如何 ping IP地址

Question

public static void main(String[] args) throws UnknownHostException, IOException {
    String ipAddress = "127.0.0.1";
    InetAddress inet = InetAddress.getByName(ipAddress);

    System.out.println("Sending Ping Request to " + ipAddress);
    System.out.println(inet.isReachable(5000) ? "Host is reachable" : "Host is NOT reachable");

    ipAddress = "173.194.32.38";
    inet = InetAddress.getByName(ipAddress);

    System.out.println("Sending Ping Request to " + ipAddress);
    System.out.println(inet.isReachable(5000) ? "Host is reachable" : "Host is NOT reachable");
}

Answer 1

inetaddress.isreachable()根据Javadoc：

“..如果可以获得特权，典型的实现将使用ICMP回送请求，否则将尝试在目标主机的端口7（回送）上建立TCP连接..”。

选项#1(ICMP)通常需要管理（root）权限。