jnlpfilehandler.java

编写程序

/*
 * @(#)JnlpFileHandler.java	1.10 03/10/31
 *
 * Copyright 2004 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
package jnlp.sample.servlet;

import java.util.*;
import java.util.regex.*;
import java.net.*;
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import javax.xml.parsers.*;
import org.xml.sax.*;
import javax.xml.transform.*;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import org.w3c.dom.*;

/* The JNLP file handler implements a class that keeps
 * track of JNLP files and their specializations
 */
public class JnlpFileHandler {
    private static final String JNLP_MIME_TYPE = "application/x-java-jnlp-file";
    private static final String HEADER_LASTMOD = "Last-Modified";
    
    private ServletContext _servletContext;
    private Logger _log = null;
    private HashMap _jnlpFiles = null;
    
    /** Initialize JnlpFileHandler for the specific ServletContext */
    public JnlpFileHandler(ServletContext servletContext, Logger log) {
        _servletContext = servletContext;
        _log = log;
        _jnlpFiles = new HashMap();
    }
    
    private static class JnlpFileEntry {
        // Response
        DownloadResponse _response;
        // Keeps track of cache is out of date
        private long   _lastModified;
        
        // Constructor
        JnlpFileEntry(DownloadResponse response, long lastmodfied) {
            _response = response;
            _lastModified = lastmodfied;
        }
        
        public DownloadResponse getResponse() { return _response; }
        long getLastModified() { return _lastModified; }
    }
    
    /* Main method to lookup an entry */
    public synchronized DownloadResponse getJnlpFile(JnlpResource jnlpres, DownloadRequest dreq) 
	throws IOException {		
	String path = jnlpres.getPath();
	URL resource = jnlpres.getResource();		
	long lastModified = jnlpres.getLastModified();	
	
	
	_log.addDebug("lastModified: " + lastModified + " " + new Date(lastModified));
	if (lastModified == 0) {
	    _log.addWarning("servlet.log.warning.nolastmodified", path);
	}
	
	// fix for 4474854:  use the request URL as key to look up jnlp file
	// in hash map
	String reqUrl = HttpUtils.getRequestURL(dreq.getHttpRequest()).toString();

	// Check if entry already exist in HashMap
	JnlpFileEntry jnlpFile = (JnlpFileEntry)_jnlpFiles.get(reqUrl);

	if (jnlpFile != null && jnlpFile.getLastModified() == lastModified) {
	    // Entry found in cache, so return it
	    return jnlpFile.getResponse();   
	} 
	
	// Read information from WAR file
	long timeStamp = lastModified;
	String mimeType = _servletContext.getMimeType(path);
	if (mimeType == null) mimeType = JNLP_MIME_TYPE;
	
	StringBuffer jnlpFileTemplate = new StringBuffer();
	URLConnection conn = resource.openConnection();
	BufferedReader br = new BufferedReader(new InputStreamReader(conn.getInputStream(), "UTF-8"));
	String line = br.readLine();
	if (line != null && line.startsWith("TS:")) {
	    timeStamp = parseTimeStamp(line.substring(3));
	    _log.addDebug("Timestamp: " + timeStamp + " " + new Date(timeStamp));
	    if (timeStamp == 0) {		
		_log.addWarning("servlet.log.warning.notimestamp", path);
		timeStamp = lastModified;
	    }	    
	    line = br.readLine();   
	}
	while(line != null) {
	    jnlpFileTemplate.append(line);
	    line = br.readLine();
	}
	
	String jnlpFileContent = specializeJnlpTemplate(dreq.getHttpRequest(), path, jnlpFileTemplate.toString());
	
	// Convert to bytes as a UTF-8 encoding
	byte[] byteContent = jnlpFileContent.getBytes("UTF-8");
	
	// Create entry	
	DownloadResponse resp = DownloadResponse.getFileDownloadResponse(byteContent, 
									 mimeType, 
									 timeStamp, 
									 jnlpres.getReturnVersionId());	
	jnlpFile = new JnlpFileEntry(resp, lastModified);
	_jnlpFiles.put(reqUrl, jnlpFile);
	
	return resp;
    }   

    /* Main method to lookup an entry (NEW for JavaWebStart 1.5+) */
    public synchronized DownloadResponse getJnlpFileEx(JnlpResource jnlpres, DownloadRequest dreq)
	throws IOException {
        String path = jnlpres.getPath();
        URL resource = jnlpres.getResource();
        long lastModified = jnlpres.getLastModified();
        
