Question

我在线程中使用"\n"作为换行符，但它不起作用。我经历了很多建议使用的答案 System.getProperty("line.separator"); 但这对我也不起作用..

public static void main(String args[]) {

final ReentrantLock lock1 = new ReentrantLock();
final ReentrantLock lock2 = new ReentrantLock();

Runnable try1_2 = getRunnable(lock1, "lock 1", lock2, "lock 2");
Runnable try2_1 = getRunnable(lock2, "lock 2", lock1, "lock 1");

new Thread(try1_2).start();
new Thread(try2_1).start();

}

private Runnable getRunnable(final ReentrantLock lock1, final String lock1Name, final ReentrantLock lock2, final String lock2Name) {
    return new Runnable() {
        @Override
        public void run() {
            try {

                if (lock1.tryLock(1, TimeUnit.SECONDS)) {

                    System.out.println("1"+lock1Name + " acquired in thread " + Thread.currentThread().getName());
                    text_3.setText(text_3.getText() +"1"+lock1Name + " acquired in thread " + Thread.currentThread().getName());

                    if (lock2.tryLock(1, TimeUnit.SECONDS)) {

                        System.out.println("2"+lock2Name + " acquired in thread " + Thread.currentThread().getName());
                        text_3.setText(text_3.getText() + "\n"+"2"+lock2Name + " acquired in thread " + Thread.currentThread().getName());

                        Thread.sleep(2000);
                    } else {

                        System.out.println("3"+"Could not acquire "+lock2Name + " in thread " + Thread.currentThread().getName());
                        text_3.setText(text_3.getText() + "\n"+"3"+"Could not acquire "+lock2Name + " in thread " + Thread.currentThread().getName());

                        lock1.unlock();

                        System.out.println("4"+lock1Name + " released in thread " + Thread.currentThread());
                        text_3.setText(text_3.getText() + "\n"+"4"+lock1Name + " released in thread " + Thread.currentThread());

                    }
                } else {
                    System.out.println("5"+"Could not acquire " + lock1Name + " in thread " + Thread.currentThread());
                    text_3.setText(text_3.getText() + "\n"+"5"+"Could not acquire " + lock1Name + " in thread " + Thread.currentThread());
                }
            } catch (InterruptedException e) {

            } finally {

                if (lock1.isHeldByCurrentThread()) lock1.unlock();
                if (lock2.isHeldByCurrentThread()) lock2.unlock();
            }
        }
    };
}

输出如下：

1lock 2 acquired in thread thread-1 1lock 2 acquired in thread thread-0....

我希望如下：

1lock 2 acquired in thread thread-1 1lock 2 acquired in thread thread-0....

Answer 1

请使用，System.getProperty（“line.separator”）;像这样，

 String newLine = System.getProperty("line.separator");

 //then insert newLine variable as this :
 text_3.setText(text_3.getText() + newLine+ "2 " + lock2Name +
 "acquired in thread " + Thread.currentThread().getName());

Answer 2

您是否尝试将文字设为"<html> this is <br> test</html>"？

如何在java中换行

2 个答案: