| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You 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 org.apache.zeppelin.interpreter; |
| |
| import static java.nio.file.StandardWatchEventKinds.ENTRY_CREATE; |
| import static java.nio.file.StandardWatchEventKinds.ENTRY_DELETE; |
| import static java.nio.file.StandardWatchEventKinds.ENTRY_MODIFY; |
| import static java.nio.file.StandardWatchEventKinds.OVERFLOW; |
| import java.io.File; |
| import java.io.IOException; |
| import java.nio.file.ClosedWatchServiceException; |
| import java.nio.file.FileSystems; |
| import java.nio.file.Path; |
| import java.nio.file.WatchEvent; |
| import java.nio.file.WatchKey; |
| import java.nio.file.WatchService; |
| import java.util.HashMap; |
| import java.util.LinkedList; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.concurrent.TimeUnit; |
| |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| /** |
| * Watch the change for the development mode support |
| */ |
| public class InterpreterOutputChangeWatcher extends Thread { |
| Logger logger = LoggerFactory.getLogger(InterpreterOutputChangeWatcher.class); |
| |
| private WatchService watcher; |
| private final List<File> watchFiles = new LinkedList<>(); |
| private final Map<WatchKey, File> watchKeys = new HashMap<>(); |
| private InterpreterOutputChangeListener listener; |
| private boolean stop; |
| |
| public InterpreterOutputChangeWatcher(InterpreterOutputChangeListener listener) |
| throws IOException { |
| watcher = FileSystems.getDefault().newWatchService(); |
| this.listener = listener; |
| } |
| |
| public void watch(File file) throws IOException { |
| String dirString; |
| if (file.isFile()) { |
| dirString = file.getParentFile().getAbsolutePath(); |
| } else { |
| throw new IOException(file.getName() + " is not a file"); |
| } |
| |
| if (dirString == null) { |
| dirString = "/"; |
| } |
| |
| Path dir = FileSystems.getDefault().getPath(dirString); |
| logger.info("watch " + dir); |
| WatchKey key = dir.register(watcher, ENTRY_CREATE, ENTRY_DELETE, ENTRY_MODIFY); |
| synchronized (watchKeys) { |
| watchKeys.put(key, new File(dirString)); |
| watchFiles.add(file); |
| } |
| } |
| |
| public void clear() { |
| synchronized (watchKeys) { |
| for (WatchKey key : watchKeys.keySet()) { |
| key.cancel(); |
| |
| } |
| watchKeys.clear(); |
| watchFiles.clear(); |
| } |
| } |
| |
| public void shutdown() throws IOException { |
| stop = true; |
| clear(); |
| watcher.close(); |
| } |
| |
| public void run() { |
| while (!stop) { |
| WatchKey key = null; |
| try { |
| key = watcher.poll(1, TimeUnit.SECONDS); |
| } catch (InterruptedException | ClosedWatchServiceException e) { |
| break; |
| } |
| |
| if (key == null) { |
| continue; |
| } |
| for (WatchEvent<?> event : key.pollEvents()) { |
| WatchEvent.Kind<?> kind = event.kind(); |
| if (kind == OVERFLOW) { |
| continue; |
| } |
| WatchEvent<Path> ev = (WatchEvent<Path>) event; |
| Path filename = ev.context(); |
| // search for filename |
| synchronized (watchKeys) { |
| for (File f : watchFiles) { |
| if (f.getName().compareTo(filename.toString()) == 0) { |
| File changedFile; |
| if (filename.isAbsolute()) { |
| changedFile = new File(filename.toString()); |
| } else { |
| changedFile = new File(watchKeys.get(key), filename.toString()); |
| } |
| logger.info("File change detected " + changedFile.getAbsolutePath()); |
| if (listener != null) { |
| listener.fileChanged(changedFile); |
| } |
| } |
| } |
| } |
| } |
| |
| boolean valid = key.reset(); |
| if (!valid) { |
| break; |
| } |
| } |
| } |
| } |