tldconfig.java

业界著名的tomcat服务器的最新6.0的源代码。

/*
 * 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.catalina.startup;


import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.net.URL;
import java.net.URLClassLoader;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import java.util.StringTokenizer;
import java.util.jar.JarEntry;
import java.util.jar.JarFile;

import javax.naming.NameClassPair;
import javax.naming.NamingEnumeration;
import javax.naming.NamingException;
import javax.naming.directory.DirContext;
import javax.servlet.ServletException;

import org.apache.catalina.Context;
import org.apache.catalina.Globals;
import org.apache.catalina.core.StandardContext;
import org.apache.catalina.util.StringManager;
import org.apache.tomcat.util.digester.Digester;
import org.xml.sax.InputSource;

/**
 * Startup event listener for a <b>Context</b> that configures the properties
 * of that Context, and the associated defined servlets.
 *
 * @author Craig R. McClanahan
 * @author Jean-Francois Arcand
 * @author Costin Manolache
 */
public final class TldConfig  {

    // Names of JARs that are known not to contain any TLDs
    private static HashSet<String> noTldJars;

    private static org.apache.juli.logging.Log log=
        org.apache.juli.logging.LogFactory.getLog( TldConfig.class );

    /*
     * Initializes the set of JARs that are known not to contain any TLDs
     */
    static {
        noTldJars = new HashSet<String>();
        // Bootstrap JARs
        noTldJars.add("bootstrap.jar");
        noTldJars.add("commons-daemon.jar");
        noTldJars.add("tomcat-juli.jar");
        // Main JARs
        noTldJars.add("annotations-api.jar");
        noTldJars.add("catalina.jar");
        noTldJars.add("catalina-ant.jar");
        noTldJars.add("catalina-ha.jar");
        noTldJars.add("catalina-tribes.jar");
        noTldJars.add("el-api.jar");
        noTldJars.add("jasper.jar");
        noTldJars.add("jasper-el.jar");
        noTldJars.add("jasper-jdt.jar");
        noTldJars.add("jsp-api.jar");
        noTldJars.add("servlet-api.jar");
        noTldJars.add("tomcat-coyote.jar");
        noTldJars.add("tomcat-dbcp.jar");
        // i18n JARs
        noTldJars.add("tomcat-i18n-en.jar");
        noTldJars.add("tomcat-i18n-es.jar");
        noTldJars.add("tomcat-i18n-fr.jar");
        noTldJars.add("tomcat-i18n-ja.jar");
        // Misc JARs not included with Tomcat
        noTldJars.add("ant.jar");
        noTldJars.add("commons-dbcp.jar");
        noTldJars.add("commons-beanutils.jar");
        noTldJars.add("commons-fileupload-1.0.jar");
        noTldJars.add("commons-pool.jar");
        noTldJars.add("commons-digester.jar");
        noTldJars.add("commons-logging.jar");
        noTldJars.add("commons-collections.jar");
        noTldJars.add("jmx.jar");
        noTldJars.add("jmx-tools.jar");
        noTldJars.add("xercesImpl.jar");
        noTldJars.add("xmlParserAPIs.jar");
        noTldJars.add("xml-apis.jar");
        // JARs from J2SE runtime
        noTldJars.add("sunjce_provider.jar");
        noTldJars.add("ldapsec.jar");
        noTldJars.add("localedata.jar");
        noTldJars.add("dnsns.jar");
        noTldJars.add("tools.jar");
        noTldJars.add("sunpkcs11.jar");
    }


    // ----------------------------------------------------- Instance Variables

    /**
     * The Context we are associated with.
     */
    private Context context = null;


    /**
     * The string resources for this package.
     */
    private static final StringManager sm =
        StringManager.getManager(Constants.Package);

    /**
     * The <code>Digester</code> we will use to process tag library
     * descriptor files.
     */
    private static Digester tldDigester = null;


    /**
     * Attribute value used to turn on/off TLD validation
     */
     private static boolean tldValidation = false;


    /**
     * Attribute value used to turn on/off TLD  namespace awarenes.
     */
    private static boolean tldNamespaceAware = false;

    private boolean rescan=true;

    private ArrayList<String> listeners = new ArrayList<String>();

    // --------------------------------------------------------- Public Methods

    /**
     * Sets the list of JARs that are known not to contain any TLDs.
     *
     * @param jarNames List of comma-separated names of JAR files that are 
     * known not to contain any TLDs 
     */
    public static void setNoTldJars(String jarNames) {
        if (jarNames != null) {
            noTldJars.clear();
            StringTokenizer tokenizer = new StringTokenizer(jarNames, ",");
            while (tokenizer.hasMoreElements()) {
                noTldJars.add(tokenizer.nextToken());
            }
        }
    }

