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The source code

/*****************************************************************************
 * Sun Public License Notice
 *
 * The contents of this file are subject to the Sun Public License Version
 * 1.0 (the "License"). You may not use this file except in compliance with
 * the License. A copy of the License is available at http://www.sun.com/
 *
 * The Original Code is the CVS Client Library.
 * The Initial Developer of the Original Code is Robert Greig.
 * Portions created by Robert Greig are Copyright (C) 2000.
 * All Rights Reserved.
 *
 * Contributor(s): Robert Greig.
 *****************************************************************************/
package org.netbeans.lib.cvsclient;

import java.io.*;
import java.util.*;

import org.netbeans.lib.cvsclient.admin.*;
import org.netbeans.lib.cvsclient.command.*;
import org.netbeans.lib.cvsclient.connection.*;
import org.netbeans.lib.cvsclient.event.*;
import org.netbeans.lib.cvsclient.file.*;
import org.netbeans.lib.cvsclient.request.*;
import org.netbeans.lib.cvsclient.response.*;
import org.netbeans.lib.cvsclient.util.*;

/**
 * The main way of communication with a server using the CVS Protocol. The
 * client is not responsible for setting up the connection with the server,
 * only interacting with it.
 * @see org.netbeans.lib.cvsclient.connection.Connection
 * @author  Robert Greig
 */
public class Client implements ClientServices, ResponseServices {
    /**
     * The connection used to interact with the server.
     */
    private Connection connection;

    /**
     * The file handler to use.
     */
    private FileHandler transmitFileHandler;

    private FileHandler gzipFileHandler = new GzippedFileHandler();
    private FileHandler uncompFileHandler = new DefaultFileHandler();

    private boolean dontUseGzipFileHandler;

    /**
     * The modified date.
     */
    private Date modifiedDate;

    /**
     * The admin handler to use.
     */
    private AdminHandler adminHandler;

    /**
     * The local path, ie the path to the directory in which this command
     * was executed.
     */
    private String localPath;

    /**
     * Whether any commands have been executed so far. This allows us to
     * send some initialisation requests before the first command.
     */
    private boolean isFirstCommand = true;

    /**
     * The event manager.
     */
    private final EventManager eventManager = new EventManager();

    /**
     * The global options for the executing command.
     */
    private GlobalOptions globalOptions;

    /**
     * This is set to true if we should abort the current command.
     */
    private boolean abort;
    
    private ResponseFactory responseFactory;

    private IgnoreFileFilter ignoreFileFilter;
    
    /*
     * The valid list of requests that is valid for the CVS server
     * corresponding to this client
     */
    private Map validRequests = new HashMap();
    
    /**
     * A map of file patterns and keyword substitution options
     */
    private Map wrappersMap = null;
    
    /**
     * This will be set to true after initialization requests are sent
     * to the server. The initialization requests setup valid requests
     * and send RootRequest to the server.
     */
    private boolean initialRequestsSent = false;
    
    private boolean printConnectionReuseWarning = false;
    
    private static final Set ALLOWED_CONNECTION_REUSE_REQUESTS = 
        new HashSet(Arrays.asList(new Class[] { ExpandModulesRequest.class, WrapperSendRequest.class }));

    /**
     * Construct a Client using a given connection and file handler.
     * You must initialize the connection and adminHandler first.
     * 
     *  // establish connection to the given CVS pserver
     *  PServerConnection connection = new PServerConnection();
     *  connection.setUserName(userName);
     *  connection.setHostName(hostName);
     *  connection.setEncodedPassword(StandardScrambler.getInstance().scramble(password));
     *  connection.setRepository(repository);
     *  // test the connection
     *  try {
     *      connection.open();
     *  } catch (AuthenticationException e) {
     *      // do something
     *  }
     *
     *  // create a CVS client
     *  Client cvsClient = new Client(connection,new StandardAdminHandler());
     *
     *  // set the directory in which we work
     *  cvsClient.setLocalPath(localPath);
     * 
     * @param connection the connection to the cvs server
     * @param adminHandler the admin handler to use
     */
    public Client(Connection connection, AdminHandler adminHandler) {
        setConnection(connection);
        setAdminHandler(adminHandler);
        ignoreFileFilter = new DefaultIgnoreFileFilter();
        dontUseGzipFileHandler = false;
    }

