Android 指定有线网或Wifi进行网络请求

Android 指定有线网或Wifi进行网络请求

一、前言：

有些场景需要指定特定的网络进行通讯；
比如Wifi 和有线网同开的设备，指定某个网络进行通讯；或者某些指定网络进行通讯的场景。

最近刚好开发了Wifi 和有线网同开同联的需求，顺便提分享特定网络请求的代码。

Android11上修改有线网和wifi共存：
https://blog.csdn.net/wenzhi20102321/article/details/133913924

二、指定网络通讯测试

1、 窗口命令 ping -I 网络节点 IP

测试通过节点对应的网络访问某个ip

130|console:/ # 
130|console:/ # ping wwwbaidu.com
PING wwwbaidu.com (45.194.224.35) 56(84) bytes of data.
64 bytes from 45.194.224.35: icmp_seq=1 ttl=43 time=13.6 ms
64 bytes from 45.194.224.35: icmp_seq=2 ttl=43 time=13.4 ms
64 bytes from 45.194.224.35: icmp_seq=3 ttl=43 time=38.7 ms
64 bytes from 45.194.224.35: icmp_seq=4 ttl=43 time=13.5 ms
^C
--- wwwbaidu.com ping statistics ---
4 packets transmitted, 4 received, 0% packet loss, time 3004ms
rtt min/avg/max/mdev = 13.452/19.851/38.744/10.908 ms
console:/ # 
console:/ # 
console:/ # ping -I eth0 www.baidu.com
PING www.a.shifen.com (157.148.69.80) from 192.168.31.174 eth0: 56(84) bytes of data.
64 bytes from 157.148.69.80: icmp_seq=1 ttl=46 time=15.0 ms
64 bytes from 157.148.69.80: icmp_seq=2 ttl=46 time=14.5 ms
64 bytes from 157.148.69.80: icmp_seq=3 ttl=46 time=15.2 ms
64 bytes from 157.148.69.80: icmp_seq=4 ttl=46 time=14.6 ms
^C
--- www.a.shifen.com ping statistics ---
4 packets transmitted, 4 received, 0% packet loss, time 3004ms
rtt min/avg/max/mdev = 14.580/14.877/15.257/0.294 ms
console:/ # 
console:/ # ping -I wlan0 www.baidu.com
PING www.a.shifen.com (157.148.69.80) from 192.5.1.34 wlan0: 56(84) bytes of data.
64 bytes from 157.148.69.80: icmp_seq=1 ttl=41 time=478 ms
64 bytes from 157.148.69.80: icmp_seq=2 ttl=41 time=99.9 ms
64 bytes from 157.148.69.80: icmp_seq=3 ttl=41 time=89.0 ms
64 bytes from 157.148.69.80: icmp_seq=4 ttl=41 time=96.1 ms
^C
--- www.a.shifen.com ping statistics ---
5 packets transmitted, 4 received, 20% packet loss, time 4005ms
rtt min/avg/max/mdev = 89.084/191.015/478.886/166.248 ms
console:/ # 

这里可以看到有线网和wifi都是对外正常进行通讯的。
未指定-I 的情况使用的是默认的网络。

2、Java 代码指定特定网络通讯

通过Java代码设置指定网络进行通讯

private void testNetwork() {
    Log.i(TAG, "testNetwork");
    ConnectivityManager connectivityManager = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
    NetworkRequest.Builder builder = new NetworkRequest.Builder();

    // 设置指定的网络传输类型
    // wifi: NetworkCapabilities.TRANSPORT_WIFI
    // 有线网络： NetworkCapabilities.TRANSPORT_ETHERNET
    //builder.addTransportType(NetworkCapabilities.TRANSPORT_ETHERNET);

    // 设置感兴趣的网络功能
    builder.addCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET);

    NetworkRequest request = builder.build();
    ConnectivityManager.NetworkCallback callback = new ConnectivityManager.NetworkCallback() {
        @Override
        public void onAvailable(Network network) {
            super.onAvailable(network);
            Log.i(TAG, "已根据功能和传输类型找到合适的有线网络");
            Log.i(TAG, "testnet onAvailable network = " + network.toString());

