求高手帮我解惑一下concurrentHashMap的问题

Question

import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;

public class ConcurrentHashMapTest {

private static final ConcurrentMap<String, String> factory = new ConcurrentHashMap<String, String>();

public static void main(String[] args) {
    for(int i=0;i<10;i++){
        new Thread(i+""){
            public void run(){
                String tf = factory.get("wang");
                if (tf == null) {
                    try {
                        Thread.sleep((int)(Math.random()*1000));
                        factory.put("wang", this.getName());
                        Thread.sleep((int)(Math.random()*1000));
                    } catch (Throwable e) {
                        e.printStackTrace();
                    }
                }
                System.out.println(this.getName()+"_"+factory.get("wang"));
            }
        }.start();
    }
}

}

上面这段代码中concurrentHashMap好像没起到作用，有高手帮忙解惑下吗

Answer 1

高手呢，在线等高手，顶顶