Quadcap Embeddable Server

com/quadcap/http/server22/WebApplication.java

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package com.quadcap.http.server22;

/* Copyright 1997 - 2003 Quadcap Software.  All rights reserved.
 *
 * This software is distributed under the Quadcap Free Software License.
 * This software may be used or modified for any purpose, personal or
 * commercial.  Open Source redistributions are permitted.  Commercial
 * redistribution of larger works derived from, or works which bundle
 * this software requires a "Commercial Redistribution License"; see
 * http://www.quadcap.com/purchase.
 *
 * Redistributions qualify as "Open Source" under  one of the following terms:
 *   
 *    Redistributions are made at no charge beyond the reasonable cost of
 *    materials and delivery.
 *
 *    Redistributions are accompanied by a copy of the Source Code or by an
 *    irrevocable offer to provide a copy of the Source Code for up to three
 *    years at the cost of materials and delivery.  Such redistributions
 *    must allow further use, modification, and redistribution of the Source
 *    Code under substantially the same terms as this license.
 *
 * Redistributions of source code must retain the copyright notices as they
 * appear in each source code file, these license terms, and the
 * disclaimer/limitation of liability set forth as paragraph 6 below.
 *
 * Redistributions in binary form must reproduce this Copyright Notice,
 * these license terms, and the disclaimer/limitation of liability set
 * forth as paragraph 6 below, in the documentation and/or other materials
 * provided with the distribution.
 *
 * The Software is provided on an "AS IS" basis.  No warranty is
 * provided that the Software is free of defects, or fit for a
 * particular purpose.  
 *
 * Limitation of Liability. Quadcap Software shall not be liable
 * for any damages suffered by the Licensee or any third party resulting
 * from use of the Software.
 */

import java.io.File;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.IOException;
import java.io.Reader;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Hashtable;
import java.util.List;
import java.util.Properties;
import java.util.Vector;

import java.net.URL;
import java.net.MalformedURLException;

import javax.servlet.RequestDispatcher;
import javax.servlet.Servlet;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;

import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
import javax.servlet.http.HttpSessionContext;

import com.quadcap.io.dir.Directory;
import com.quadcap.io.dir.Entry;

import com.quadcap.util.Debug;
import com.quadcap.util.Util;

/**
 * This class provides a wrapper for a Web Application, implementing
 * the application's ServletContext interface.
 *
 * @author Stan Bailes
 */
public class WebApplication implements ServletContext {
    WebServer                           server;
    WebClassLoader                      classLoader;
    String                              contextPath;
    
    /**
     * Map name -> Servlet
     */
    HashMap                             servlets        = new HashMap();

    /**
     * Session table: sessionId -> HttpSession
     */
    Hashtable                           sessions        = new Hashtable();

    /**
     * Servlet context attributes
     */
    Hashtable                           attributes      = new Hashtable();

    /**
     * Mime types
     */
    Hashtable                           mimeTypes       = new Hashtable();

    /**
     * Path mappings
     */
    Hashtable                           pathMappings    = new Hashtable();
    Hashtable                           extMappings     = new Hashtable();
    Hashtable                           exactMappings   = new Hashtable();

    WebServlet                          defaultServlet  = null;

    /**
     * Welcome file list
     */
    List                                welcomeFiles    = new ArrayList();
    
    /**
     * Error page
     */
    String                              errorPage       = null;

    /**
     * My document root
     */
    Directory                           docRoot;

    String                              displayName     = "";

    long                                sessionCount    = 0;
    int                                 sessionTimeout  = 3600;

    Properties                          initParams   = new Properties();

    public WebApplication() {}

    public void init(WebServer server, String root, Directory dir)
        throws ServletException, IOException
    {
        //#ifdef DEBUG
        if (Trace.level() > 0) {
            Debug.println(toString() + ".init(" + root + ", " +
                          dir.getRootPath() + ")");
        }
        //#endif
        this.server = server;
        this.docRoot = dir;
        this.contextPath = root;

        File tmp = server.getTempDir();
        File myTmp = new File(tmp, root);
        if (!myTmp.isDirectory() && !myTmp.mkdirs()) {
            throw new ServletException("Can't create repository: " + myTmp);
        }
        setAttribute("repository", myTmp);
        classLoader = new WebClassLoader(dir, myTmp);
        classLoader.init();
        attributes.put("com.quadcap.classLoader", classLoader);
        InputStream dis = ClassLoader.getSystemResourceAsStream(
            "com/quadcap/http/server22/defaultContext.xml");
        if (dis == null) {
            throw new ServletException("Can't load default context");
        }
        Reader dfr = new InputStreamReader(dis);
        try {
            parseDeploymentDescriptor(dfr);
        } finally {
            dfr.close();
        }
        setDisplayName("");
        
