android31 Traceroute功能代码实现

Traceroute功能是通过向目标地址发送一系列的ICMP数据包，每次增加TTL（Time to Live）值，直到目标地址返回ICMP Time Exceeded消息，从而确定网络连接的路径。在Android中，可以通过以下代码实现Traceroute功能：

public static void traceroute(final String ipAddress, final int maxHops, final int timeout) {
    new Thread(new Runnable() {
        @Override
        public void run() {
            try {
                InetAddress address = InetAddress.getByName(ipAddress);
                for (int i = 1; i <= maxHops; i++) {
                    long startTime = System.currentTimeMillis();
                    Socket socket = new Socket();
                    socket.setSoTimeout(timeout);
                    socket.connect(new InetSocketAddress(address, 33434), timeout);
                    long endTime = System.currentTimeMillis();
                    socket.close();
                    System.out.println("Hop " + i + ": " + address.getHostAddress() + " (" + getHostName(address) + ") - " + (endTime - startTime) + "ms");
                    if (address.equals(socket.getInetAddress())) {
                        break;
                    }
                    address = socket.getInetAddress();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }).start();
}

private static String getHostName(InetAddress address) {
    String hostName = address.getCanonicalHostName();
    if (hostName.equalsIgnoreCase(address.getHostAddress())) {
        return "";
    } else {
        return hostName;
    }
}

在该代码中，我们使用Socket连接到目标地址的33434端口，并设置超时时间，当连接成功时，输出Hop（跳数）信息，然后将目标地址改为连接成功后返回的地址。当目标地址与连接成功后返回的地址相同时，结束Traceroute。