com.dcs.controller.filter.SecurityServlet.java Source code

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Here is the source code for com.dcs.controller.filter.SecurityServlet.java

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/*
 * Copyright 1999-2011 Alibaba Group Holding Ltd.
 *
 * 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.dcs.controller.filter;

import java.io.IOException;
import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

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

public class SecurityServlet implements Filter {
    private Log logger = LogFactory.getLog(SecurityServlet.class);
    public static final String PARAM_NAME_EXCLUSIONS = "exclusions";
    private Set<String> excludesPattern;

    private String contextPath;

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
            throws IOException, ServletException {
        HttpServletRequest httpRequest = (HttpServletRequest) request;
        HttpServletResponse httpResponse = (HttpServletResponse) response;
        String requestURI = getRequestURI(httpRequest);
        logger.info(requestURI);
        if (isExclusion(requestURI)) {
            chain.doFilter(httpRequest, httpResponse);
            return;
        } else {
            HttpSession session = httpRequest.getSession();
            Object attribute = session.getAttribute("user");// 
            if (attribute == null && requestURI.indexOf("login") < 0) {
                httpRequest.setAttribute("message", "");
                httpResponse.sendRedirect(contextPath + "/login");
                return;
            }
            chain.doFilter(httpRequest, httpResponse);
        }
        return;
    }

    public boolean isExclusion(String requestURI) {
        if (excludesPattern == null) {
            return false;
        }

        if (contextPath != null && requestURI.startsWith(contextPath)) {
            requestURI = requestURI.substring(contextPath.length());
            if (!requestURI.startsWith("/")) {
                requestURI = "/" + requestURI;
            }
        }

        for (String pattern : excludesPattern) {
            if (matches(pattern, requestURI)) {
                return true;
            }
        }

        return false;
    }

    public String getRequestURI(HttpServletRequest request) {
        return request.getRequestURI();
    }

    @Override
    public void init(FilterConfig config) throws ServletException {
        {
            String exclusions = config.getInitParameter(PARAM_NAME_EXCLUSIONS);
            if (exclusions != null && exclusions.trim().length() != 0) {
                excludesPattern = new HashSet<String>(Arrays.asList(exclusions.split("\\s*,\\s*")));
            }
        }

        {

            this.contextPath = getContextPath(config.getServletContext());
        }
    }

    public static String getContextPath(ServletContext context) {
        if (context.getMajorVersion() == 2 && context.getMinorVersion() < 5) {
            return null;
        }

        try {
            return getContextPath_2_5(context);
        } catch (NoSuchMethodError error) {
            return null;
        }
    }

    private static String getContextPath_2_5(ServletContext context) {
        String contextPath = context.getContextPath();

        if (contextPath == null || contextPath.length() == 0) {
            contextPath = "/";
        }

        return contextPath;
    }

    @Override
    public void destroy() {
    }

    public String getContextPath() {
        return contextPath;
    }

    public boolean matches(String pattern, String source) {
        if (pattern == null || source == null) {
            return false;
        }
        pattern = pattern.trim();
        source = source.trim();
        if (pattern.endsWith("*")) {
            // pattern: /dcs* source:/dcs/index.html
            int length = pattern.length() - 1;
            if (source.length() >= length) {
                if (pattern.substring(0, length).equals(source.substring(0, length))) {
                    return true;
                }
            }
        } else if (pattern.startsWith("*")) {
            // pattern: *.html source:/xx/xx.html
            int length = pattern.length() - 1;
            if (source.length() >= length && source.endsWith(pattern.substring(1))) {
                return true;
            }
        } else {
            // pattern: /dcs/index.html source:/dcs/index.html
            if (pattern.equals(source)) {
                return true;
            }
        }
        return false;
    }
}