[网络协议]Java 测试可用IP(示例)

依据之前的博客 在知道如何利用Java得出本机IP地址及使用ping判断一个地址是否能够到达

以下是结合两者对判断本网段有多少可用的ip地址
1到255

代码示例：

import java.net.InetAddress;
import java.net.UnknownHostException;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.concurrent.LinkedBlockingDeque;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;

public class TestSocket {
    public static void main(String[] args) throws IOException {
      InetAddress in=InetAddress.getLocalHost();
      String str=in.getHostAddress();
      System.out.println("本机的IP地址"+str);
        String str2=str.substring(0,str.lastIndexOf(".")+1);
        ThreadPoolExecutor tpe=new ThreadPoolExecutor(100,200,5,TimeUnit.SECONDS,new LinkedBlockingDeque<>());

        for (int i=1;i<=255;i++){
            final int j=i;
            tpe.execute(new Runnable() {
                @Override
                public void run() {
                    Process p;
                    try{
                        p=Runtime.getRuntime().exec("ping "+str2+j);
                        BufferedReader br=new BufferedReader(new InputStreamReader(p.getInputStream(),"GBK"));

                        String temp=null;
                        boolean tag=false;
                        while((temp=br.readLine())!=null)
                        {
                            if(temp.contains("TTL"))
                            {
                                tag=true;
                                break;
                            }
                        }
                        if(tag)
                        {
                            System.out.println("it's can be uesd:"+str2+j);
                        }
                    }catch(IOException e)
                    {
                        System.out.println("gan!");
                        e.printStackTrace();
                    }
                }
            });
        }
    }
}

利用Java自带的线程池 缓存流里实例化输入流对象一行行读取数据