        
        _log.addDebug("lastModified: " + lastModified + " " + new Date(lastModified));
        if (lastModified == 0) {
            _log.addWarning("servlet.log.warning.nolastmodified", path);
        }
        
        // fix for 4474854:  use the request URL as key to look up jnlp file
        // in hash map
        String reqUrl = HttpUtils.getRequestURL(dreq.getHttpRequest()).toString();
        // SQE: To support query string, we changed the hash key from Request URL to (Request URL + query string)
        if (dreq.getQuery() != null)
            reqUrl += dreq.getQuery();
        
        // Check if entry already exist in HashMap
        JnlpFileEntry jnlpFile = (JnlpFileEntry)_jnlpFiles.get(reqUrl);
        
        if (jnlpFile != null && jnlpFile.getLastModified() == lastModified) {
            // Entry found in cache, so return it
            return jnlpFile.getResponse();
        }
        
        // Read information from WAR file
        long timeStamp = lastModified;
        String mimeType = _servletContext.getMimeType(path);
        if (mimeType == null) mimeType = JNLP_MIME_TYPE;
        
        StringBuffer jnlpFileTemplate = new StringBuffer();
        URLConnection conn = resource.openConnection();
        BufferedReader br = new BufferedReader(new InputStreamReader(conn.getInputStream(), "UTF-8"));
        String line = br.readLine();
        if (line != null && line.startsWith("TS:")) {
            timeStamp = parseTimeStamp(line.substring(3));
            _log.addDebug("Timestamp: " + timeStamp + " " + new Date(timeStamp));
            if (timeStamp == 0) {
                _log.addWarning("servlet.log.warning.notimestamp", path);
                timeStamp = lastModified;
            }
            line = br.readLine();
        }
        while(line != null) {
            jnlpFileTemplate.append(line);
            line = br.readLine();
        }
        
        String jnlpFileContent = specializeJnlpTemplate(dreq.getHttpRequest(), path, jnlpFileTemplate.toString());
        
	/* SQE: We need to add query string back to href in jnlp file. We also need to handle JRE requirement for
	 * the test. We reconstruct the xml DOM object, modify the value, then regenerate the jnlpFileContent.
	 */
        String query = dreq.getQuery();
        String testJRE = dreq.getTestJRE();
        _log.addDebug("Double check query string: " + query);
        // For backward compatibility: Always check if the href value exists.
        // Bug 4939273: We will retain the jnlp template structure and will NOT add href value. Above old
        // approach to always check href value caused some test case not run.
        if (query != null) {
            byte [] cb = jnlpFileContent.getBytes("UTF-8");
            ByteArrayInputStream bis = new ByteArrayInputStream(cb);
            try {
                DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
                DocumentBuilder builder = factory.newDocumentBuilder();
                Document document = builder.parse(bis);
                if (document != null && document.getNodeType() == Node.DOCUMENT_NODE) {
                    boolean modified = false;
                    Element root = document.getDocumentElement();
                    /**
                     *  This part is for VM Args Test. If the query string has any parameter
                     * with VM-Args= then this block will add /replace the java-vm-args attribute
                     * with the value given in the VM-Args parameter. The more than one VM-Args
                     * should be seperated using "+" symbol i.e. the query string should comply
                     * with the standard format of the query string.
                     *
                     * Added By Elancheran 09/12/03
                     */
                    String vmArgs = null;
                    if( query != null && query.indexOf("VM-Args") != -1) {
                        String tempStr = query.substring(query.indexOf("VM-Args=") + 8);
                        if(tempStr.indexOf('&') != -1)
                            vmArgs = tempStr.substring(0, tempStr.indexOf('&'));
                        vmArgs = tempStr;
                        vmArgs = vmArgs.replace('+', ' ');
                        _log.addDebug("VM-Args given in the query string: " + vmArgs);
                    }