多线程学习笔记(五)

时间 2019-11-17

标签多线程学习笔记栏目 Java 繁體版

原文原文链接

一 . suspend()与resume()方法的使用ide

建立MyThread类this

public class MyThread extends Thread {

            private long i = 0;

            public long getI() {
                return i;
            }

            public void setI(long i) {
                this.i = i;
            }

            @Override
            public void run() {
                while (true) {
                    i++;
                }
            }
        }

建立调用类:线程

public class Test {
            public static void main(String[] args) {
                try {
                    MyThread myThread = new MyThread();
                    myThread.start();
                    Thread.sleep(2000);

                    myThread.suspend();
                    System.out.println(" the value of i = " + myThread.getI() + "and the time is : " + System.currentTimeMillis());

                    Thread.sleep(5000);
                    System.out.println(" the value of i = " + myThread.getI() + "and the time is : " + System.currentTimeMillis());

                    myThread.resume();
                    Thread.sleep(5000);

                    myThread.suspend();
                    System.out.println(" the value of i = " + myThread.getI() + "and the time is : " + System.currentTimeMillis());

                    Thread.sleep(5000);
                    System.out.println(" the value of i = " + myThread.getI() + "and the time is : " + System.currentTimeMillis());
                } catch (Exception e) {
                    e.printStackTrace();
                }

            }
}

运行结果:对象

二 . suspend()与resume()的缺点get

1 . 独占同步

在使用suspend()与resume()方法时,若是使用不当,极易形成公共的同步对象的独占,使得其余线程没法访问公共同步对象io

2 . suspend()与resume()的缺点 --- 不一样步class