        Entry entry = dir.getEntry("WEB-INF/web.xml");
        if (entry != null) {
            Reader ddr = new InputStreamReader(entry.getInputStream());
            try {
                parseDeploymentDescriptor(ddr);
            } finally {
                ddr.close();
            }
        }
        resolveServlets(pathMappings);
        resolveServlets(extMappings);
        resolveServlets(exactMappings);
        loadInitialServlets();
    }

    public void shutdown() {
        synchronized (sessions) {
            Enumeration e = sessions.keys();
            while (e.hasMoreElements()) {
                String sessionId = (String)e.nextElement();
                HSession session = (HSession)getSession(sessionId);
                session.invalidate();
            }
        }
        if (docRoot != null) {
            try {
                docRoot.close();
            } catch (Throwable t) {}
        }
    }

    final void resolveServlets(Hashtable t) {
        Enumeration e = t.keys();
        while (e.hasMoreElements()) {
            Object key = e.nextElement();
            Object obj = t.get(key);
            if (obj instanceof String) {
                Object s = servlets.get(obj);
                if (s == null) {
                    Debug.println("No servlet for mapping: " + obj);
                    t.remove(key);
                } else {
                    t.put(key, s);
                }
            }
        }
    }

    void parseDeploymentDescriptor(Reader r)
        throws ServletException, IOException {
        try {
            new DDParser().parse(r, this);
        } catch (Exception e) {
            throw new ServletException(e);
        } finally {
            r.close();
        }
    }

    public void setDisplayName(String name) {
        this.displayName = name;
    }

    public String getDisplayName() {
        return displayName;
    }

    public void addInitParam(String prop, String val) {
        initParams.setProperty(prop, val);
    }

    public Enumeration getInitParameterNames() {
        return initParams.keys();
    }

    public String getInitParameter(String name) {
        return initParams.getProperty(name);
    }

    public void addWelcomeFile(String s) {
        welcomeFiles.add(s.trim());
    }

    public List getWelcomeFiles() {
        if (welcomeFiles.size() == 0) {
            welcomeFiles.add("index.html");
            welcomeFiles.add("index.jsp");
        }
        return welcomeFiles;
    }

    public void addServlet(WebServlet servlet) {
        //#ifdef DEBUG
        if (Trace.level() > 1) {
            Debug.println(toString() + ".addServlet(" +
                          servlet.getServletName() + ")");
        }
        //#endif
        servlets.put(servlet.getServletName(), servlet);
    }

    WebServlet getServletForRequest(HttpDispatcher rd) {
        String path = rd.getServletPath();
        
        WebServlet s = (WebServlet)exactMappings.get(path);
        if (s != null) {
            rd.setServlet(s, path);
        } else {
            int lastDot = -1;
            for (int i = path.length() - 1; i >= 0; i--) {
                char c = path.charAt(i);
                if (c == '/') {
                    String subPath = path.substring(0, i);
                    s = (WebServlet)pathMappings.get(subPath);
                    if (s != null) {
                        rd.setServlet(s, subPath);
                        rd.setPathInfo(path.substring(i));
                        break;
                    }
                } else if (c == '.' && lastDot < 0) {
                    lastDot = i;
                }
            }
            if (s == null && lastDot >= 0) {
                String ext = path.substring(lastDot + 1);
                s = (WebServlet)extMappings.get(ext);
                if (s != null) {
                    rd.setServlet(s, path);
                }
            }
            if (s == null) {
                s = defaultServlet;
                rd.setServlet(s, path);
            }
        }
        //#ifdef DEBUG
        if (Trace.level() > 1) {
            Debug.println(toString() + ".getServlet(" + path + ") = " + s);
        }
        //#endif
        return s;
    }

    public void setSessionTimeout(int timeout) {
        this.sessionTimeout = timeout;
    }

    public int getSessionTimeout() {
        return sessionTimeout;
    }

    public void addServletMapping(String servletName, String urlPattern) {
        //#ifdef DEBUG
        if (Trace.level() > 0) {
            Debug.println(this + ".addServletMapping(" + servletName +
                          ", " + urlPattern + ")");
        }
        //#endif
        
