Question

我已经为主机所在的子网上的所有客户端编写了一个应该ping（使用isReachable）的应用程序但是当它在XP机器（SP2）上运行时我得到了奇怪的结果它无法获得所有主机。它似乎与线程相关联，就像我放入一个连接并有效地强制应用程序使用它工作的一个线程。它在Windows 7和ubuntu linux中没有连接的情况下运行良好，所以我有点难过为什么它会在XP上崩溃。它现在由两个类别组成。对于java来说也是相当新的，所以希望它没有什么明显的。提前谢谢。

Main.java

package subnetping;
import java.io.IOException;
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.logging.Level;
import java.util.logging.Logger;

public class Main {
public static void main(String[] args) {
    //Set this to your ip and netmask
    Network myNetwork = new Network("192.168.1.33", 24);
   Thread t = null;
   for(String aHost : myNetwork.getClients()){
       t = new Thread(new pinger(aHost));
       t.start();

//           Following makes it work on XP by forcing wait on thread
//           try {
//               t.join();
//           } catch (InterruptedException ex) {
//               Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
//           }

   }
}
public static class pinger implements Runnable{
    private String host;
    private InetAddress address;
    public pinger(String host){
        this.host = host;
        try {
            address = InetAddress.getByName(host);
        } catch (UnknownHostException ex) {
            Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
        }
    }
    public void run(){
        try {
            if (address.isReachable(3000)) {
                System.out.println(host + " reachable");
            } 
        } catch (IOException ex) {
            Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
        }
    }
}
}

Network.java

package subnetping;

import java.util.ArrayList;
import java.util.List;

public class Network {
private String subnet = "";
private int subnetMask;
private List<String> myClients = new ArrayList<String>();

public Network(String hostIP, int subnetMask){
    this.subnetMask = subnetMask;
    this.subnet = getSubNet(hostIP, this.subnetMask);
    createClients();
}

private String ipToBinary(String ipNumber){
    String[] temp;
    String binOctet1;
    String binOctet2;
    String binOctet3;
    String binOctet4;
    String ipAsBinary;

    temp = ipNumber.split("\\.");
    binOctet1 = padLeftToEight(Integer.toBinaryString(Integer.parseInt(temp[0])));
    binOctet2 = padLeftToEight(Integer.toBinaryString(Integer.parseInt(temp[1])));
    binOctet3 = padLeftToEight(Integer.toBinaryString(Integer.parseInt(temp[2])));
    binOctet4 = padLeftToEight(Integer.toBinaryString(Integer.parseInt(temp[3])));
    ipAsBinary = binOctet1 + binOctet2 + binOctet3 + binOctet4;
    return ipAsBinary;
}

private String binaryToIP(String binaryIP){
    return longToIP(Long.parseLong(binaryIP, 2));
}

private Long ipToLong (String ipNumber){
    String[] temp;

    String binOctet1;
    String binOctet2;
    String binOctet3;
    String binOctet4;
    Long ipAsLong;

    temp = ipNumber.split("\\.");
    binOctet1 = padLeftToEight(Integer.toBinaryString(Integer.parseInt(temp[0])));
    binOctet2 = padLeftToEight(Integer.toBinaryString(Integer.parseInt(temp[1])));
    binOctet3 = padLeftToEight(Integer.toBinaryString(Integer.parseInt(temp[2])));
    binOctet4 = padLeftToEight(Integer.toBinaryString(Integer.parseInt(temp[3])));
    ipAsLong = Long.parseLong((binOctet1 + binOctet2 + binOctet3 + binOctet4),2);

    return ipAsLong;
}

private String longToIP (Long LongIP){
    String binOctet1;
    String binOctet2;
    String binOctet3;
    String binOctet4;
    int intOctet1;
    int intOctet2;
    int intOctet3;
    int intOctet4;
    String fullBin;
    String ipAsString;

    fullBin = padLeftToThirtyTwo(Long.toBinaryString(LongIP));

    binOctet1 = fullBin.substring(0, 8);
    binOctet2 = fullBin.substring(8, 16);
    binOctet3 = fullBin.substring(16, 24);
    binOctet4 = fullBin.substring(24);

    intOctet1 = Integer.parseInt(binOctet1, 2);
    intOctet2 = Integer.parseInt(binOctet2, 2);
    intOctet3 = Integer.parseInt(binOctet3, 2);
    intOctet4 = Integer.parseInt(binOctet4, 2);

    ipAsString = intOctet1 + "." + intOctet2 + "." + intOctet3 + "." + intOctet4;

    return ipAsString;
}

private String padLeftToEight(String octet){
    String paddedOctet = octet;
    if(octet.length() == 8){
        return octet;
    }else{
        for( int i = 1; i <= (8 - octet.length()); i++){
           paddedOctet = "0" + paddedOctet;
        }

        return paddedOctet;
    }
}

private String padLeftToThirtyTwo(String ipNumber){
    String paddedIPNumber = ipNumber;
    if(ipNumber.length() == 32){
        return ipNumber;
    }else{
        for( int i = 1; i <= (32 - ipNumber.length()); i++){
           paddedIPNumber = "0" + paddedIPNumber;
        }

        return paddedIPNumber;
    }
}

private String padRightToThirtyTwo(String ipNumber){
    String paddedIPNumber = ipNumber;
    if(ipNumber.length() == 32){
        return ipNumber;
    }else{
        for( int i = 1; i <= (32 - ipNumber.length()); i++){
           paddedIPNumber = paddedIPNumber + "0";
        }

        return paddedIPNumber;
    }
}

private String getSubNet(String ipNumber, int subnetMask){
    for(int i = 0; i < subnetMask; i++){
        subnet = subnet + ipToBinary(ipNumber).charAt(i);
    }
    return binaryToIP(padRightToThirtyTwo(subnet));
}

private void createClients(){
    long subnetLong;
    long clientRange;

    clientRange = ((long) Math.pow(2L, (32L - subnetMask)) - 2);
    subnetLong = ipToLong(this.subnet);

    for(int i = 1; i <= clientRange; i ++){
        myClients.add(longToIP(subnetLong + i));
    }

}

public List<String> getClients(){
    return myClients;
}
}

Answer 1

已经炮击ping以解决问题它不仅在XP上无法正常工作，isReachable（）在ping发现的几台主机上失败了。不是一个理想的解决方案，因为它现在依赖于平台，但无论如何都会运行与Windows相关的WMI查询。

感谢您的光临。

在XP上使用isReachable（）进行子线程ping

1 个答案: