lock()：若lock被thread A取得，thread B会进入block状态，直到取得lock；
tryLock()：若当下不能取得lock，thread就会放弃，可以设置一个超时时间参数，等待多久获取不到锁就放弃；
lockInterruptibly()：跟lock()情況一下，但是thread B可以通过interrupt中断，放弃继续等待锁
lock 与 lockInterruptibly比较区别在于：lock 优先考虑获取锁，待获取锁成功后，才响应中断，而lockInterruptibly 优先考虑响应中断
ReentrantLock.lockInterruptibly允许在等待时由其它线程调用等待线程的Thread.interrupt方法来中断等待线程的等待而直接返回，这时不用获取锁，而会抛出一个InterruptedException
ReentrantLock.lock方法不允许Thread.interrupt中断,即使检测到Thread.isInterrupted,一样会继续尝试获取锁，失败则继续休眠。只是在最后获取锁成功后再把当前线程置为interrupted状态,然后再中断线程
public class LockDemo {
private ReentrantLock lock = new ReentrantLock();
public static void main(String[] args) throws InterruptedException {
final LockDemo lockDemo = new LockDemo();
Thread threada = new Thread("Thread A") {
@Override
public void run() {
lockDemo.doSomeThing3(Thread.currentThread());
}
};
threada.start();
Thread threadb = new Thread("Thread B") {
@Override
public void run() {
lockDemo.doSomeThing3(Thread.currentThread());
}
};
threadb.start();
//threadb.interrupt();
}
public void doSomeThing1(Thread thread) {
lock.lock();
try {
System.out.println(thread.getName() + "得到了锁.");
Thread.sleep();
} catch (Exception e) {
e.printStackTrace();
} finally {
System.out.println(thread.getName() + "释放了锁.");
lock.unlock();
}
}
public void doSomeThing2(Thread thread) {
if (lock.tryLock()) {
try {
System.out.println(thread.getName() + "得到了锁.");
Thread.sleep();
} catch (Exception e) {
e.printStackTrace();
} finally {
System.out.println(thread.getName() + "释放了锁.");
lock.unlock();
}
} else {
System.out.println(thread.getName() + "获取锁失败.");
}
}
public void doSomeThing3(Thread thread) {
try {
lock.lockInterruptibly();
System.out.println(thread.getName() + " 得到了锁.");
Thread.sleep();
} catch (InterruptedException e1) {
e1.printStackTrace();
System.out.println(thread.getName() + " interrupted.");
} finally {
System.out.println(thread.getName() + " 释放了锁.");
lock.unlock();
}
}
}