com.mnt.base.web.servlets.AccessRouterServlet.java Source code

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Here is the source code for com.mnt.base.web.servlets.AccessRouterServlet.java

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/**
 * $Revision: 1.0
 * $Date: 2013-5-21
 *
 * Copyright (C) 2013-2020 MNT. All rights reserved.
 *
 * 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 com.mnt.base.web.servlets;

import java.io.IOException;
import java.util.LinkedHashMap;
import java.util.Map;

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

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import com.mnt.base.json.JSONTool;
import com.mnt.base.util.BaseConfiguration;
import com.mnt.base.util.BeanContext;
import com.mnt.base.util.CommonUtil;
import com.mnt.base.util.HttpUtil;
import com.mnt.base.web.WebUtils;
import com.mnt.base.web.action.ActionControllerManager;
import com.mnt.base.web.action.InvalidPostHandler;
import com.mnt.base.web.action.ResponseHandler;

/**
 * Handle request and dispatch the process to action handler manager. 
 * 
 * @author Peng Peng
 * #date 2012-3-22
 *
 *
 */
public class AccessRouterServlet extends HttpServlet {

    private static final long serialVersionUID = -855582088339247085L;

    private final Log log = LogFactory.getLog(getClass());

    private ActionControllerManager actionControllerManager;

    private static final String HTTP_GET = "get";
    private static final String HTTP_DELETE = "delete";
    private static final String HTTP_HEAD = "head";

    public AccessRouterServlet() {
        BeanContext beanContext = BeanContext.getInstance();
        actionControllerManager = beanContext.getBean("actionControllerManager", ActionControllerManager.class);
    }

    @SuppressWarnings("unchecked")
    @Override
    protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        WebUtils.setupContext(req, resp);

        if (!WebUtils.checkAuth(req, resp)) {
            return;
        }

        String reqMethod = req.getMethod();
        String requestUri = req.getRequestURI();
        Map<String, Object> parameterMap = null;

        String contentType = req.getHeader("content-type");

        if (HTTP_GET.equalsIgnoreCase(reqMethod) || HTTP_DELETE.equalsIgnoreCase(reqMethod)
                || HTTP_HEAD.equalsIgnoreCase(reqMethod) || !"application/json".equalsIgnoreCase(contentType)) {
            parameterMap = new LinkedHashMap<String, Object>();
            parameterMap.putAll(req.getParameterMap());
        } else {
            String requestContent = null;
            try {
                requestContent = HttpUtil.readData(req.getInputStream());
            } catch (IOException e) {
                log.error("Fail to read the http request content. SKIP the request.", e);
                resp.getOutputStream().close();
                return;
            }

            if (!CommonUtil.isEmpty(requestContent)) {
                try {
                    parameterMap = (Map<String, Object>) JSONTool.convertJsonToObject(requestContent);
                } catch (Exception e) {
                    if (log.isDebugEnabled()) {
                        log.debug("Fail to convert the json string to parameter map. SKIP the request: "
                                + requestContent, e);
                    }

                    InvalidPostHandler invalidPostHandler = null;

                    try {
                        invalidPostHandler = BeanContext.getInstance().getBean("invalidPostHandler",
                                InvalidPostHandler.class);
                    } catch (Exception skipe) {
                        // skip it
                    }

                    if (invalidPostHandler != null) {
                        try {
                            invalidPostHandler.handle(req, resp, requestContent);
                        } catch (Exception e1) {
                            log.error("error while handle invalid post request.", e);
                        }
                    } else {
                        resp.getOutputStream().close();
                    }
                    return;
                }
            } else {
                parameterMap = new LinkedHashMap<String, Object>();
            }
        }

        actionControllerManager.dispatchRequest(requestUri, req.getMethod(), parameterMap,
                new HTMLResponseHandler(resp, BaseConfiguration.getResponseContentType()));
        CommonUtil.deepClear(parameterMap);

        WebUtils.clearContext();
    }

    //private Object syncObj = new Object();

    private class HTMLResponseHandler implements ResponseHandler {

        private HttpServletResponse response;
        protected String contentType;

        public HTMLResponseHandler(HttpServletResponse response, String contentType) {
            this.response = response;
            this.contentType = contentType;
        }

        public void setContentType(String contentType) {
            this.contentType = contentType;
        }

        public void response(Object o) {
            response(response, o.toString(), this.contentType == null ? "text/html" : this.contentType);
        }

        public void response(HttpServletResponse response, String contentData, String contentType) {
            synchronized (response) {
                response.setContentType(contentType);
                response.setHeader("Expires", "0");
                response.setHeader("Cache-Control", "no-cache");
                response.setHeader("Pragma", "no-cache");

                try {
                    response.getWriter().print(contentData);
                    response.getWriter().flush();
                } catch (IOException e) {
                    log.error("fail to output response to client.", e);
                }
            }
        }
    }
}