    /**
     * Get the connection used for communicating with the server.
     * Connection.
     * @return the connection
     */
    public Connection getConnection() {
        return connection;
    }

    /**
     * Set the connection used for communicating with the server.
     * @param c the connection to use for all communication with the server
     */
    public void setConnection(Connection connection) {
        this.connection = connection;
        initialRequestsSent = false;
        setIsFirstCommand(true);
    }

    /**
     * Get the admin handler uesd to read and write administrative information
     * about files on the local machine.
     * @return the admin handler
     */
    public AdminHandler getAdminHandler() {
        return adminHandler;
    }

    /**
     * Set the admin handler used to read and write administrative information
     * about files on the local machine.
     */
    public void setAdminHandler(AdminHandler adminHandler) {
        this.adminHandler = adminHandler;
    }

    /**
     * Get the local path; that is, the path to the directory in which
     * the currently executing command is referring.
     */
    public String getLocalPath() {
        return localPath;
    }

    /**
     * Set the local path, i.e. the path to the directory in which all
     * commands are given (top level).
     */
    public void setLocalPath(String localPath) {
        // remove trailing (back-) slash
        localPath = localPath.replace('\\', '/');
        while (localPath.endsWith("/")) { // NOI18N
            localPath = localPath.substring(0, localPath.length() - 1);
        }

        this.localPath = localPath;
    }

    /**
     * Returns true if no previous command was executed using thiz.
     */
    public boolean isFirstCommand() {
        return isFirstCommand;
    }

    /**
     * Set whether this is the first command. Normally you do not need to set
     * this yourself - after execution the first command will have set this to
     * false.
     */
    public void setIsFirstCommand(boolean isFirstCommand) {
        this.isFirstCommand = isFirstCommand;
    }

    /**
     * Return the uncompressed file handler.
     */
    public FileHandler getUncompressedFileHandler() {
        return uncompFileHandler;
    }

    /**
     * Set the uncompressed file handler.
     */
    public void setUncompressedFileHandler(FileHandler uncompFileHandler) {
        this.uncompFileHandler = uncompFileHandler;
    }

    /**
     * Return the Gzip stream handler.
     */
    public FileHandler getGzipFileHandler() {
        return gzipFileHandler;
    }

    /**
     * Set the handler for Gzip data.
     */
    public void setGzipFileHandler(FileHandler gzipFileHandler) {
        this.gzipFileHandler = gzipFileHandler;
    }

    /**
     * ReSet the filehandler for Gzip compressed data. Makes sure the
     * requests for sending gzipped data are not sent..
     */
    public void dontUseGzipFileHandler() {
        setGzipFileHandler(new DefaultFileHandler());
        dontUseGzipFileHandler = true;
    }

    /**
     * Ensures, that the connection is open.
     *
     * @throws AuthenticationException if it wasn't possible to connect
     */
    public void ensureConnection() throws AuthenticationException {
        BugLog.getInstance().assertNotNull(getConnection());

        if (getConnection().isOpen()) {
            return;
        }

//        getConnection().verify(); //VERIFY DOES THE SAME AS OPEN!!
        // opening a conection and then closing it and reopening again is wierd.
        try {
            getConnection().open();
        } catch (CommandAbortedException caex) {
            abort();
        }
    }

    /**
     * Process all the requests. The connection must have been opened and
     * set first.
     * @param requests the requets to process
     */
    public void processRequests(List requests)
            throws IOException, UnconfiguredRequestException, ResponseException,
            CommandAbortedException {
        if (requests == null || requests.size() == 0) {
            throw new IllegalArgumentException("[processRequests] requests " + // NOI18N
                                               "was either null or empty."); // NOI18N
        }

        if (abort) {
            throw new CommandAbortedException("Aborted during request processing", // NOI18N
                                              CommandException.getLocalMessage("Client.commandAborted", null)); //NOI18N
        }

