import java.io.*;
import java.nio.channels.*;
/**
* 锁住文件（不让其它线程或进程修改）
*
* @author kingfish
*/
public class LockFile {
public LockFile() {
}
public static void main(String[] args) throws Exception {
RandomAccessFile raf = new RandomAccessFile(new File("c:\\test.txt"), "rw");
FileChannel fc = raf.getChannel();
FileLock fl = fc.tryLock();
if (fl.isValid()) {
System.out.println("get the lock!");
//测试线程
new Thread() {
public void run() {
while (true) {
try {
Thread.sleep(100);
FileReader fr = new FileReader(new File("c:\\test.txt"));
int c;
while ( (c = fr.read()) != -1) {
System.out.println( (char) c);
}
fr.close();
break;
}
catch (Exception e) {
System.out.println(e);
}
}
}
}.start();
//模拟其它操作的耗时：比如用notepad打开无法修改。但是用程序来读写此文件都会异常
raf.write("kingfish(八百里秦川@龙城异客)".getBytes());
Thread.sleep(5000);
fl.release();
System.out.println("release the lock!");
}
raf.close();
}
}
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