Easy to learn multithreading-05-Balking mode

content

Balking mode

Balking mode means that if it is not suitable to perform this operation, or if it is unnecessary to perform this operation, stop the operation and return directly.

actual case

Overview of class information:

class name	illustrate
Main.java	general entry for the method
SaveThread.java	save thread
Data.java	data
ChangeThread.java	change thread

definition

• SaveThread.java

package com.github.houbb.thread.learn.easy.learn.balking;

public class SaveThread extends Thread {

    private String name;

    private final Data data;

    public SaveThread(String name, Data data) {
        super(name);
        this.data = data;
    }

    @Override
    public void run() {
        while(true) {
            try {
                Thread.sleep(1000);
                data.save();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }
}

• Data.java

package com.github.houbb.thread.learn.easy.learn.balking;

public class Data {
    /**
     * 文件名称
     */
    private final String fileName;

    /**
     * 是否变化标识
     */
    private boolean changeFlag;

    /**
     * 内容
     */
    private String content;

    public Data(String fileName, String content) {
        this.fileName = fileName;
        this.content = content;
    }

    public synchronized void change(final String content) {
        this.content = content;
        this.changeFlag = true;
    }

    public synchronized void save() {
        //balking   没有变化直接返回
        if(!changeFlag) {
            return;
        }

        doSave();
        this.changeFlag = false;
    }

    private void doSave() {
        System.out.println(Thread.currentThread().getName() + " calls do save content: "+content+" tO file " + fileName);
    }

}

• ChangeThread.java

package com.github.houbb.thread.learn.easy.learn.balking;

import java.util.Random;

public class ChangeThread extends Thread {

    private String name;

    private final Data data;

    public ChangeThread(String name, Data data) {
        super(name);
        this.data = data;
    }

    /**
     * 固定 1S 保存一次数据
     */
    @Override
    public void run() {
        Random random = new Random(1000L);
        while(true) {
            try {
                int value = random.nextInt(1000);
                data.change(String.valueOf(value));
                Thread.sleep(value);
                data.save();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }
}

test

• Main.java

package com.github.houbb.thread.learn.easy.learn.balking;

public class Main {

    public static void main(String[] args) {
        Data data = new Data("124.txt", "");
        new ChangeThread("CHANGE", data).start();
        new SaveThread("SAVE", data).start();
    }

}

• Test Results

CHANGE calls do save content: 487 tO file 124.txt
SAVE calls do save content: 935 tO file 124.txt
SAVE calls do save content: 676 tO file 124.txt
CHANGE calls do save content: 124 tO file 124.txt
SAVE calls do save content: 792 tO file 124.txt
CHANGE calls do save content: 349 tO file 124.txt
SAVE calls do save content: 641 tO file 124.txt

Method to realize

UML & Code

UML

The UML diagram is as follows

Code

code address

Balking

Series Navigation

Multithreaded series navigation