        // send the initialisation requests if we are handling the first
        // command
        boolean filterRootRequest = true;
        if (isFirstCommand()) {
            setIsFirstCommand(false);
            int pos = 0;
            if (!initialRequestsSent) {
                pos = fillInitialRequests(requests);
                initialRequestsSent = true;
                filterRootRequest = false;
            }
            if (globalOptions != null) {
                // sends the global options that are to be sent to server (-q, -Q, -t, -n, l)
                for (Iterator it = globalOptions.createRequestList().iterator(); it.hasNext();) {
                    Request request = (Request)it.next();
                    requests.add(pos++, request);
                }

                if (globalOptions.isUseGzip()) {
                    requests.add(pos++, new GzipFileContentsRequest(globalOptions.getCompressionLevel()));
                }
            }
        } else if (printConnectionReuseWarning) {
            if (System.getProperty("javacvs.multiple_commands_warning") == null) { //NOI18N
                System.err.println("WARNING TO DEVELOPERS:"); //NOI18N
                System.err.println("Please be warned that attempting to reuse one open connection for more commands is not supported by cvs servers very well."); //NOI18N
                System.err.println("You are advised to open a new Connection each time."); //NOI18N
                System.err.println("If you still want to proceed, please do: System.setProperty(\"javacvs.multiple_commands_warning\", \"false\")"); //NOI18N
                System.err.println("That will disable this message."); //NOI18N
            }
        }
        
        if (!ALLOWED_CONNECTION_REUSE_REQUESTS.contains(requests.get(requests.size() - 1).getClass())) {
            printConnectionReuseWarning = true;
        }

        final boolean fireEnhancedEvents = getEventManager().isFireEnhancedEventSet();
        int fileDetailRequestCount = 0;

        if (fireEnhancedEvents) {
            for (Iterator it = requests.iterator(); it.hasNext();) {
                Request request = (Request)it.next();

                FileDetails fileDetails = request.getFileForTransmission();
                if (fileDetails != null && fileDetails.getFile().exists()) {
                    fileDetailRequestCount++;
                }
            }
            CVSEvent event = new EnhancedMessageEvent(this,
                                                      EnhancedMessageEvent.REQUESTS_COUNT,
                                                      new Integer(fileDetailRequestCount));
            getEventManager().fireCVSEvent(event);
        }

        LoggedDataOutputStream dos = connection.getOutputStream();

        // this list stores stream modification requests, each to be called
        // to modify the input stream the next time we need to process a
        // response
        List streamModifierRequests = new LinkedList();

        // sending files does not seem to allow compression
        transmitFileHandler = getUncompressedFileHandler();

        for (Iterator it = requests.iterator(); it.hasNext();) {
            if (abort) {
                throw new CommandAbortedException("Aborted during request processing", // NOI18N
                                                  CommandException.getLocalMessage("Client.commandAborted", null)); //NOI18N
            }

            final Request request = (Request)it.next();

            if (request instanceof GzipFileContentsRequest) {
                if (dontUseGzipFileHandler) {
                    continue;
                }
            }
            
            // skip the root request if already sent
            if (request instanceof RootRequest) {
                if (filterRootRequest) {
                    continue;
                } else { // Even if we should not filter the RootRequest now, we must filter all successive RootRequests
                    filterRootRequest = true;
                }
            }
            // send request to server
            String requestString = request.getRequestString();
            dos.writeBytes(requestString);

            // we must modify the outputstream now, but defer modification
            // of the inputstream until we are about to read a response.
            // This is because some modifiers (e.g. gzip) read the header
            // on construction, and obviously no header is present when
            // no response has been sent
            request.modifyOutputStream(connection);
            if (request.modifiesInputStream()) {
                streamModifierRequests.add(request);
            }
            dos = connection.getOutputStream();

            FileDetails fileDetails = request.getFileForTransmission();
            if (fileDetails != null) {
                final File file = fileDetails.getFile();
                // only transmit the file if it exists! When committing
                // a remove request you cannot transmit the file
                if (file.exists()) {
                    Logger.logOutput("\n"); // NOI18N

                    if (fireEnhancedEvents) {
                        CVSEvent event = new EnhancedMessageEvent(this,
                                                                  EnhancedMessageEvent.FILE_SENDING,
                                                                  file);
                        getEventManager().fireCVSEvent(event);

