util--每分钟自动检测是否断网，若断网，便重启网卡

package seablog.reconet;

import java.io.IOException;
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.text.SimpleDateFormat;
import java.util.Collections;
import java.util.Date;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;
import java.util.Timer;
import java.util.TimerTask;
/**
 * 每分钟自动检测是否断网，若断网，便重启网卡
 * <br>
 * Usage:  java -jar RecoNet.jar -dev dev_id [-host ping_host]
 * <br>
 * 附：<a href="http://www.233.com/microsoft/zonghe/20110103/144530473.html">devcon.exe程序下载</a>
 */
public class RecoNet extends TimerTask {
	RecoNetConfig cfg;

	public RecoNet(RecoNetConfig cfg) {
		this.cfg = cfg;
	}

	/**
	 * 网络是否正常
	 */
	public boolean isConnected(String host) {
		try {
			InetAddress.getByName(host);
			return true;
		} catch (UnknownHostException e) {
			return false;
		}
	}

	public void disableDev(String dev) throws IOException {
		Runtime.getRuntime().exec("devcon disable " + dev);

	}

	public void enableDev(String dev) throws IOException {
		Runtime.getRuntime().exec("devcon enable " + dev);
	}

	static SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm");
	Set<String> runningSet = Collections.synchronizedSet(new HashSet<String>());

	public void run() {
		try {
			// isRunning = true;
			String now = sdf.format(new Date());
			if (runningSet.contains(now)) {
				System.out.println(now + " Already Run.");
				return;
			}

			if (runningSet.size() > 24 * 60) {
				runningSet.clear();
			}
			runningSet.add(now);

			if (isConnected(cfg.getHost())) {
				System.out.println(now + " Ping OK.[" + cfg.getHost() + "]");

				return;
			}

			System.out.println(now + " Reboot " + cfg.getDevID() + ".");
			disableDev(cfg.getDevID());
			// 休眠5秒钟，等待disableDev执行...
			Thread.sleep(1000 * 5);
			enableDev(cfg.getDevID());
		} catch (Throwable e) {
			e.printStackTrace();
		}
	}

	static String ARG_HELP = "help";
	static String ARG_DEV = "-dev";
	static String ARG_HOST = "-host";
	
	/**
	 * 定时检测无线网络
	 */
	public static void main(String[] args) {
		if (args.length == 0 || ARG_HELP.equalsIgnoreCase(args[0])) {
			System.out
					.println("Usage:\tjava -jar RecoNet.jar -dev dev_id [-host ping_host]");
			System.out
					.println("e.g.\tjava -jar RecoNet.jar -dev *DEV_422C* -host baidu.com\n");

			return;
		}

		Map<String, String> map = new HashMap<String, String>();
		try {
			for (int i = 0; i < args.length; i += 2) {
				map.put(args[i].toLowerCase(), args[i + 1]);
			}
		} catch (IndexOutOfBoundsException e) {
			// do nothing
		}

		RecoNetConfig cfg = new RecoNetConfig();

		if (map.get(ARG_DEV) != null){
			cfg.setDevID(map.get(ARG_DEV));
		}
		if (map.get(ARG_HOST) != null){
			cfg.setHost(map.get(ARG_HOST));
		}
		map.clear();
		// 每分钟执行
		new Timer().scheduleAtFixedRate(new RecoNet(cfg), 1000, 1000 * 60);
	}
}

package seablog.reconet;

public class RecoNetConfig {
	/**
	 * 网卡标识
	 */
	String devID = "*DEV_422C*";

	/**
	 * 用于测试是否断网
	 */
	String host = "baidu.com";

	public String getDevID() {
		return devID;
	}
	public void setDevID(String devID) {
		this.devID = devID;
	}
	public String getHost() {
		return host;
	}
	public void setHost(String host) {
		this.host = host;
	}

}