为什么输出都是null?
public class MyJava{
public static void main(String[] args){
String[] strs=new String[2];
MyThread_A t1=new MyThread_A(strs);
MyThread_B t2=new MyThread_B(strs);
t1.start();
t2.start();
for(String s:strs) System.out.println(s); //打印每个线程收集的数据
}
}
class MyThread_A extends Thread{
String[] strs;
public MyThread_A(String[] strs){
this.strs=strs;
}
public void run(){
String s=null; //计算机strs[0]的值
s="a";
strs[0]=s;
}
}
class MyThread_B extends Thread{
String[] strs;
public MyThread_B(String[] strs){
this.strs=strs;
}
public void run(){
String s=null;
s="b"; //计算机strs[1]的值
strs[1]=s;
}
}