                        fileDetailRequestCount--;
                    }

                    if (fileDetails.isBinary()) {
                        transmitFileHandler.transmitBinaryFile(file, dos);
                    }
                    else {
                        transmitFileHandler.transmitTextFile(file, dos);
                    }

                    if (fireEnhancedEvents && fileDetailRequestCount == 0) {
                        CVSEvent event = new EnhancedMessageEvent(this,
                                                                  EnhancedMessageEvent.REQUESTS_SENT,
                                                                  "Ok"); // NOI18N
                        getEventManager().fireCVSEvent(event);
                    }
                }
            }
            if (request.isResponseExpected()) {
                dos.flush();

                // now perform the deferred modification of the input stream
                Iterator modifiers = streamModifierRequests.iterator();
                while (modifiers.hasNext()) {
                    System.err.println("Modifying the inputstream..."); // NOI18N
                    final Request smRequest = (Request)modifiers.next();
                    System.err.println("Request is a: " + // NOI18N
                                       smRequest.getClass().getName());
                    smRequest.modifyInputStream(connection);
                }
                streamModifierRequests.clear();

                handleResponse();
            }
        }
        dos.flush();

        transmitFileHandler = null;
    }
    
    private ResponseFactory getResponseFactory() {
        if (responseFactory == null) {
            responseFactory = new ResponseFactory();
        }
        return responseFactory;
    }

    /**
     * Handle the response from a request.
     * @throws ResponseException if there is a problem reading the response
     */
    private void handleResponse()
            throws ResponseException, CommandAbortedException {
        try {
            LoggedDataInputStream dis = connection.getInputStream();

            int ch = dis.readByte();
            // read in all the responses
            if (Thread.interrupted()) {
                abort();
            }

            while (!abort && ch != -1) {
                StringBuffer responseNameBuffer = new StringBuffer();
                // read in the response name
                while (ch != -1 &&
                        (char)ch != '\n' &&
                        (char)ch != ' ') {
                    responseNameBuffer.append((char)ch);
                    ch = dis.readByte();
                    if (Thread.interrupted()) {
                        abort();
                        break;
                    }
                }

                String responseString = responseNameBuffer.toString();
                Response response = getResponseFactory().createResponse(responseString);
                response.process(dis, this);
                if (response.isTerminalResponse() || abort) {
                    break;
                }
                ch = dis.readByte();
                if (Thread.interrupted()) {
                    abort();
                    break;
                }
            }

            if (abort) {
                String localMsg = CommandException.getLocalMessage("Client.commandAborted", null); //NOI18N
                throw new CommandAbortedException("Aborted during request processing", localMsg); // NOI18N
            }
        }
        catch (EOFException ex) {
            throw new ResponseException(ex, ResponseException.getLocalMessage("CommandException.EndOfFile", null)); //NOI18N
        }
        catch (IOException ex) {
            throw new ResponseException(ex);
        }
    }

    /**
     * Execute a command. Do not forget to initialize the CVS Root on globalOptions first!
     * Example:
     * 
     *   GlobalOptions options = new GlobalOptions();
     *   options.setCVSRoot(":pserver:"+userName+"@"+hostName+":"+cvsRoot);
     * 
     * @param command the command to execute
     * @param options the global options to use for executing the command
     * @throws CommandException if an error occurs when executing the command
     * @throws CommandAbortedException if the command is aborted
     */
    public boolean executeCommand(Command command, GlobalOptions globalOptions)
            throws CommandException, CommandAbortedException, AuthenticationException {
        BugLog.getInstance().assertNotNull(command);
        BugLog.getInstance().assertNotNull(globalOptions);

        this.globalOptions = globalOptions;

        getUncompressedFileHandler().setGlobalOptions(globalOptions);
        getGzipFileHandler().setGlobalOptions(globalOptions);

        try {
            eventManager.addCVSListener(command);
            command.execute(this, eventManager);
        }
        finally {
            eventManager.removeCVSListener(command);
        }
        return !command.hasFailed();
    }

