作者doggingg (doggingg)
看板java
标题[问题] java多执行绪问题请教
时间Mon May 7 15:33:33 2012
我想自行练习写一个多执行绪，
让args吃两个参数-一个决定动态生成几个Thread-一个是整数N
把整数N平分给每个Thread去计算总和最後再把所有Thread算好的部分加总起来
但我的程式遇到一点问题，
我希望呼叫check方法时可以取得所有thread算完的总和，请问该怎麽做呢?????
public class Project {
/**
* @param args the command line arguments
*/
public static void main(String[] args) {
// TODO code application logic here
String temp1="";
String temp2="";
int ThreadNum=0;
int n=0;
temp1 = args[0];
temp2 = args[1];
ThreadNum = Integer.parseInt(temp1);
n = Integer.parseInt(temp2);
Show ba = new Show();
Counting[] p = new Counting[ThreadNum+1];
Thread[] t = new Thread[p.length];
int total =0;
for(int i=1;i<p.length;i++)
{
int m = (i-1)*(n/ThreadNum)+1;
int s = i*(n/ThreadNum);
String Name = "t["+i+"]";
p[i] = new Counting(ba,Name,m,s);
t[i] = new Thread(p[i]);
t[i].start();
System.out.println(ba.total);
}
//System.out.println();
//System.out.println("temp="+temp);
}
}
class Show
{
public static int total ;
public static int last =total;
public void save(int x)
{
total+=x;
//System.out.println("now total:"+total);
}
public void check()
{
System.out.println(total);
//return total;
}
}
class Counting implements Runnable
{
private int start;
private int end;
public int sum;
private String name;
Show ba;
public int temp=0;
Counting (Show ba,String n,int m,int s)
{
this.ba = ba;
name = n;
start = m;
end = s;
}
public synchronized void run()
{
System.out.println(name+"\tstarting");
for(int a = start;a<=end;a++)
{
sum+=a;
}
//System.out.println(t[0].current.getName());
//System.out.println(start+"\t"+end+"\t"+sum);
//System.out.println("-----------------");
ba.save(sum);
temp = sum;
//System.out.println(ba.check());
ba.check();
System.out.println(name+"\tover");
}
}
--
※ 发信站: 批踢踢实业坊(ptt.cc)
◆ From: 140.121.196.35
1F：推 swpoker:你在show那边做一个计数的就可以了 05/07 16:05
2F：→ doggingg:有阿，可是我要怎麽才能在所有THREAD执行完後再取结果值 05/07 16:16
3F：推 LaPass:丢个block卡住他，另外thing in java有讲另外一种，专门为 05/07 16:29
4F：推 LaPass:计算=>取值用的执行绪物件，不过我手边没书.... 05/07 16:32
5F：推 Chikei:CountDownLatch 05/07 16:36
6F：推 mars90226:wait()执行绪? 05/07 18:36
7F：→ doggingg:谢谢大家~我作好了 05/07 18:57
8F：→ H45:做完了？我看这程式有Race Condition，也解决了吗？ 05/07 22:51
9F：推 PsMonkey:违反版规 4.1，锁文软性惩罚 05/08 10:41
10F：→ PsMonkey:讲错了，是 4.2 XD 05/08 10:42
11F：→ doggingg:恩~在下方补上join就可以同步了，谢谢 05/08 14:20