| /* |
| * Copyright (C) 2006 The Android Open Source Project |
| * |
| * Licensed 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 android.os; |
| |
| import android.util.Log; |
| |
| import com.android.internal.os.RuntimeInit; |
| |
| import java.lang.ref.WeakReference; |
| import java.util.ArrayList; |
| import java.util.HashMap; |
| |
| public abstract class FileObserver { |
| public static final int ACCESS = 0x00000001; /* File was accessed */ |
| public static final int MODIFY = 0x00000002; /* File was modified */ |
| public static final int ATTRIB = 0x00000004; /* Metadata changed */ |
| public static final int CLOSE_WRITE = 0x00000008; /* Writtable file was closed */ |
| public static final int CLOSE_NOWRITE = 0x00000010; /* Unwrittable file closed */ |
| public static final int OPEN = 0x00000020; /* File was opened */ |
| public static final int MOVED_FROM = 0x00000040; /* File was moved from X */ |
| public static final int MOVED_TO = 0x00000080; /* File was moved to Y */ |
| public static final int CREATE = 0x00000100; /* Subfile was created */ |
| public static final int DELETE = 0x00000200; /* Subfile was deleted */ |
| public static final int DELETE_SELF = 0x00000400; /* Self was deleted */ |
| public static final int MOVE_SELF = 0x00000800; /* Self was moved */ |
| public static final int ALL_EVENTS = ACCESS | MODIFY | ATTRIB | CLOSE_WRITE |
| | CLOSE_NOWRITE | OPEN | MOVED_FROM | MOVED_TO | DELETE | CREATE |
| | DELETE_SELF | MOVE_SELF; |
| |
| private static final String LOG_TAG = "FileObserver"; |
| |
| private static class ObserverThread extends Thread { |
| private HashMap<Integer, WeakReference> m_observers = new HashMap<Integer, WeakReference>(); |
| private int m_fd; |
| |
| public ObserverThread() { |
| super("FileObserver"); |
| m_fd = init(); |
| } |
| |
| public void run() { |
| observe(m_fd); |
| } |
| |
| public int startWatching(String path, int mask, FileObserver observer) { |
| int wfd = startWatching(m_fd, path, mask); |
| |
| Integer i = new Integer(wfd); |
| if (wfd >= 0) { |
| synchronized (m_observers) { |
| m_observers.put(i, new WeakReference(observer)); |
| } |
| } |
| |
| return i; |
| } |
| |
| public void stopWatching(int descriptor) { |
| stopWatching(m_fd, descriptor); |
| } |
| |
| public void onEvent(int wfd, int mask, String path) { |
| // look up our observer, fixing up the map if necessary... |
| FileObserver observer; |
| |
| synchronized (m_observers) { |
| WeakReference weak = m_observers.get(wfd); |
| observer = (FileObserver) weak.get(); |
| if (observer == null) { |
| m_observers.remove(wfd); |
| } |
| } |
| |
| // ...then call out to the observer without the sync lock held |
| if (observer != null) { |
| try { |
| observer.onEvent(mask, path); |
| } catch (Throwable throwable) { |
| Log.e(LOG_TAG, "Unhandled throwable " + throwable.toString() + |
| " (returned by observer " + observer + ")", throwable); |
| RuntimeInit.crash("FileObserver", throwable); |
| } |
| } |
| } |
| |
| private native int init(); |
| private native void observe(int fd); |
| private native int startWatching(int fd, String path, int mask); |
| private native void stopWatching(int fd, int wfd); |
| } |
| |
| private static ObserverThread s_observerThread; |
| |
| static { |
| s_observerThread = new ObserverThread(); |
| s_observerThread.start(); |
| } |
| |
| // instance |
| private String m_path; |
| private Integer m_descriptor; |
| private int m_mask; |
| |
| public FileObserver(String path) { |
| this(path, ALL_EVENTS); |
| } |
| |
| public FileObserver(String path, int mask) { |
| m_path = path; |
| m_mask = mask; |
| m_descriptor = -1; |
| } |
| |
| protected void finalize() { |
| stopWatching(); |
| } |
| |
| public void startWatching() { |
| if (m_descriptor < 0) { |
| m_descriptor = s_observerThread.startWatching(m_path, m_mask, this); |
| } |
| } |
| |
| public void stopWatching() { |
| if (m_descriptor >= 0) { |
| s_observerThread.stopWatching(m_descriptor); |
| m_descriptor = -1; |
| } |
| } |
| |
| public abstract void onEvent(int event, String path); |
| } |