package de.pixart.messenger.utils; import android.os.FileObserver; import java.io.File; import java.util.ArrayList; import java.util.List; import java.util.Stack; /** * Copyright (C) 2012 Bartek Przybylski * Copyright (C) 2015 ownCloud Inc. * Copyright (C) 2016 Daniel Gultsch */ public abstract class ConversationsFileObserver { private final String path; private final List mObservers = new ArrayList<>(); public ConversationsFileObserver(String path) { this.path = path; } public synchronized void startWatching() { Stack stack = new Stack<>(); stack.push(path); while (!stack.empty()) { String parent = stack.pop(); mObservers.add(new SingleFileObserver(parent, FileObserver.DELETE | FileObserver.MOVED_FROM)); final File path = new File(parent); final File[] files = path.listFiles(); if (files == null) { continue; } for (File file : files) { if (file.isDirectory() && file.getName().charAt(0) != '.') { final String currentPath = file.getAbsolutePath(); if (depth(file) <= 8 && !stack.contains(currentPath) && !observing(currentPath)) { stack.push(currentPath); } } } } for (FileObserver observer : mObservers) { observer.startWatching(); } } private static int depth(File file) { int depth = 0; while ((file = file.getParentFile()) != null) { depth++; } return depth; } private boolean observing(String path) { for (SingleFileObserver observer : mObservers) { if (path.equals(observer.path)) { return true; } } return false; } public synchronized void stopWatching() { for (FileObserver observer : mObservers) { observer.stopWatching(); } mObservers.clear(); } abstract public void onEvent(int event, String path); private class SingleFileObserver extends FileObserver { private final String path; public SingleFileObserver(String path, int mask) { super(path, mask); this.path = path; } @Override public void onEvent(int event, String filename) { ConversationsFileObserver.this.onEvent(event, path + '/' + filename); } } }