Kotlin 实现的工具类，获取本机内网 IP 和公网 IP

IpUtil

import org.json.JSONException
import org.json.JSONObject
import java.io.BufferedInputStream
import java.io.ByteArrayOutputStream
import java.io.IOException
import java.lang.Exception
import java.net.*

/**
 * Created by xiaofei on 2019/1/15.
 */
object IpUtil {
    /**
     * 获取本机内网 IP 地址，Android 内同步调用
     */
    fun getLocalIP(): String? {
        var hostIp: String? = null
        try {
            val nis = NetworkInterface.getNetworkInterfaces()
            var ia: InetAddress?
            while (nis.hasMoreElements()) {
                val ni = nis.nextElement() as NetworkInterface
                val ias = ni.inetAddresses
                while (ias.hasMoreElements()) {
                    ia = ias.nextElement()
                    if (ia is Inet6Address) {
                        continue// skip ipv6
                    }
                    val ip = ia?.hostAddress
                    if ("127.0.0.1" != ip) {
                        hostIp = ia?.hostAddress
                        break
                    }
                }
            }
        } catch (e: SocketException) {
            e.printStackTrace()
        }
        return hostIp
    }

    /**
     * 获取本机公网 IP 地址，Android 内异步调用
     */
    fun getNetIp(): String? {
        var byteArrayOutputStream: ByteArrayOutputStream? = null
        var bufferedInputStream: BufferedInputStream? = null
        var result: String? = null
        var httpConnection: HttpURLConnection? = null
        try {
            val infoUrl = URL("http://pv.sohu.com/cityjson?ie=utf-8")
            httpConnection = infoUrl.openConnection() as HttpURLConnection
            //设置连接时间，10秒
            httpConnection.connectTimeout = 10 * 1000
            httpConnection.readTimeout = 10 * 1000

            //数据编码格式，这里utf-8
            httpConnection.setRequestProperty("Charset", "utf-8");
            //添加cookie,cookie规则需开发者自定
//            urlConnection.setRequestProperty("Cookie", Constants.COOCKIE_KEY + token);
            //设置返回结果的类型，这里是json
            httpConnection.setRequestProperty("accept", "application/json");
            //这里设置post传递的内容类型，这里json
            httpConnection.setRequestProperty("Content-Type", "application/json");
            //开启客户端与Url所指向的资源的网络连接
            httpConnection.connect();
            val responseCode = httpConnection.responseCode
            if (responseCode == HttpURLConnection.HTTP_OK) {
                bufferedInputStream = BufferedInputStream(httpConnection.inputStream)
                byteArrayOutputStream = ByteArrayOutputStream()
                //httpUrlConnection返回传输字节的长度，创建一个byte 数组。
                val b = ByteArray(httpConnection.contentLength)
                var length = 0

                while (bufferedInputStream.read(b).apply { length = this } > 0) {
                    byteArrayOutputStream.write(b, 0, length)
                }
                result = byteArrayOutputStream.toString("utf-8")
                // 从反馈的结果中提取出IP地址
                val start = result.indexOf("{")
                val end = result.indexOf("}")
                var json: String? = null
                if (start != -1 && end != -1){
                    json = result.substring(start, end + 1)
                }
                if (json != null) {
                    try {
                        val jsonObject = JSONObject(json)
                        result = jsonObject.optString("cip")
                    } catch (e: JSONException) {
                        e.printStackTrace()
                    }
                }else{
                    result = null
                }
                return result
            }
        } catch (e: MalformedURLException) {
            e.printStackTrace()
        } catch (e: IOException) {
            e.printStackTrace()
        } finally {
            try {
                byteArrayOutputStream?.close()
                bufferedInputStream?.close()
                //解除连接，释放网络资源
                httpConnection?.disconnect()
            } catch (e: Exception) {
                e.printStackTrace()
            }
        }
        return result
    }
}