技術標籤：多執行緒多執行緒javathread併發程式設計

package 物件及變數的併發訪問2;

/**
 * 方法內的變數為執行緒安全
 *
 *   非執行緒安全問題存在於例項變數中，對於方法內部的私有變數，則不會存在非執行緒
 *   安全問題，結果是“執行緒安全”的。
 *
 *   結果分析 ： 方法中的變數不存在非執行緒安全問題，永遠都是執行緒安全的，這是因為方法內部的變數具有私有特性。
 */

/**
 * 測試
 */
class HasSelfPrivateNumT211 {
    public void addI(String userName){
        try
 
 {
            int num=0;
            if(userName.equals("a")){
                num=100;
                System.out.println("a set over!");
                Thread.sleep(2000);
            }else {
                num=200;
                System.out.println("b set over!");
            }
 

            System.out.println(userName+"num="+num);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
}

class ThreadAT211 extends Thread{
    private HasSelfPrivateNumT211 numT2211;
    public ThreadAT211(HasSelfPrivateNumT211 numT2211){
        super
 
();
        this.numT2211=numT2211;
    }

    @Override
    public void run() {
        super.run();
        numT2211.addI("a");
    }
}

class ThreadBT211 extends Thread{
    private HasSelfPrivateNumT211 numT2211;
    public ThreadBT211(HasSelfPrivateNumT211 numT2211){
        super();
        this.numT2211=numT2211;
    }

    @Override
    public void run() {
        super.run();
        numT2211.addI("b");
    }
}

/**
 * 執行
 */

class RunT211 {
    public RunT211(){
        HasSelfPrivateNumT211 numT2211=new HasSelfPrivateNumT211();

        ThreadAT211 at2211=new ThreadAT211(numT2211);
        at2211.start();

        ThreadBT211 bt2211=new ThreadBT211(numT2211);
        bt2211.start();
    }
}
public class T2101 {
    public static void main(String[] args) {
        RunT211 runT211 =new RunT211();
    }
}