    /**
     * Set the validation feature of the XML parser used when
     * parsing xml instances.
     * @param tldValidation true to enable xml instance validation
     */
    public void setTldValidation(boolean tldValidation){
        TldConfig.tldValidation = tldValidation;
    }

    /**
     * Get the server.xml <host> attribute's xmlValidation.
     * @return true if validation is enabled.
     *
     */
    public boolean getTldValidation(){
        return tldValidation;
    }

    /**
     * Get the server.xml <host> attribute's xmlNamespaceAware.
     * @return true if namespace awarenes is enabled.
     *
     */
    public boolean getTldNamespaceAware(){
        return tldNamespaceAware;
    }


    /**
     * Set the namespace aware feature of the XML parser used when
     * parsing xml instances.
     * @param tldNamespaceAware true to enable namespace awareness
     */
    public void setTldNamespaceAware(boolean tldNamespaceAware){
        TldConfig.tldNamespaceAware = tldNamespaceAware;
    }    


    public boolean isRescan() {
        return rescan;
    }

    public void setRescan(boolean rescan) {
        this.rescan = rescan;
    }

    public Context getContext() {
        return context;
    }

    public void setContext(Context context) {
        this.context = context;
    }

    public void addApplicationListener( String s ) {
        //if(log.isDebugEnabled())
            log.debug( "Add tld listener " + s);
        listeners.add(s);
    }

    public String[] getTldListeners() {
        String result[]=new String[listeners.size()];
        listeners.toArray(result);
        return result;
    }


    /**
     * Scan for and configure all tag library descriptors found in this
     * web application.
     *
     * @exception Exception if a fatal input/output or parsing error occurs
     */
    public void execute() throws Exception {
        long t1=System.currentTimeMillis();

        File tldCache=null;

        if (context instanceof StandardContext) {
            File workDir= (File)
                ((StandardContext)context).getServletContext().getAttribute(Globals.WORK_DIR_ATTR);
            //tldCache=new File( workDir, "tldCache.ser");
        }

        // Option to not rescan
        if( ! rescan ) {
            // find the cache
            if( tldCache!= null && tldCache.exists()) {
                // just read it...
                processCache(tldCache);
                return;
            }
        }

        /*
         * Acquire the list of TLD resource paths, possibly embedded in JAR
         * files, to be processed
         */
        Set resourcePaths = tldScanResourcePaths();
        Map jarPaths = getJarPaths();

        // Check to see if we can use cached listeners
        if (tldCache != null && tldCache.exists()) {
            long lastModified = getLastModified(resourcePaths, jarPaths);
            if (lastModified < tldCache.lastModified()) {
                processCache(tldCache);
                return;
            }
        }

        // Scan each accumulated resource path for TLDs to be processed
        Iterator paths = resourcePaths.iterator();
        while (paths.hasNext()) {
            String path = (String) paths.next();
            if (path.endsWith(".jar")) {
                tldScanJar(path);
            } else {
                tldScanTld(path);
            }
        }
        if (jarPaths != null) {
            paths = jarPaths.values().iterator();
            while (paths.hasNext()) {
                tldScanJar((File) paths.next());
            }
        }

        String list[] = getTldListeners();

        if( tldCache!= null ) {
            log.debug( "Saving tld cache: " + tldCache + " " + list.length);
            try {
                FileOutputStream out=new FileOutputStream(tldCache);
                ObjectOutputStream oos=new ObjectOutputStream( out );
                oos.writeObject( list );
                oos.close();
            } catch( IOException ex ) {
                ex.printStackTrace();
            }
        }

        if( log.isDebugEnabled() )
            log.debug( "Adding tld listeners:" + list.length);
        for( int i=0; list!=null && i<list.length; i++ ) {
            context.addApplicationListener(list[i]);
        }

        long t2=System.currentTimeMillis();
        if( context instanceof StandardContext ) {
            ((StandardContext)context).setTldScanTime(t2-t1);
        }

    }

    // -------------------------------------------------------- Private Methods

    /*
     * Returns the last modification date of the given sets of resources.
     *
     * @param resourcePaths
     * @param jarPaths
     *
     * @return Last modification date
     */
    private long getLastModified(Set resourcePaths, Map jarPaths)
            throws Exception {

        long lastModified = 0;

        Iterator paths = resourcePaths.iterator();
        while (paths.hasNext()) {
            String path = (String) paths.next();
            URL url = context.getServletContext().getResource(path);
            if (url == null) {
                log.debug( "Null url "+ path );
                break;
            }
            long lastM = url.openConnection().getLastModified();
            if (lastM > lastModified) lastModified = lastM;
            if (log.isDebugEnabled()) {
                log.debug( "Last modified " + path + " " + lastM);
            }