java 实现监控某目录文件变化

commons-io-2.3.jar 中，有实现文件监控的类，在org.apache.commons.io.monitor包下，

主要包括 observer ，listener，monitor 含义你懂得滴，典型观察者模式，直接上代码：

listener:

public class ZJPFileListener implements FileAlterationListener{

ZJPFileMonitor monitor = null;
@Override
public void onStart(FileAlterationObserver observer) {
//System.out.println("onStart");
}
@Override
public void onDirectoryCreate(File directory) {
System.out.println("onDirectoryCreate:" +  directory.getName());
}

@Override
public void onDirectoryChange(File directory) {
System.out.println("onDirectoryChange:" + directory.getName());
}

@Override
public void onDirectoryDelete(File directory) {
System.out.println("onDirectoryDelete:" + directory.getName());
}

@Override
public void onFileCreate(File file) {
System.out.println("onFileCreate:" + file.getName());
}

@Override
public void onFileChange(File file) {
System.out.println("onFileCreate : " + file.getName());
}

@Override
public void onFileDelete(File file) {
System.out.println("onFileDelete :" + file.getName());
}

@Override
public void onStop(FileAlterationObserver observer) {
//System.out.println("onStop");
}

}

monitor

public class ZJPFileMonitor {

FileAlterationMonitor monitor = null;
public ZJPFileMonitor(long interval) throws Exception {
monitor = new FileAlterationMonitor(interval);
}

public void monitor(String path, FileAlterationListener listener) {
FileAlterationObserver observer = new FileAlterationObserver(new File(path));
monitor.addObserver(observer);
observer.addListener(listener);
}
public void stop() throws Exception{
monitor.stop();
}
public void start() throws Exception {
monitor.start();
}
public static void main(String[] args) throws Exception {
ZJPFileMonitor m = new ZJPFileMonitor(5000);
m.monitor("E:\\filepath",new ZJPFileListener());
m.start();
}

启动后，每5秒扫描指定路径下文件的变化，很方便