我编写了一个应用程序,该应用程序应该对主机所在的子网中的所有客户端执行ping操作(使用isReachable),但是当它在XP计算机(SP2)上运行时,它无法获取所有主机,我得到了奇怪的结果。它似乎与线程链接在一起,就好像我加入了一个连接并有效地迫使应用程序使用它可以正常工作的一个线程一样。它在Windows 7和ubuntu linux中无需连接就可以正常工作,因此我对为什么它落在XP上有些困惑。它由两个类组成,现在请张贴它们。对Java来说还很新,所以希望它并不明显。提前致谢。

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;
}
}

最佳答案

努力解决ping问题,不仅不能在XP上正常运行,而且在发现的一些主机上isReachable()失败了。并不是理想的解决方案,因为它现在依赖于平台,但仍将运行WMI查询,因此无论如何都与Windows绑定(bind)在一起。

感谢您的光临。

关于java - 在XP上使用isReachable()进行线程子网ping,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/3617598/

10-12 02:58