概述

tryLock(long time, TimeUnit unit)方法和tryLock()方法是類似的，只不過區別在于這個方法在拿不到鎖時會等待一定的時間，在時間期限之內如果還拿不到鎖，就返回false。如果一開始拿到鎖或者在等待期間內拿到了鎖，則返回true。

代碼

@Testpublic void testTryLock2() throws Exception {Lock lock = new ReentrantLock();new Thread() {@Overridepublic void run() {String tName = Thread.currentThread().getName();try {//獲取不到鎖，就等7秒，如果7秒后還是獲取不到就返回falseif (lock.tryLock(7000, TimeUnit.MILLISECONDS)) {System.out.println(tName + "獲取到鎖！");} else {System.out.println(tName + "獲取不到鎖！");return;}} catch (Exception e) {e.printStackTrace();}try {for (int i = 0; i < 5; i++) {System.out.println(tName + ":" + i);}Thread.sleep(3000);} catch (Exception e) {System.out.println(tName + "出錯了！！！");} finally {System.out.println(tName + "釋放鎖！！");lock.unlock();}}}.start();new Thread() {@Overridepublic void run() {String tName = Thread.currentThread().getName();try {//獲取不到鎖，就等7秒，如果7秒后還是獲取不到就返回falseif (lock.tryLock(7000, TimeUnit.MILLISECONDS)) {System.out.println(tName + "獲取到鎖！");} else {System.out.println(tName + "獲取不到鎖！");return;}} catch (Exception e) {e.printStackTrace();}try {for (int i = 0; i < 5; i++) {System.out.println(tName + ":" + i);}} catch (Exception e) {System.out.println(tName + "出錯了！！！");} finally {System.out.println(tName + "釋放鎖！！");lock.unlock();}}}.start();Thread.sleep(15000);//主線程}

運行結果

Thread-0獲取到鎖！
Thread-0:0
Thread-0:1
Thread-0:2
Thread-0:3
Thread-0:4
Thread-0睡覺......
Thread-0醒了......
Thread-0釋放鎖！！
Thread-1獲取到鎖！
Thread-1:0
Thread-1:1
Thread-1:2
Thread-1:3
Thread-1:4
Thread-1釋放鎖！！