATTR,
                                 request.getServletPath());
            //            if (debug >= 2)
            //                log("  Calling service() method, jspFile=" +
            //                    jspFile);
            instance.service(wrequest, response);
            request.removeAttribute(Globals.INVOKED_ATTR);
            request.removeAttribute(Globals.JSP_FILE_ATTR);
        } catch (IOException e) {
            //            if (debug >= 2)
            //                log("  service() method IOException", e);
            request.removeAttribute(Globals.INVOKED_ATTR);
            request.removeAttribute(Globals.JSP_FILE_ATTR);
            try {
                wrapper.deallocate(instance);
            } catch (Throwable f) {
                ;
            }
            throw e;
        } catch (UnavailableException e) {
            //            if (debug >= 2)
            //                log("  service() method UnavailableException", e);
            context.removeServletMapping(pattern);
            request.removeAttribute(Globals.INVOKED_ATTR);
            request.removeAttribute(Globals.JSP_FILE_ATTR);
            try {
                wrapper.deallocate(instance);
            } catch (Throwable f) {
                ;
            }
            throw e;
        } catch (ServletException e) {
            //            if (debug >= 2)
            //                log("  service() method ServletException", e);
            request.removeAttribute(Globals.INVOKED_ATTR);
            request.removeAttribute(Globals.JSP_FILE_ATTR);
            try {
                wrapper.deallocate(instance);
            } catch (Throwable f) {
                ;
            }
            throw e;
        } catch (RuntimeException e) {
            //            if (debug >= 2)
            //                log("  service() method RuntimeException", e);
            request.removeAttribute(Globals.INVOKED_ATTR);
            request.removeAttribute(Globals.JSP_FILE_ATTR);
            try {
                wrapper.deallocate(instance);
            } catch (Throwable f) {
                ;
            }
            throw e;
        } catch (Throwable e) {
            //            if (debug >= 2)
            //                log("  service() method Throwable", e);
            request.removeAttribute(Globals.INVOKED_ATTR);
            request.removeAttribute(Globals.JSP_FILE_ATTR);
            try {
                wrapper.deallocate(instance);
            } catch (Throwable f) {
                ;
            }
            throw new ServletException("Invoker service() exception", e);
        }

        // Deallocate the allocated servlet instance
        try {
            //            if (debug >= 2)
            //                log("  deallocate servlet instance");
            wrapper.deallocate(instance);
        } catch (ServletException e) {
            log(sm.getString("invokerServlet.deallocate", inRequestURI), e);
            throw e;
        } catch (Throwable e) {
            log(sm.getString("invokerServlet.deallocate", inRequestURI), e);
            throw new ServletException
                (sm.getString("invokerServlet.deallocate", inRequestURI), e);
        }

    }


}