edu.rosehulman.sws.extension.AbstractPlugin.java Source code

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Here is the source code for edu.rosehulman.sws.extension.AbstractPlugin.java

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/*
 * AbstractPlugin.java
 * Apr 30, 2015
 *
 * Simple Web Server (SWS) for EE407/507 and CS455/555
 * 
 * Copyright (C) 2011 Chandan Raj Rupakheti, Clarkson University
 * 
 * This program is free software: you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public License 
 * as published by the Free Software Foundation, either 
 * version 3 of the License, or any later version.
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/lgpl.html>.
 * 
 * Contact Us:
 * Chandan Raj Rupakheti (rupakhcr@clarkson.edu)
 * Department of Electrical and Computer Engineering
 * Clarkson University
 * Potsdam
 * NY 13699-5722
 * http://clarkson.edu/~rupakhcr
 */

package edu.rosehulman.sws.extension;

import java.io.BufferedReader;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.lang.reflect.Constructor;
import java.net.URL;
import java.net.URLClassLoader;
import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.apache.commons.lang3.StringUtils;

import edu.rosehulman.sws.impl.HTTPResponses.Response200OK;
import edu.rosehulman.sws.protocol.IHttpRequest;
import edu.rosehulman.sws.protocol.IHttpResponse;
import edu.rosehulman.sws.server.Server;
import edu.rosehulman.sws.server.URLParser;

/**
 * 
 * @author Chandan R. Rupakheti (rupakhcr@clarkson.edu)
 */
public abstract class AbstractPlugin implements IPlugin {

    protected String domain = ""; //This will be some constant in all concrete plugin implementations
    protected Map<String, IServlet> servletMap;
    protected String servletDir;
    protected Map<String, User> users;

    public AbstractPlugin() {
        users = new HashMap<String, User>();
        loadServlets("servlets");
    }

    public Map<String, User> getUsers() {
        return users;
    }

    public static String getServeltRouteKey(String method, String uri) {
        return (method + uri).toLowerCase();
    }

    public void loadServlets(String servletDir) {
        this.servletDir = servletDir;
        System.out.println("LOAD SERVLETS");

        // lookup route file for specific plugin domain
        InputStream in = getClass().getResourceAsStream(File.separator + IPlugin.ROUTE_FILE_NAME);
        this.servletMap = new HashMap<String, IServlet>();

        try {
            // load each line entry of route file into map
            BufferedReader br = new BufferedReader(new InputStreamReader(in));
            String line = null;
            while ((line = br.readLine()) != null) {
                //System.out.println("ROUTE LOADED: " + line);
                parseRouteLine(line);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }

        for (String s : this.servletMap.keySet()) {
            //System.out.println("KEY: " + s + " - " + servletMap.get(s).getClass().toString());
        }
    }

    private void parseRouteLine(String line) {
        // split line on any amount of white space in between parts
        String[] routeParts = line.split("\\s+");
        String path = routeParts[0].replaceAll(".*[/\\\\].*", File.separator);
        String routeKey = getServeltRouteKey(path, routeParts[1]);
        String routeServletClass = routeParts[2];

        // create new servlet instance frome routeServlet name
        Class<?> servletClass;
        try {
            URL location = getClass().getProtectionDomain().getCodeSource().getLocation();
            ClassLoader classLoader = new URLClassLoader(
                    new URL[] { new File(location.getFile()).toURI().toURL() });
            servletClass = classLoader.loadClass(routeServletClass);
            Constructor<?> servletConstructor = servletClass.getConstructor();
            Object servletObj = servletConstructor.newInstance();
            IServlet servlet = (IServlet) servletObj;
            servlet.setPlugin(this);
            this.servletMap.put(routeKey, servlet);
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

    public String getDomain() {
        return domain;
    }

    public IPlugin getPlugin() {
        return this;
    }

    public void route(IHttpRequest request, IHttpResponse response) {
        String servletName = URLParser.getServletDomain(request.getUri());
        String servletMapKey = getServeltRouteKey(request.getMethod(), servletName);
        IServlet s = findServlet(servletMapKey);

        if (s != null) {
            //System.out.println("FOUND SERVLET = " + servletMapKey);
            s.process(request, new Response200OK());
        } else {
            //System.out.println("SERVLET NOT FOUND!!! - "+ servletMapKey);
            //System.out.println("LOOKING FOR static resource");
            request.handleRequest();
        }
    }

    private IServlet findServlet(String servletKey) {
        List<String> keyParts = Arrays.asList(servletKey.split("/"));
        IServlet servlet = null;
        for (int i = keyParts.size(); i > 0; i--) {
            String key = StringUtils.join(keyParts.subList(0, i), "/");
            //System.out.println("KEY CHECK: " + key);
            servlet = this.servletMap.get(key);
            if (servlet != null)
                break;
        }
        return servlet;
    }

}