        if (urlPattern.equals("*.*")) {
            defaultServlet = (WebServlet)servlets.get(servletName);
        } else if (urlPattern.endsWith("*")) {
            String path = urlPattern.substring(0, urlPattern.length() - 2);
            pathMappings.put(path, servletName);
        } else if (urlPattern.startsWith("*.")) {
            String ext = urlPattern.substring(2);
            extMappings.put(ext, servletName);
        } else {
            exactMappings.put(urlPattern, servletName);
        }
    }

    public void setErrorPage(String errorPage) {
        this.errorPage = errorPage;
    }

    public String getErrorPage() {
        return errorPage;
    }

    public Object getAttribute(String name) {
        return attributes.get(name);
    }

    public Enumeration getAttributeNames() {
        return attributes.keys();
    }

    public void setAttribute(String name, Object val) {
        attributes.put(name, val);
    }

    public void removeAttribute(String name) {
        attributes.remove(name);
    }

    /**
     * Returns the name and version of the network service under which the
     * servlet is running.
     *
     * @return the server information string
     */
    public String getServerInfo() {
        //> return \"Quadcap Web Server [defined VERSION]\";
//#autogen begin
         return "Quadcap Web Server 3.4";
//#autogen end
    }

    /**
     * Return the server major version number
     */
    public int getMajorVersion() { 
         return 2;
    }

    /**
     * Return the server minor version number
     */
    public int getMinorVersion() { 
         return 2;
    }

    public ServletContext getContext(String path) {
        return server.getContext(path);
    }

    /**
     * @param path is a string that must begin with '/' and is interpreted
     * relative to this context's root
     */
    public RequestDispatcher getRequestDispatcher(String path) {
        HttpDispatcher rd = new HttpDispatcher(this, path);
        WebServlet ws = getServletForRequest(rd);
        return (ws != null) ? rd : null;
    }

    public RequestDispatcher getNamedDispatcher(String name) {
        WebServlet ws = (WebServlet)servlets.get(name);
        if (ws != null) {
            return new HttpDispatcher(ws, name);
        } else {
            return null;
        }
    }
        
    public RequestDispatcher getRelativeRequestDispatcher(String path,
                                                          HttpRequest base) {
        if (path.charAt(0) == '/') {
            return getRequestDispatcher(path);
        } else {
            String spath = base.getServletPath();
            int spos = spath.length() - 1;
            while (spos >= 0 && spath.charAt(spos) != '/') spos--;
            
            while (path.startsWith("./") || path.startsWith("../")) {
                if (path.startsWith("./")) {
                    path = path.substring(2);
                } else {
                    if (spos > 0) {
                        spos--;
                        while (spos >= 0 && spath.charAt(spos) != '/') spos--;
                    } else {
                        return null;
                    }
                }
            }
            String absPath = spath.substring(0, spos+1) + path;
            return getRequestDispatcher(absPath);
        }
    }

    void addMimeMapping(String ext, String type) {
        //#ifdef DEBUG
        if (Trace.level() > 0) {
            Debug.println(toString() + ".addMimeMapping(" + ext +
                          ", " + type + ")");
        }
        //#endif
        mimeTypes.put(ext, type);
    }

    public String getMimeType(String file) {
        String type = null;
        int lastDot = file.lastIndexOf('.');
        int lastSep = file.lastIndexOf('/');
        if (lastDot != -1 && (lastSep == -1 || lastDot > lastSep)) {
            String ext = file.substring(lastDot + 1);
            type = (String)mimeTypes.get(ext);
            if (type == null) {
                type = server.getMimeTypeForExt(ext);
            }
        }
        return type;
    }

    /**
     * If a URI refers to a directory, use the welcome file list to find
     * a resource in the directory to serve.  Return the name of the file
     * if found, otherwise, simply return the original directory name.
     */
    String resolveDirectory(String path) {
        String ret = path;
        String sav = path + "/";
        if (sav.endsWith("//")) {
            sav = sav.substring(0, sav.length()-1);
        }
        Entry e = docRoot.getEntry(path);
        if (e != null) {
            if (e.isDirectory()) {
                e = null;
                List w = getWelcomeFiles();
                for (int i = 0; e == null && i < w.size(); i++) {
                    e = docRoot.getEntry(path = sav + w.get(i));
                }
            }
        }
        if (e != null) ret = path;
        return ret;
    }

    public String getRealPath(String path) {
        String rpath = resolveDirectory(path);
        String ret = docRoot.getRealPath(rpath);
        return ret;
    }

    public URL getResource(String path) throws MalformedURLException {
        return docRoot.getURL(path);
    }

    public InputStream getResourceAsStream(String path) {
        try {
            URL url = getResource(path);
            if (url != null) {
                return url.openStream();
            }
        } catch (Throwable t) {}
        return null;
    }

