关于线程的缓存刷新

public class test2 {

    private static boolean kaiguan =true;
    private static void go(){
        new Thread(()->{
            while (kaiguan){
            }

            System.out.println("事情做完了");
        }).start();
        new Thread(()->{
            try {
                Thread.sleep(1000*3);
                kaiguan=false;
            }catch (InterruptedException e){
                e.printStackTrace();
            }
        }).start();
    }

    public static void main(String[] args) {
        go();
    }


}

In essence, releasing a lock forces a flush of all writes from working memory employed by the thread, and acquiring a lock forces a (re)load of the values of accessible fields. While lock actions provide exclusion only for the operations performed within a synchronized method or block, these memory effects are defined to cover all fields used by the thread performing the action.

    public void println() {
        newLine();
    }
    
        private void newLine() {
        try {
            synchronized (this) {
                ensureOpen();
                textOut.newLine();
                textOut.flushBuffer();
                charOut.flushBuffer();
                if (autoFlush)
                    out.flush();
            }
        }
        catch (InterruptedIOException x) {
            Thread.currentThread().interrupt();
        }
        catch (IOException x) {
            trouble = true;
        }
    }
    

Thread.yield();
与
Thread.sleep(0);

  public static Unsafe getUnsafe() {
        try {
            Field field = Unsafe.class.getDeclaredField("theUnsafe");
            field.setAccessible(true);
            return (Unsafe) field.get(null);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

public  class TestTempOne {
  final int num; //设为final；
    TestTempOne(int num){
        this.num=num;
    }

}

private static void go(){
        new Thread(()->{
            while (kaiguan){
//                new TestTempOne(0);  //跳出循环
//               new String("a");      //跳出循环
//                new Integer(0);      //死循环
//                new Integer(129); //死循环
                new Integer(100000000); //死循环
            }