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Struts example source code file (PrepareOperations.java)

This example Struts source code file (PrepareOperations.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 - Struts tags/keywords

actioncontext, actioncontext, actionmapping, actionmapping, dispatcher, http, httpservletrequest, httpservletresponse, integer, integer, ioexception, prepareoperations, regex, request, response, servlet, servletexception, string, string, util

The Struts PrepareOperations.java source code

/*
 * $Id: DefaultActionSupport.java 651946 2008-04-27 13:41:38Z apetrelli $
 *
 * 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.struts2.dispatcher.ng;

import org.apache.struts2.dispatcher.Dispatcher;
import org.apache.struts2.dispatcher.mapper.ActionMapping;
import org.apache.struts2.dispatcher.mapper.ActionMapper;
import org.apache.struts2.StrutsException;
import org.apache.struts2.RequestUtils;

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

import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.util.ValueStack;
import com.opensymphony.xwork2.util.ValueStackFactory;
import com.opensymphony.xwork2.util.logging.Logger;
import com.opensymphony.xwork2.util.logging.LoggerFactory;

import java.io.IOException;
import java.util.HashMap;
import java.util.List;
import java.util.regex.Pattern;

/**
 * Contains preparation operations for a request before execution
 */
public class PrepareOperations {

    private ServletContext servletContext;
    private Dispatcher dispatcher;
    private static final String STRUTS_ACTION_MAPPING_KEY = "struts.actionMapping";
    public static final String CLEANUP_RECURSION_COUNTER = "__cleanup_recursion_counter";
    private Logger log = LoggerFactory.getLogger(PrepareOperations.class);

    public PrepareOperations(ServletContext servletContext, Dispatcher dispatcher) {
        this.dispatcher = dispatcher;
        this.servletContext = servletContext;
    }

    /**
     * Creates the action context and initializes the thread local
     */
    public ActionContext createActionContext(HttpServletRequest request, HttpServletResponse response) {
        ActionContext ctx;
        Integer counter = 1;
        Integer oldCounter = (Integer) request.getAttribute(CLEANUP_RECURSION_COUNTER);
        if (oldCounter != null) {
            counter = oldCounter + 1;
        }
        
        ActionContext oldContext = ActionContext.getContext();
        if (oldContext != null) {
            // detected existing context, so we are probably in a forward
            ctx = new ActionContext(new HashMap<String, Object>(oldContext.getContextMap()));
        } else {
            ValueStack stack = dispatcher.getContainer().getInstance(ValueStackFactory.class).createValueStack();
            stack.getContext().putAll(dispatcher.createContextMap(request, response, null, servletContext));
            ctx = new ActionContext(stack.getContext());
        }
        request.setAttribute(CLEANUP_RECURSION_COUNTER, counter);
        ActionContext.setContext(ctx);
        return ctx;
    }

    /**
     * Cleans up a request of thread locals
     */
    public void cleanupRequest(HttpServletRequest request) {
        Integer counterVal = (Integer) request.getAttribute(CLEANUP_RECURSION_COUNTER);
        if (counterVal != null) {
            counterVal -= 1;
            request.setAttribute(CLEANUP_RECURSION_COUNTER, counterVal);
            if (counterVal > 0 ) {
                if (log.isDebugEnabled()) {
                    log.debug("skipping cleanup counter="+counterVal);
                }
                return;
            }
        }

        // always clean up the thread request, even if an action hasn't been executed
        ActionContext.setContext(null);
        Dispatcher.setInstance(null);
    }

    /**
     * Assigns the dispatcher to the dispatcher thread local
     */
    public void assignDispatcherToThread() {
        Dispatcher.setInstance(dispatcher);
    }

    /**
     * Sets the request encoding and locale on the response
     */
    public void setEncodingAndLocale(HttpServletRequest request, HttpServletResponse response) {
        dispatcher.prepare(request, response);
    }

    /**
     * Wraps the request with the Struts wrapper that handles multipart requests better
     * @return The new request, if there is one
     * @throws ServletException
     */
    public HttpServletRequest wrapRequest(HttpServletRequest oldRequest) throws ServletException {
        HttpServletRequest request = oldRequest;
        try {
            // Wrap request first, just in case it is multipart/form-data
            // parameters might not be accessible through before encoding (ww-1278)
            request = dispatcher.wrapRequest(request, servletContext);
        } catch (IOException e) {
            String message = "Could not wrap servlet request with MultipartRequestWrapper!";
            throw new ServletException(message, e);
        }
        return request;
    }

    /**
     *   Finds and optionally creates an {@link ActionMapping}.  It first looks in the current request to see if one
     * has already been found, otherwise, it creates it and stores it in the request.  No mapping will be created in the
     * case of static resource requests or unidentifiable requests for other servlets, for example.
     */
    public ActionMapping findActionMapping(HttpServletRequest request, HttpServletResponse response) {
        return findActionMapping(request, response, false);
    }

    /**
     * Finds and optionally creates an {@link ActionMapping}.  if forceLookup is false, it first looks in the current request to see if one
     * has already been found, otherwise, it creates it and stores it in the request.  No mapping will be created in the
     * case of static resource requests or unidentifiable requests for other servlets, for example.
     * @param forceLookup if true, the action mapping will be looked up from the ActionMapper instance, ignoring if there is one
     * in the request or not 
     */
    public ActionMapping findActionMapping(HttpServletRequest request, HttpServletResponse response, boolean forceLookup) {
        ActionMapping mapping = (ActionMapping) request.getAttribute(STRUTS_ACTION_MAPPING_KEY);
        if (mapping == null || forceLookup) {
            try {
                mapping = dispatcher.getContainer().getInstance(ActionMapper.class).getMapping(request, dispatcher.getConfigurationManager());
                if (mapping != null) {
                    request.setAttribute(STRUTS_ACTION_MAPPING_KEY, mapping);
                }
            } catch (Exception ex) {
                dispatcher.sendError(request, response, servletContext, HttpServletResponse.SC_INTERNAL_SERVER_ERROR, ex);
            }
        }

        return mapping;
    }

    /**
     * Cleans up the dispatcher instance
     */
    public void cleanupDispatcher() {
        if (dispatcher == null) {
            throw new StrutsException("something is seriously wrong, Dispatcher is not initialized (null) ");
        } else {
            try {
                dispatcher.cleanup();
            } finally {
                ActionContext.setContext(null);
            }
        }
    }

    /**
     * Check whether the request matches a list of exclude patterns.
     *
     * @param request          The request to check patterns against
     * @param excludedPatterns list of patterns for exclusion
     *
     * @return <tt>true if the request URI matches one of the given patterns
     */
    public boolean isUrlExcluded( HttpServletRequest request, List<Pattern> excludedPatterns ) {
        if (excludedPatterns != null) {
            String uri = getUri(request);
            for ( Pattern pattern : excludedPatterns ) {
                if (pattern.matcher(uri).matches()) {
                    return true;
                }
            }
        }
        return false;
    }

    /**
     * Gets the uri from the request
     *
     * @param request The request
     *
     * @return The uri
     */
    private String getUri( HttpServletRequest request ) {
        // handle http dispatcher includes.
        String uri = (String) request.getAttribute("javax.servlet.include.servlet_path");
        if (uri != null) {
            return uri;
        }

        uri = RequestUtils.getServletPath(request);
        if (uri != null && !"".equals(uri)) {
            return uri;
        }

        uri = request.getRequestURI();
        return uri.substring(request.getContextPath().length());
    }

}

Other Struts examples (source code examples)

Here is a short list of links related to this Struts PrepareOperations.java source code file:

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