java多线程

main() 你是想调用 public static void main(String[] args) 吧

对,代码简写的,编译没问题想的是开两条线程监控输入流,貌似system.in读取后就停了,就这样想的.

你启动了两个线程，有可能在你输入了start之后，进入到 while(true)循环体里面的时候另外一个线程抢占了资源。所以就一直处于等待状态。楼主可以把出现的问题描述的更加详细一点。这样别人才能更加清楚的回答，ps:其实我也是一个菜鸟了。

Thread start = new Thread(new Test ());if(br.readLine().equals("start")){

Thread start = new Thread(new Test());
Thread stop = new Thread(new Test());你这个线程是两个空线程啊，你得把自己的线程类弄进去啊。

不行啊,完全不理解多线程,完整代码如下,麻烦看下public class Test implements Runnable{
@Override
public void run() {
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
String s = null;
try {
s = br.readLine();
if(s.equals("start")){
while(true){
System.out.println("Hello");
Thread.sleep(2000);
}
}else if(s.equals("stop")){
System.exit(0);
}
} catch (Exception e) {
e.printStackTrace();
}
}

public static void main(String[] args) {
Thread thread = new Thread(Test());
thread.start();
}
}

谢了,解决了.另外问下,API文档完全看不懂,这正常吗?编程究竟该怎么学,就这点错误弄的我还以为代码逻辑有问题.

然后控制台输入 start
public class T1 implements Runnable {
public static void main(String[] args) {
Thread start = new Thread(new T1());
start.start();
} @Override
public void run() {
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
try {
if (br.readLine().equals("start")) {
while (true) {
System.out.print("Hello");
Thread.sleep(1000);
}
} else {
System.exit(0);
}
} catch (IOException e) {
e.printStackTrace();
} catch (InterruptedException e) {
e.printStackTrace();
} }
}

public class T1 implements Runnable
{
public static void main(String[] args)
{
Thread start = new Thread(new T1());
start.start();
} @Override
public void run()
{
while (true)
{
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
try
{
if (br.readLine().equals("start"))
{ System.out.print("Hello");
Thread.sleep(1000);
} else
{
System.exit(0);
}
} catch (IOException e)
{
e.printStackTrace();
} catch (InterruptedException e)
{
e.printStackTrace();
}
} }
}

弄了一天还是搞不定,哪位帮我直接写了吧.需求:
输入start,开始打印,若再次输入start,提示程序已启动
输入stop,暂停打印
输入exit,退出程序
,确实写晕了

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;public class Demo implements Runnable {
private int count = 0;
private boolean flag = false;
public void run() {
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
String msg = null;
try {
while ((msg = br.readLine()) != null) {
if ("start".equals(msg) && count == 0) {
System.out.println("请继续输入:");
count++;
flag = false;
} else if (count != 0 && "start".equals(msg)) {
System.out.println("程序已经运行!");
}
if ("stop".equals(msg) && flag == false) {
System.out.println("输入停止!");
flag = true;
count = 0;
} else if ("exit".equals(msg)) {
System.exit(0);
}
if (!"start".equals(msg) && !"stop".equals(msg)
&& !"exit".equals(msg) && flag == false)
System.out.println(msg);
else if(flag == true && !"start".equals(msg)){
System.out.println("程序已经停止,不能打印了,请重新启动程序!");
}
}

} catch (IOException e) {
} finally {
if (br != null) {
try {
br.close();
} catch (IOException e) {
}
}
}
count = 0;
} public static void main(String[] args) {
Demo d = new Demo();
Thread start = new Thread(d);
// Thread stop = new Thread(d);
start.start();
// stop.start();
}
}
写了一个,用单线程的,你这个功能用不着多线程,而且多线程启动了,你不知道究竟输入的是哪个?每次输入的入口不一定相同,
你的程序最大的问题是将if语句放在了外面,而一旦进入while循环就是死循环,上面否决了多线程的想法,那么在单线程里面你的while循环根本出不去,还怎么输入数据呢?
不知道是否符合楼主的要求

while(true){sysout}里面是一个监听事件,换成直接打印一句sysout没用啊

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