    /**
     * Convert a pathname in the CVS sense (see 5.10 in the protocol
     * document) into a local absolute pathname for the file.
     * @param localDirectory the name of the local directory, relative to the
     * directory in which the command was given
     * @param repository the full repository name for the file
     */
    public String convertPathname(String localDirectory, String repository) {
        int lastIndexOfSlash = repository.lastIndexOf('/');
        String filename = repository.substring(lastIndexOfSlash + 1);

        if (localDirectory.startsWith("./")) { // NOI18N
            // remove the dot
            localDirectory = localDirectory.substring(1);
        }
        if (localDirectory.startsWith("/")) { // NOI18N
            // remove the leading slash
            localDirectory = localDirectory.substring(1);
        }
        // note that the localDirectory ends in a slash
        return getLocalPath() + '/' + localDirectory + filename;
    }

    /**
     * Get the repository path from the connection.
     *
     * @return the repository path, e.g. /home/bob/cvs. Delegated to the
     * Connection in this case
     * @see Connection#getRepository()
     */
    public String getRepository() {
        return connection.getRepository();
    }

    /**
     * Create or update the administration files for a particular file.
     * This will create the CVS directory if necessary, and the
     * Root and Repository files if necessary. It will also update
     * the Entries file with the new entry
     * @param localDirectory the local directory, relative to the directory
     * in which the command was given, where the file in question lives
     * @param repositoryPath the path of the file in the repository, in
     * absolute form.
     * @param entry the entry object for that file
     */
    public void updateAdminData(String localDirectory, String repositoryPath,
                                Entry entry)
            throws IOException {
        final String absolutePath = localPath + '/' + localDirectory;
        repositoryPath = repositoryPath.substring(getRepository().length() + 1);
        adminHandler.updateAdminData(absolutePath, repositoryPath, entry,
                                     globalOptions);
    }

    /**
     * Set the modified date of the next file to be written. The next call
     * to writeFile will use this date.
     * @param modifiedDate the date the file should be marked as modified
     */
    public void setNextFileDate(Date modifiedDate) {
        this.modifiedDate = modifiedDate;
    }

    /**
     * Get the modified date for the next file.
     * @return the date and then null the instance variable.
     */
    public Date getNextFileDate() {
        //
        // We null the instance variable so that future calls will not
        // retrieve a date specified for a previous file
        //
        Date copy = modifiedDate;
        modifiedDate = null;
        return copy;
    }

    /**
     * Get the Entry for the specified file, if one exists.
     * @param f the file
     * @throws IOException if the Entries file cannot be read
     */
    public Entry getEntry(File f)
            throws IOException {
        return adminHandler.getEntry(f);
    }

    /**
     * Get the entries for a specified directory.
     * @param directory the directory for which to get the entries
     * @return an iterator of Entry objects
     */
    public Iterator getEntries(File directory)
            throws IOException {
        return adminHandler.getEntries(directory);
    }

