Balking 模式
Balking 模式是指如果不适合执行这个操作，或者没必要执行这个操作，就停止操作，直接返回。
实际案例
类信息概览：
| 类名 | 说明 |
|---|---|
| Main.java | 方法的总入口 |
| SaveThread.java | 保存线程 |
| Data.java | 数据 |
| ChangeThread.java | 变更线程 |
定义
- 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();
}
}
}
}
测试
- 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();
}
}
- 测试结果
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
实现方式
UML & Code
UML
Code
代码地址
