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/*
 * VFSManager.java - Main class of virtual filesystem
 * :tabSize=8:indentSize=8:noTabs=false:
 * :folding=explicit:collapseFolds=1:
 *
 * Copyright (C) 2000, 2003 Slava Pestov
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */

package org.gjt.sp.jedit.io;

//{{{ Imports
import javax.swing.JOptionPane;
import javax.swing.SwingUtilities;
import java.awt.Component;
import java.awt.Frame;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.LinkedList;
import java.util.List;
import java.util.Vector;
import org.gjt.sp.jedit.gui.ErrorListDialog;
import org.gjt.sp.jedit.msg.VFSUpdate;
import org.gjt.sp.jedit.*;
import org.gjt.sp.util.Log;
import org.gjt.sp.util.WorkThreadPool;
//}}}

/**
 * jEdit's virtual filesystem allows it to transparently edit files
 * stored elsewhere than the local filesystem, for example on an FTP
 * site. See the {@link VFS} class for implementation details.

* * Note that most of the jEdit API is not thread-safe, so special care * must be taken when making jEdit API calls. Also, it is not safe to * call SwingUtilities.invokeAndWait() from a work request; * it can cause a deadlock if the given runnable then later calls * {@link #waitForRequests()}. * * @author Slava Pestov * @version $Id: VFSManager.java,v 1.15 2004/05/10 03:21:11 spestov Exp $ */ public class VFSManager { /** * The service type. See {@link org.gjt.sp.jedit.ServiceManager}. * @since jEdit 4.2pre1 */ public static final String SERVICE = "org.gjt.sp.jedit.io.VFS"; //{{{ init() method /** * Do not call. */ public static void init() { int count = jEdit.getIntegerProperty("ioThreadCount",4); ioThreadPool = new WorkThreadPool("jEdit I/O",count); JARClassLoader classLoader = new JARClassLoader(); for(int i = 0; i < ioThreadPool.getThreadCount(); i++) { ioThreadPool.getThread(i).setContextClassLoader( classLoader); } } //}}} //{{{ start() method /** * Do not call. */ public static void start() { ioThreadPool.start(); } //}}} //{{{ VFS methods //{{{ getFileVFS() method /** * Returns the local filesystem VFS. * @since jEdit 2.5pre1 */ public static VFS getFileVFS() { return fileVFS; } //}}} //{{{ getUrlVFS() method /** * Returns the URL VFS. * @since jEdit 2.5pre1 */ public static VFS getUrlVFS() { return urlVFS; } //}}} //{{{ getVFSByName() method /** * @deprecated Use getVFSForProtocol() instead. */ public static VFS getVFSByName(String name) { // in new api, protocol always equals name VFS vfs = (VFS)ServiceManager.getService(SERVICE,name); if(vfs == null) return (VFS)vfsHash.get(name); else return vfs; } //}}} //{{{ getVFSForProtocol() method /** * Returns the VFS for the specified protocol. * @param protocol The protocol * @since jEdit 2.5pre1 */ public static VFS getVFSForProtocol(String protocol) { if(protocol.equals("file")) return fileVFS; else { VFS vfs = (VFS)ServiceManager.getService(SERVICE,protocol); if(vfs == null) vfs = (VFS)protocolHash.get(protocol); if(vfs != null) return vfs; else return urlVFS; } } //}}} //{{{ getVFSForPath() method /** * Returns the VFS for the specified path. * @param path The path * @since jEdit 2.6pre4 */ public static VFS getVFSForPath(String path) { if(MiscUtilities.isURL(path)) return getVFSForProtocol(MiscUtilities.getProtocolOfURL(path)); else return fileVFS; } //}}} //{{{ registerVFS() method /** * @deprecated Write a services.xml file instead; * see {@link org.gjt.sp.jedit.ServiceManager}. */ public static void registerVFS(String protocol, VFS vfs) { Log.log(Log.DEBUG,VFSManager.class,"Registered " + vfs.getName() + " filesystem for " + protocol + " protocol"); vfsHash.put(vfs.getName(),vfs); protocolHash.put(protocol,vfs); } //}}} //{{{ getFilesystems() method /** * @deprecated Use getVFSs() instead. */ public static Enumeration getFilesystems() { return vfsHash.elements(); } //}}} //{{{ getVFSs() method /** * Returns a list of all registered filesystems. * @since jEdit 4.2pre1 */ public static String[] getVFSs() { // the sooner ppl move to the new api, the less we'll need // crap like this List returnValue = new LinkedList(); String[] newAPI = ServiceManager.getServiceNames(SERVICE); if(newAPI != null) { for(int i = 0; i < newAPI.length; i++) { returnValue.add(newAPI[i]); } } Enumeration oldAPI = vfsHash.keys(); while(oldAPI.hasMoreElements()) returnValue.add(oldAPI.nextElement()); return (String[])returnValue.toArray(new String[ returnValue.size()]); } //}}} //}}} //{{{ I/O request methods //{{{ getIOThreadPool() method /** * Returns the I/O thread pool. */ public static WorkThreadPool getIOThreadPool() { return ioThreadPool; } //}}} //{{{ waitForRequests() method /** * Returns when all pending requests are complete. * @since jEdit 2.5pre1 */ public static void waitForRequests() { ioThreadPool.waitForRequests(); } //}}} //{{{ errorOccurred() method /** * Returns if the last request caused an error. */ public static boolean errorOccurred() { return error; } //}}} //{{{ getRequestCount() method /** * Returns the number of pending I/O requests. */ public static int getRequestCount() { return ioThreadPool.getRequestCount(); } //}}} //{{{ runInAWTThread() method /** * Executes the specified runnable in the AWT thread once all * pending I/O requests are complete. * @since jEdit 2.5pre1 */ public static void runInAWTThread(Runnable run) { ioThreadPool.addWorkRequest(run,true); } //}}} //{{{ runInWorkThread() method /** * Executes the specified runnable in one of the I/O threads. * @since jEdit 2.6pre2 */ public static void runInWorkThread(Runnable run) { ioThreadPool.addWorkRequest(run,false); } //}}} //}}} //{{{ error() method /** * @deprecated Call the other error() method instead. */ public static void error(final Component comp, final String error, final Object[] args) { // if we are already in the AWT thread, take a shortcut if(SwingUtilities.isEventDispatchThread()) { GUIUtilities.error(comp,error,args); return; } // the 'error' chicanery ensures that stuff like: // VFSManager.waitForRequests() // if(VFSManager.errorOccurred()) // ... // will work (because the below runnable will only be // executed in the next event) VFSManager.error = true; runInAWTThread(new Runnable() { public void run() { VFSManager.error = false; if(comp == null || !comp.isShowing()) GUIUtilities.error(null,error,args); else GUIUtilities.error(comp,error,args); } }); } //}}} //{{{ error() method /** * Reports an I/O error. * * @param comp The component * @param path The path name that caused the error * @param messageProp The error message property name * @param args Positional parameters * @since jEdit 4.0pre3 */ public static void error(Component comp, final String path, String messageProp, Object[] args) { final Frame frame = JOptionPane.getFrameForComponent(comp); synchronized(errorLock) { error = true; errors.addElement(new ErrorListDialog.ErrorEntry( path,messageProp,args)); if(errors.size() == 1) { VFSManager.runInAWTThread(new Runnable() { public void run() { String caption = jEdit.getProperty( "ioerror.caption" + (errors.size() == 1 ? "-1" : ""),new Integer[] { new Integer(errors.size()) }); new ErrorListDialog( frame.isShowing() ? frame : jEdit.getFirstView(), jEdit.getProperty("ioerror.title"), caption,errors,false); errors.removeAllElements(); error = false; } }); } } } //}}} //{{{ sendVFSUpdate() method /** * Sends a VFS update message. * @param vfs The VFS * @param path The path that changed * @param parent True if an update should be sent for the path's * parent too * @since jEdit 2.6pre4 */ public static void sendVFSUpdate(VFS vfs, String path, boolean parent) { if(parent) { sendVFSUpdate(vfs,vfs.getParentOfPath(path),false); sendVFSUpdate(vfs,path,false); } else { // have to do this hack until VFSPath class is written if(path.length() != 1 && (path.endsWith("/") || path.endsWith(java.io.File.separator))) path = path.substring(0,path.length() - 1); synchronized(vfsUpdateLock) { for(int i = 0; i < vfsUpdates.size(); i++) { VFSUpdate msg = (VFSUpdate)vfsUpdates .get(i); if(msg.getPath().equals(path)) { // don't send two updates // for the same path return; } } vfsUpdates.add(new VFSUpdate(path)); if(vfsUpdates.size() == 1) { // we were the first to add an update; // add update sending runnable to AWT // thread VFSManager.runInAWTThread(new SendVFSUpdatesSafely()); } } } } //}}} //{{{ SendVFSUpdatesSafely class static class SendVFSUpdatesSafely implements Runnable { public void run() { synchronized(vfsUpdateLock) { // the vfs browser has what you might call // a design flaw, it doesn't update properly // unless the vfs update for a parent arrives // before any updates for the children. sorting // the list alphanumerically guarantees this. Collections.sort(vfsUpdates, new MiscUtilities.StringCompare() ); for(int i = 0; i < vfsUpdates.size(); i++) { EditBus.send((VFSUpdate)vfsUpdates.get(i)); } vfsUpdates.clear(); } } } //}}} //{{{ Private members //{{{ Static variables private static WorkThreadPool ioThreadPool; private static VFS fileVFS; private static VFS urlVFS; private static Hashtable vfsHash; private static Hashtable protocolHash; private static boolean error; private static Object errorLock; private static Vector errors; private static Object vfsUpdateLock; private static List vfsUpdates; //}}} //{{{ Class initializer static { errorLock = new Object(); errors = new Vector(); fileVFS = new FileVFS(); urlVFS = new UrlVFS(); vfsHash = new Hashtable(); protocolHash = new Hashtable(); vfsUpdateLock = new Object(); vfsUpdates = new ArrayList(10); } //}}} private VFSManager() {} //}}} }

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