    /**
     * Returns the session bound to the specified session ID. 
     *
     * @param sessionID the ID of a particular session object
     * @return the session name. Returns null if the session ID does not refer
     * to a valid session.
     */
    public HSession getSession(String sessionId) {
        synchronized (sessions) {
            return (HSession)sessions.get(sessionId);
        }
    }
  
    void removeSession(HSession session) {
        //#ifdef DEBUG
        if (Trace.level() > 1) {
            Debug.println("removeSession(" + session.getId() + ")");
        }
        //#endif
        synchronized (sessions) {
            sessions.remove(session.getId());
        }
    }

    /**
     * Create a new session
     */
    public HSession createSession() {
        String sessionId = server.makeSessionId();
        //#ifdef DEBUG
        if (Trace.level() > 1) {
            Debug.println("++++++ createSession(): " + sessionId);
        }
        //#endif
        HSession session = new HSession(this, sessionId, sessionTimeout);
        synchronized (sessions) {
            sessions.put(sessionId, session);
        }
        return session;
    }

    /**
     * Reap any expired sessions (sessions not active during the last
     * interval)
     */
    public void expireSessions() {
        synchronized (sessions) {
            Enumeration e = sessions.keys();
            long now = System.currentTimeMillis();
            while (e.hasMoreElements()) {
                String sessionId = (String)e.nextElement();
                HSession session = (HSession)getSession(sessionId);
                if (now - session.getLastAccessedTime() >
                    (session.getMaxInactiveInterval() * 1000)) {
                    try {
                        session.invalidate();
                    } catch (Throwable t) {
                        Debug.print(t);
                    }
                }
            }
        }
    }

    /**
     * Writes a message to the server's log file.
     *
     * @param msg the message
     */
    public void log(String msg) {
        Debug.println(msg);
    }

    /**
     * Write the stack backtrace for the exception and the specified message
     * to the server's log file.
     *
     * @param e the exception
     * @param msg the message
     * @deprecated
     */
    public void log(Exception e, String msg) {
        Debug.println(msg);
        Debug.print(e);
    }

    /**
     * Write the stack backtrace for the exception and the specified message
     * to the server's log file.
     *
     * @param e the exception
     * @param msg the message
     */
    public void log(String msg, Throwable e) {
        Debug.println(msg);
        Debug.print(e);
    }
    
    /**
     * @deprecated in 2.2
     */
    public Servlet getServlet(String name) {
        return null;
    }

    /**
     * @deprecated in 2.2
     */
    public Enumeration getServletNames() {
        return new Vector().elements();
    }

    /**
     * @deprecated in 2.2
     */
    public Enumeration getServlets() {
        return new Vector().elements();
    }

    public String getContextPath() {
        return contextPath;
    }

    /**
     * Return the classpath for the context's libraries and classes
     * under WEB-INF.
     */
    public String getContextClassPath() {
        return classLoader.getClassPath();
    }

    final ClassLoader getClassLoader() {
        return classLoader;
    }

    final void loadInitialServlets() throws ServletException {
        ServletException ex = null;
        
        ArrayList l = new ArrayList();
        l.addAll(servlets.values());
        Collections.sort(l, new Comparator() {
            public int compare(Object a, Object b) {
                WebServlet wa = (WebServlet)a;
                WebServlet wb = (WebServlet)b;
                if (wa.getLoadOnStartup() < wb.getLoadOnStartup()) return -1;
                if (wa.getLoadOnStartup() > wb.getLoadOnStartup()) return 1;
                return 0;
            }
        });
        for (int i = 0; i < l.size(); i++) {
            WebServlet w = (WebServlet)l.get(i);
            if (w.getLoadOnStartup() >= 0) {
                try {
                    w.init();
                } catch (ServletException e) {
                    ex = e;
                    Debug.print(e);
                }
            }
        }

        if (ex != null) throw ex;
    }

    public WebServer getWebServer() { return server; }

    public String getRootPath() { return docRoot.getRootPath(); }

    public boolean isDirectory(String d) {
        try {
            return docRoot.getEntry(d).isDirectory();
        } catch (Throwable t) {
            return false;
        }
    }

    //#ifdef DEBUG
    public String toString() {
        return "[" + contextPath + "]";
    }
    //#endif
}