simple java program thread scan LAN ip

import java**.InetAddress;   
import java**.UnknownHostException;   
import java.util.ArrayList;   
import java.util.Iterator;   
 *   Scan local area network using the java thread  ip  Simple solution    
 * @author Administrator  
public class LanIP {   
    public static void main(String[] args) {   
        System.out.println("  Start ......");   
        LanIP ip = new LanIP();   
        ArrayList<String> list =  ip.getLanIPArrayList();   
        System.out.println("  Finally, the number of  ===>"+list.size());   
    public ArrayList<String> getLanIPArrayList() {   
        ArrayList<String> arrayIP = null;   
        try {   
            InitSystem initSystem = null;   
            initSystem = new InitSystem();   
            Thread thread = new Thread(initSystem);   
            arrayIP = initSystem.getArrayIPUsed();   
        } catch (UnknownHostException e) {   
        } catch (InterruptedException e) {   
        return arrayIP;   
    private class InitSystem implements Runnable {   
        private int firstIP = 2;//   Check the IP address of the last one starting point     
        private int lastIP = 255;//   Check the IP address of the last end point     
        private volatile ArrayList<Thread> arrayThread;//   Child thread segment     
        private final int MAXTHREADNUM = 30; //   The maximum number of threads simultaneously sub-     
        private int threadNumNow;//   The number of ongoing sub-thread     
        private volatile ArrayList<String> arrayIP;//   LAN IP address of all possible query result sets     
        private volatile ArrayList<String> arrayIPUsed;//   LAN IP address already in use query result set     
        private InitSystem(String ip) {   
            arrayIP = new ArrayList<String>();   
            arrayIPUsed = new ArrayList<String>();   
            arrayThread = new ArrayList<Thread>();   
        private InitSystem() throws UnknownHostException {   
        private synchronized ArrayList<String> getArrayIPUsed() {   
            try {   
                System.out.println("getArrayIPUsed:  arrayIP.size===>"+arrayIP.size());   
                while (arrayIP.size() > 0) {   
            } catch (InterruptedException e) {   
            return arrayIPUsed;   
        private void setIPAddressList(String ip) {   
            //   According to this ip address lookup in the LAN it all possible   IP   Address set     
            int lastPointIndex = ip.lastIndexOf('.');   
            String stringIPHead = ip.substring(0, ++lastPointIndex);   
            String stringIP = null;   
            for (int i = firstIP; i <= lastIP; i++) {   
                stringIP = stringIPHead + i;   
            System.out.println("  Enter into here ... arrayIP the total number of  :"+arrayIP.size());   
        public void run() {   
            synchronized (this) {   
                try {   
                    System.out.println("run()  arrayIP.size()===>"+arrayIP.size());   
                    System.out.println("run()  threadNumNow===>"+threadNumNow);   
                    while (arrayIP.size() > 0) {   
                        while (threadNumNow >= MAXTHREADNUM) {   
                            System.out.println("  Threads beyond the 30, stay behind  ...");   
                            for (Thread thread : arrayThread) {   
                                if (!thread.getState().equals(   
                                        Thread.State.TERMINATED)) {   
                            arrayThread = new ArrayList<Thread>();   
                        Thread thread = new Thread(new InnerClass(arrayIP   
                } catch (Exception e) {   
        private class InnerClass implements Runnable {   
            //   Check whether a thread can be connected to IP     Is then added to the corresponding IP array     
            private String ip;   
            private InnerClass(String ip) {   
                System.out.println("InnerClass ip===>"+ip);   
                this.ip = ip;   
            private boolean isUsedIPAddress(String ip) {   
                synchronized (this) {   
                    System.out.println("  Enter here  .....");   
                    //  To determine the IP address if the current LAN connection is available   IP   
                    Process process = null;   
                    BufferedReader bufReader = null;   
                    String bufReadLineString = null;   
                    try {   
                        process = Runtime.getRuntime().exec(   
                                "ping " + ip + " -w 100 -n 1");   
                        bufReader = new BufferedReader(new InputStreamReader(   
                        for (int i = 0; i < 6 && bufReader != null; i++) {   
                        bufReadLineString = bufReader.readLine();   
                        if (bufReadLineString == null) {   
                            return false;   
                        if (bufReadLineString.indexOf("timed out") > 0  
                                || bufReadLineString.length() < 17  
                                || bufReadLineString.indexOf("invalid") > 0) {   
                            return false;   
                    } catch (IOException e) {   
                    return true;   
            public void run() {   
                synchronized (this) {   
                    if (isUsedIPAddress(ip)) {   

  Access to the LAN IP address using the name of the computer  .mac  Address. Working Group  

System.out.println("  MAC is the corresponding card  :");

NetworkInterface ne=NetworkInterface.getByInetAddress(InetAddress.getByName(""));


String mac_s=hexByte(mac[0])+":"+hexByte(mac[1])+":"+ hexByte(mac[2])+":"+hexByte(mac[3])+":"+ hexByte(mac[4])+":"+hexByte(mac[5]);System.out.println(mac_s);

  Result of the program  :  MAC is the corresponding card  : 00:0c:f1:20:75:58 
标签: lt, import java, java util, string args, ioexception, implements, main string, private class, arraylist, java program, iterator, bufferedreader, inputstreamreader, program thread, list ip
分类: Java
时间: 2010-12-20


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