Thread Special Storage 模式

Thread Special Storage 模式是一种即使只有一个入口，也会为每一个线程分配特有的存储空间的模式。

实际案例

类信息概览：

类名 说明
Main.java 方法的总入口
LogInterface.java 日志接口
ThreadSpecialLog.java 每个线程分配特有存储空间的类
ClientThread.java 客户端
Log.java 创建日志的类

定义

  • LogInterface.java
package com.github.houbb.thread.learn.easy.learn.threadSpecialStorage;

/**
 * 2018/2/4
 *
 * @author houbinbin
 * @version 1.0
 * @since 1.7
 */
public interface LogInterface {

    void printLog(String log);

    void closeLog();

}
  • ThreadSpecialLog.java
package com.github.houbb.thread.learn.easy.learn.threadSpecialStorage;

import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;

/**
 * 2018/2/4
 *
 * @author houbinbin
 * @version 1.0
 * @since 1.7
 */
public class ThreadSpecialLog implements LogInterface{

    private PrintWriter printWriter = null;

    public ThreadSpecialLog(final String fileName) {
        try {
            printWriter = new PrintWriter(new FileWriter(fileName));
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    @Override
    public void printLog(String log) {
        printWriter.println(log);
    }

    @Override
    public void closeLog() {
        printWriter.print("================= END OF LOG =================");
        printWriter.close();
    }

}
  • ClientThread.java
package com.github.houbb.thread.learn.easy.learn.threadSpecialStorage;

/**
 * 2018/2/4
 *
 * @author houbinbin
 * @version 1.0
 * @since 1.7
 */
public class ClientThread extends Thread {

    public ClientThread(String threadName) {
        super(threadName);
    }

    @Override
    public void run() {
        System.out.println("MAIN BEGIN...");
        for(int i = 0; i < 10; i++) {
            Log.printLog("log-"+i);
        }
        Log.closeLog();
        System.out.println("MAIN END...");
    }

}
  • Log.java
package com.github.houbb.thread.learn.easy.learn.threadSpecialStorage;

/**
 * 2018/2/4
 *
 * @author houbinbin
 * @version 1.0
 * @since 1.7
 */
public class Log {

    private static final ThreadLocal<ThreadSpecialLog> tsLogCollection = new ThreadLocal<>();

    public static void printLog(String log) {
        getTsLog().printLog(log);
    }

    public static void closeLog() {
        getTsLog().closeLog();
    }

    private static LogInterface getTsLog() {
        ThreadSpecialLog threadSpecialLog = tsLogCollection.get();
        if(null == threadSpecialLog) {
            String fileName = Thread.currentThread().getName()+"-log.txt";
            threadSpecialLog = new ThreadSpecialLog(fileName);
            tsLogCollection.set(threadSpecialLog);
            return threadSpecialLog;
        }
        return threadSpecialLog;
    }

}

测试

  • Main.java
package com.github.houbb.thread.learn.easy.learn.threadSpecialStorage;

/**
 * 2018/2/4
 *
 * @author houbinbin
 * @version 1.0
 * @since 1.7
 */
public class Main {

    public static void main(String[] args) {
        new ClientThread("One").start();
        new ClientThread("Two").start();
        new ClientThread("Three").start();
    }

}
  • 测试结果
MAIN BEGIN...
MAIN BEGIN...
MAIN BEGIN...
MAIN END...
MAIN END...
MAIN END...

实现方式

UML & Code

UML

UML 图示如下

Code

代码地址

Thread Special Storage

系列导航

多线程系列导航