com.kaka.util.FileWatcher Maven / Gradle / Ivy
package com.kaka.util;
import java.io.File;
import java.io.IOException;
import java.nio.file.FileSystems;
import java.nio.file.Path;
import java.nio.file.Paths;
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.nio.file.WatchEvent;
import java.nio.file.WatchKey;
import java.nio.file.WatchService;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;
/**
* 文件变动监控
*
* @author zkpursuit
*/
public class FileWatcher implements Runnable {
private final WatchService watcher = FileSystems.getDefault().newWatchService();
private boolean watchFlag;
private final WatchCallBack callback;
/**
* 构造方法
*
* @param watchDir 监控目录
* @param descendants 是否监控目录下的子孙目录
* @param callback 文件监控回调
* @throws IOException IO流异常
*/
public FileWatcher(String watchDir, boolean descendants, WatchCallBack callback) throws IOException {
this.callback = callback;
if (descendants) {
File dir = new File(watchDir);
List dirs = FileUtils.getDirectories(dir, true);
for (File file : dirs) {
String absPath = file.getAbsolutePath();
Path path = Paths.get(absPath);
path.register(watcher, ENTRY_CREATE, OVERFLOW, ENTRY_MODIFY, ENTRY_DELETE);
}
} else {
Path path = Paths.get(watchDir);
path.register(watcher, ENTRY_CREATE, OVERFLOW, ENTRY_MODIFY, ENTRY_DELETE);
}
watchFlag = true;
}
/**
* 停止文件监控
*/
public void stop() {
watchFlag = false;
}
public void close() throws IOException {
stop();
watcher.close();
}
@Override
public void run() {
while (watchFlag) {
if (watcher == null) {
return;
}
WatchKey signal;
try {
signal = watcher.take();
Path watchDirPath = (Path) signal.watchable();
signal.pollEvents().forEach((WatchEvent> event) -> {
WatchEvent.Kind> kind = event.kind();
Path fileNamePath = (Path) event.context();
if (callback != null) {
callback.call(kind, watchDirPath, fileNamePath);
}
});
signal.reset();
} catch (InterruptedException ex) {
Logger.getLogger(FileWatcher.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
/**
* 文件变动回调
*/
public interface WatchCallBack {
/**
* 监控文件变动的回调
*
* @param kind 文件变动的类型
* @param watchDirPath 变化的目录
* @param fileNamePath 变化的文件
*/
void call(WatchEvent.Kind> kind, Path watchDirPath, Path fileNamePath);
}
}