多线程获取局域网内的ip

package com.aiks.ip;

import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

/**

• 实测可用
• 获取当前局域网的所有ip和主机名
• @author 18061
  
  /
  public class MyNetIp {
  public static void main(String[] args) {

  NewGetIp1 task1 = new NewGetIp1();
  Thread thread1 = new Thread(task1, "线程1");
  thread1.start();
  
  NewGetIp2 task2 = new NewGetIp2();
  Thread thread2 = new Thread(task2, "线程2");
  thread2.start();
  
  NewGetIp3 task3 = new NewGetIp3();
  Thread thread3 = new Thread(task3, "线程3");
  thread3.start();
  
  NewGetIp4 task4 = new NewGetIp4();
  Thread thread4 = new Thread(task4, "线程4");
  thread4.start();
  

  }
  }

class NewGetIp1 implements Runnable {
private int num = 255;
Lock l = new ReentrantLock();
boolean flag=true;
@Override
public void run() {
// TODO Auto-generated method stub
try {
while (true) {
l.lock();
if (num > 180) {
String name = “192.168.37.”;
name = name + Integer.toString(num);
num–;
// System.out.println(name);
InetAddress ia = InetAddress.getByName(name);
String ip = ia.getHostAddress();
String hostName = ia.getHostName();
if (!ip.toString().equals(hostName.toString())) {
System.out.println(Thread.currentThread().getName()

                            + "===" + ip + "=====" + hostName);
                    System.out.println("-------------------------");
                } else {
                    //System.out.println("*****");
                }                
            }else  if(flag){
                //这里定义标记,如果该线程完成任务.标记设置为false
                System.out.println(Thread.currentThread().getName()+"的总数:"+count);
                flag=false;
            }
            l.unlock();
        }

    } catch (UnknownHostException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
}

}

class NewGetIp2 implements Runnable {
private int num = 180;
Lock l = new ReentrantLock();
boolean flag=true;
@Override
public void run() {
// TODO Auto-generated method stub
try {
while (true) {
l.lock();
if (num > 120) {

                String name = "192.168.37.";
                name = name + Integer.toString(num);
                num--;
                // System.out.println(name);
                InetAddress ia = InetAddress.getByName(name);
                String ip = ia.getHostAddress();
                String hostName = ia.getHostName();
                if (!ip.toString().equals(hostName.toString())) {
                    System.out.println(Thread.currentThread().getName()
                            + "===" + ip + "=====" + hostName);
                    System.out.println("-------------------------");
                } else {
                    //System.out.println("*****");
                }                
            }else  if(flag){
                System.out.println(Thread.currentThread().getName()+"的总数:"+count);
                flag=false;
            }
            l.unlock();
        }

    } catch (UnknownHostException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
}

}

class NewGetIp3 implements Runnable {
private int num = 120;
Lock l = new ReentrantLock();
boolean flag= true;

@Override
public void run() {
    // TODO Auto-generated method stub
    try {

        while (true) {
            l.lock();
            if (num > 60) {

                String name = "192.168.37.";
                name = name + Integer.toString(num);
                num--;

                // System.out.println(name);
                InetAddress ia = InetAddress.getByName(name);
                String ip = ia.getHostAddress();
                String hostName = ia.getHostName();
                if (!ip.toString().equals(hostName.toString())) {

                    System.out.println(Thread.currentThread().getName()
                            + "===" + ip + "=====" + hostName);
                    System.out.println("-------------------------");
                } else {
                    //System.out.println("*****");
                }

            }else if(flag){
                System.out.println(Thread.currentThread().getName()+"的总数:"+count);
                flag=false;
            }
            l.unlock();
        }

    } catch (UnknownHostException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
}

}

class NewGetIp4 implements Runnable {
private int num = 60;
Lock l = new ReentrantLock();
boolean flag=true;
@Override
public void run() {
// TODO Auto-generated method stub
try {

        while (true) {
            l.lock();
            if (num > 0) {

                String name = "192.168.37.";
                name = name + Integer.toString(num);
                num--;

                // System.out.println(name);
                InetAddress ia = InetAddress.getByName(name);
                String ip = ia.getHostAddress();
                String hostName = ia.getHostName();
                if (!ip.toString().equals(hostName.toString())) {

                    System.out.println(Thread.currentThread().getName()
                            + "===" + ip + "=====" + hostName);
                    System.out.println("-------------------------");
                } else {
                    //System.out.println("*****");
                }

            }else  if(flag){
                System.out.println(Thread.currentThread().getName()+"的总数:"+count);
                flag=false;
            }
            l.unlock();
        }

    } catch (UnknownHostException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
}

}