java通过ping 判断网络是否正常

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader; /**
* 判断网络连接状况.
*
*/
public class NetState { public boolean isConnect(){
boolean connect = false;
Runtime runtime = Runtime.getRuntime();
Process process;
try {
process = runtime.exec("ping " + "www.baidu.com");
InputStream is = process.getInputStream();
InputStreamReader isr = new InputStreamReader(is);
BufferedReader br = new BufferedReader(isr);
String line = null;
StringBuffer sb = new StringBuffer();
while ((line = br.readLine()) != null) {
sb.append(line);
}
System.out.println("返回值为:"+sb);
is.close();
isr.close();
br.close(); if (null != sb && !sb.toString().equals("")) {
String logString = "";
if (sb.toString().indexOf("TTL") > 0) {
// 网络畅通
connect = true;
} else {
// 网络不畅通
connect = false;
}
}
} catch (IOException e) {
e.printStackTrace();
}
return connect;
} public static void main(String[] args) {
NetState netState = new NetState();
System.out.println(netState.isConnect()); }
}