    /**
     * Get the repository path for a given directory, for example in
     * the directory /home/project/foo/bar, the repository directory
     * might be /usr/cvs/foo/bar. The repository directory is commonly
     * stored in the file 
Repository
in the CVS directory on * the client (this is the case in the standard CVS command-line tool). * * If no
CVS/Repository
file was found, the specified directory, * the localpath are used to "guess" the repository path. * * @param directory the directory */ public String getRepositoryForDirectory(String directory) throws IOException { try { String repository = adminHandler.getRepositoryForDirectory( directory, getRepository()); return repository; } catch (IOException ex) { // an IOException is thrown, if the adminHandler can't detect the repository // by reading the CVS/Repository file, e.g. when checking out into a new directory try { directory = new File(directory).getCanonicalPath(); } catch (IOException ioex) {} directory = directory.replace('\\', '/'); while (directory.endsWith("/")) { // NOI18N directory = directory.substring(0, directory.length() - 1); } int localPathLength = getLocalPath().length(); String repository; if (directory.length() >= localPathLength) { repository = getRepository() + directory.substring(localPathLength); } else { // Asking for some folder upon the local working path repository = getRepository(); } return repository; } } /** * Set the Entry for the specified file. * @param file the file * @param entry the new entry * @throws IOException if an error occurs writing the details */ public void setEntry(File file, Entry entry) throws IOException { adminHandler.setEntry(file, entry); } /** * Remove the Entry for the specified file. * @param file the file whose entry is to be removed * @throws IOException if an error occurs writing the Entries file */ public void removeEntry(File file) throws IOException { adminHandler.removeEntry(file); } /** * Remove the specified file from the local disk. * @param pathname the full path to the file to remove * @throws IOException if an IO error occurs while removing the file */ public void removeLocalFile(String pathname) throws IOException { transmitFileHandler.removeLocalFile(pathname); } /** * Removes the specified file determined by pathName and repositoryName. * In this implementation the filename from repositoryPath is added * to the localpath (which doesn't have the filename in it) and that file is deleted. */ public void removeLocalFile(String pathName, String repositoryName) throws IOException { int ind = repositoryName.lastIndexOf('/'); if (ind <= 0) { return; } String fileName = repositoryName.substring(ind + 1); String localFile = pathName + fileName; File fileToDelete = new File(getLocalPath(), localFile); removeLocalFile(fileToDelete.getAbsolutePath()); removeEntry(fileToDelete); } /** * Rename the local file. * @param pathname the full path to the file to rename * @param newName the new name of the file (not the full path) * @throws IOException if an IO error occurs while renaming the file */ public void renameLocalFile(String pathname, String newName) throws IOException { transmitFileHandler.renameLocalFile(pathname, newName); } /** * Get the CVS event manager. This is generally called by response handlers * that want to fire events. * @return the eventManager */ public EventManager getEventManager() { return eventManager; } /** * Get the global options that are set to this client. * Individual commands can get the global options via this method. */ public GlobalOptions getGlobalOptions() { return globalOptions; } /** * Call this method to abort the current command. The command will be * aborted at the next suitable time */ public synchronized void abort() { abort = true; } /** * Get all the files contained within a given * directory that are known to CVS. * @param directory the directory to look in * @return a set of all files. */ public Set getAllFiles(File directory) throws IOException { return adminHandler.getAllFiles(directory); } public void setIgnoreFileFilter(IgnoreFileFilter ignoreFileFilter) { this.ignoreFileFilter = ignoreFileFilter; } public IgnoreFileFilter getIgnoreFileFilter() { return ignoreFileFilter; } public boolean shouldBeIgnored(File directory, String noneCvsFile) { if (ignoreFileFilter != null) { return ignoreFileFilter.shouldBeIgnored(directory, noneCvsFile); } return false; } /** * Checks for presence of CVS/Tag file and returns it's value. * @returns the value of CVS/Tag file for the specified directory * null if file doesn't exist */ public String getStickyTagForDirectory(File directory) { return adminHandler.getStickyTagForDirectory(directory); } /** * This method is called when a response for the ValidRequests request * is received. * @param requests A List of requests that is valid for this CVS server * separated by spaces. */ public void setValidRequests(String requests) { // We need to tokenize the requests and add it to our map StringTokenizer tokenizer = new StringTokenizer(requests); String token; while (tokenizer.hasMoreTokens()) { token = tokenizer.nextToken(); // we just add an object with the corresponding request // as the key. validRequests.put(token, this); } } private int fillInitialRequests(List requests) { int pos = 0; requests.add(pos++, new RootRequest(getRepository())); requests.add(pos++, new UseUnchangedRequest()); requests.add(pos++, new ValidRequestsRequest()); requests.add(pos++, new ValidResponsesRequest()); return pos; } /** This method is called by WrapperSendResponse for each wrapper setting sent * back by the CVS server * @param pattern A StringPattern indicating the pattern for which the * wrapper applies * @param option A KeywordSubstituionOption corresponding to the setting */ public void addWrapper(StringPattern pattern, KeywordSubstitutionOptions option) { if (wrappersMap == null) { throw new IllegalArgumentException("This method should be called "+ "by WrapperSendResponse only."); } wrappersMap.put(pattern, option); } /** Returns the wrappers map associated with the CVS server * The map is valid only after the connection is established */ public Map getWrappersMap() throws CommandException { if (wrappersMap == null) { wrappersMap = new HashMap(); ArrayList requests = new ArrayList(); requests.add(new WrapperSendRequest()); boolean isFirst = isFirstCommand(); try { processRequests(requests); } catch (Exception ex) { throw new CommandException(ex, "An error during obtaining server wrappers."); } finally { // Do not alter isFirstCommand property setIsFirstCommand(isFirst); } wrappersMap = Collections.unmodifiableMap(wrappersMap); } return wrappersMap; } }
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