            // 通过network.openConnection 来获取URLConnection
            try {
                HttpURLConnection urlConnection = (HttpURLConnection) network.openConnection(new URL("https://www.baidu.com"));

                if (urlConnection != null) {
                    int responseCode = urlConnection.getResponseCode();
                    String responseMessage = urlConnection.getResponseMessage();
                    Log.i(TAG, "testEthernetonAvailable responseCode = " + responseCode);
                    Log.i(TAG, "testEthernet onAvailable responseMessage = " + responseMessage);
                    InputStream inputStream = urlConnection.getInputStream();
                    String result = new BufferedReader(new InputStreamReader(inputStream))
                            .lines().parallel().collect(Collectors.joining("\n"));
                    Log.i(TAG, "testEthernet onAvailable result = " + result);
                }
            } catch (IOException e) {
                Log.e(TAG, "testEthernet onAvailable error = " + e.getMessage());
            }
            connectivityManager.unregisterNetworkCallback(this);
        }

    };

    connectivityManager.registerNetworkCallback(request, callback);
    connectivityManager.requestNetwork(request, callback);
}

关键是NetworkRequest.Builder.addCapability 指定网络

三、指定特定网络的demo app 开发

1、效果图：

上图显示的有：

（1）wifi 和 有线网的 ip地址
（2）指定某个网络请求数据
（3）设置请求特定的网址
（4）返回请求的时间，网络的id，网址的html源码内容

这里的网络的id 是当前请求网络的 Network 对象的网络id值，同时 dumpsys connectivity 命令是可以看到的。

2、实际测试结果说明：

实际测试情况：

（1）当WiFi 和 有线网同时连接的情况
指定是没有作用的，请求网络使用的是高优先级的网络，这里是有线网网络。
通过 Network toString() 信息可以看到 当前连接网络的network id。

（2）只开单一网络的情况
指定网络是有作用的；
如果开启有线网，指定WiFi 网络是无法进行数据请求的
如果开启Wifi，指定有线网是无法进行数据请求的
默认网络是可以正常请求网络数据的。

3、获取不同网络ip地址的代码：

可以通过代码查看Wifi 和有线网的 Ip地址

    //getIpAddress,第二个参数是决定是获取的wifi的ip地址还是有线网的ip地址
    public static String getIpAddress(Context context, boolean isGetWifiIp) {
        Network network = null;
        if (isGetWifiIp) {
            network = getWlanNet(context);
        } else {
            network = getFirstEthernet(context);
        }
        if (network == null) {
            return "";
        }
        ConnectivityManager mConnectivityManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
        final LinkProperties linkProperties = mConnectivityManager.getLinkProperties(network);
        if (linkProperties != null) {
            for (LinkAddress linkAddress : linkProperties.getLinkAddresses()) {
                InetAddress inetAddress = linkAddress.getAddress();
                if (inetAddress instanceof Inet4Address) {
                    return inetAddress.getHostAddress();
                }
            }
        }
        return "";
    }

    //getFirstEthernet
    private static Network getFirstEthernet(Context context) {
        ConnectivityManager mConnectivityManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
        final Network[] networks = mConnectivityManager.getAllNetworks();
        for (final Network network : networks) {
            NetworkInfo networkInfo = mConnectivityManager.getNetworkInfo(network);
            if (networkInfo != null && networkInfo.getType() == ConnectivityManager.TYPE_ETHERNET) {
                return network;
            }
        }
        return null;
    }

    //getFirstWlan
    private static Network getWlanNet(Context context) {
        ConnectivityManager mConnectivityManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
        final Network[] networks = mConnectivityManager.getAllNetworks();
        for (final Network network : networks) {
            NetworkInfo networkInfo = mConnectivityManager.getNetworkInfo(network);
            if (networkInfo != null && networkInfo.getType() == ConnectivityManager.TYPE_WIFI) {
                return network;
            }
        }
        return null;
    }

通过上面的代码 getIpAddress 方法，是可以分别获取到Wifi 和有线网的 Ip的！

4、demo代码下载地址

https://download.csdn.net/download/wenzhi20102321/88450072