服务器的真实IP怎么利用java进行获取

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.io.UnsupportedEncodingException;
import java.net.HttpURLConnection;
import java.net.Inet4Address;
import java.net.InetAddress;
import java.net.InterfaceAddress;
import java.net.NetworkInterface;
import java.net.SocketException;
import java.net.URL;
import java.net.URLConnection;
import java.net.URLEncoder;
import java.net.UnknownHostException;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
 
import javax.servlet.http.HttpServletRequest;
 
import org.apache.http.HttpEntity;
import org.apache.http.NameValuePair;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.util.EntityUtils;
import org.springframework.http.HttpMethod;
 
/**
 * 常用工具类
 *
 * @author 席红蕾
 * @date 2016-09-27
 * @version 1.0
 */
public class WebToolUtils {
 
  /**
   * 获取本地IP地址
   *
   * @throws SocketException
   */
  public static String getLocalIP() throws UnknownHostException, SocketException {
    if (isWindowsOS()) {
      return InetAddress.getLocalHost().getHostAddress();
    } else {
      return getLinuxLocalIp();
    }
  }
 
  /**
   * 判断操作系统是否是Windows
   *
   * @return
   */
  public static boolean isWindowsOS() {
    boolean isWindowsOS = false;
    String osName = System.getProperty("os.name");
    if (osName.toLowerCase().indexOf("windows") > -1) {
      isWindowsOS = true;
    }
    return isWindowsOS;
  }
 
  /**
   * 获取本地Host名称
   */
  public static String getLocalHostName() throws UnknownHostException {
    return InetAddress.getLocalHost().getHostName();
  }
 
  /**
   * 获取Linux下的IP地址
   *
   * @return IP地址
   * @throws SocketException
   */
  private static String getLinuxLocalIp() throws SocketException {
    String ip = "";
    try {
      for (Enumeration en = NetworkInterface.getNetworkInterfaces(); en.hasMoreElements();) {
        NetworkInterface intf = en.nextElement();
        String name = intf.getName();
        if (!name.contains("docker") && !name.contains("lo")) {
          for (Enumeration enumIpAddr = intf.getInetAddresses(); enumIpAddr.hasMoreElements();) {
            InetAddress inetAddress = enumIpAddr.nextElement();
            if (!inetAddress.isLoopbackAddress()) {
              String ipaddress = inetAddress.getHostAddress().toString();
              if (!ipaddress.contains("::") && !ipaddress.contains("0:0:") && !ipaddress.contains("fe80")) {
                ip = ipaddress;
                System.out.println(ipaddress);
              }
            }
          }
        }
      }
    } catch (SocketException ex) {
      System.out.println("获取ip地址异常");
      ip = "127.0.0.1";
      ex.printStackTrace();
    }
    System.out.println("IP:"+ip);
    return ip;
  }
 
  /**
   * 获取用户真实IP地址，不使用request.getRemoteAddr();的原因是有可能用户使用了代理软件方式避免真实IP地址,
   *
   * 可是，如果通过了多级反向代理的话，X-Forwarded-For的值并不止一个，而是一串IP值，究竟哪个才是真正的用户端的真实IP呢？
   * 答案是取X-Forwarded-For中第一个非unknown的有效IP字符串。
   *
   * 如：X-Forwarded-For：192.168.1.110, 192.168.1.120, 192.168.1.130,
   * 192.168.1.100
   *
   * 用户真实IP为： 192.168.1.110
   *
   * @param request
   * @return
   */
  public static String getIpAddress(HttpServletRequest request) {
    String ip = request.getHeader("x-forwarded-for");
    if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
      ip = request.getHeader("Proxy-Client-IP");
    }
    if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
      ip = request.getHeader("WL-Proxy-Client-IP");
    }
    if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
      ip = request.getHeader("HTTP_CLIENT_IP");
    }
    if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
      ip = request.getHeader("HTTP_X_FORWARDED_FOR");
    }
    if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
      ip = request.getRemoteAddr();
    }
    return ip;
  }
 
  /**
   * 向指定URL发送GET方法的请求
   *
   * @param url
   *      发送请求的URL
   * @param param
   *      请求参数，请求参数应该是 name1=value1&name2=value2 的形式。
   * @return URL 所代表远程资源的响应结果
   */
  // public static String sendGet(String url, String param) {
  // String result = "";
  // BufferedReader in = null;
  // try {
  // String urlNameString = url + "?" + param;
  // URL realUrl = new URL(urlNameString);
  // // 打开和URL之间的连接
  // URLConnection connection = realUrl.openConnection();
  // // 设置通用的请求属性
  // connection.setRequestProperty("accept", "*/*");
  // connection.setRequestProperty("connection", "Keep-Alive");
  // connection.setRequestProperty("user-agent", "Mozilla/4.0 (compatible;
  // MSIE 6.0; Windows NT 5.1;SV1)");
  // // 建立实际的连接
  // connection.connect();
  // // 获取所有响应头字段
  // Map> map = connection.getHeaderFields();
  // // 遍历所有的响应头字段
  // for (String key : map.keySet()) {
  // System.out.println(key + "--->" + map.get(key));
  // }
  // // 定义 BufferedReader输入流来读取URL的响应
  // in = new BufferedReader(new
  // InputStreamReader(connection.getInputStream()));
  // String line;
  // while ((line = in.readLine()) != null) {
  // result += line;
  // }
  // } catch (Exception e) {
  // System.out.println("发送GET请求出现异常！" + e);
  // e.printStackTrace();
  // }
  // // 使用finally块来关闭输入流
  // finally {
  // try {
  // if (in != null) {
  // in.close();
  // }
  // } catch (Exception e2) {
  // e2.printStackTrace();
  // }
  // }
  // return result;
  // }
 
  /**
   * 向指定 URL 发送POST方法的请求
   *
   * @param url
   *      发送请求的 URL
   * @param param
   *      请求参数，请求参数应该是 name1=value1&name2=value2 的形式。
   * @return 所代表远程资源的响应结果
   */
  public static void sendPost(String pathUrl, String name, String pwd, String phone, String content) {
    // PrintWriter out = null;
    // BufferedReader in = null;
    // String result = "";
    // try {
    // URL realUrl = new URL(url);
    // // 打开和URL之间的连接
    // URLConnection conn = realUrl.openConnection();
    // // 设置通用的请求属性
    // conn.setRequestProperty("accept", "*/*");
    // conn.setRequestProperty("connection", "Keep-Alive");
    // conn.setRequestProperty("user-agent",
    // "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
    // // 发送POST请求必须设置如下两行
    // conn.setDoOutput(true);
    // conn.setDoInput(true);
    // // 获取URLConnection对象对应的输出流
    // out = new PrintWriter(conn.getOutputStream());
    // // 发送请求参数
    // out.print(param);
    // // flush输出流的缓冲
    // out.flush();
    // // 定义BufferedReader输入流来读取URL的响应
    // in = new BufferedReader(
    // new InputStreamReader(conn.getInputStream()));
    // String line;
    // while ((line = in.readLine()) != null) {
    // result += line;
    // }
    // } catch (Exception e) {
    // System.out.println("发送 POST 请求出现异常！"+e);
    // e.printStackTrace();
    // }
    // //使用finally块来关闭输出流、输入流
    // finally{
    // try{
    // if(out!=null){
    // out.close();
    // }
    // if(in!=null){
    // in.close();
    // }
    // }
    // catch(IOException ex){
    // ex.printStackTrace();
    // }
    // }
    // return result;
    try {
      // 建立连接
      URL url = new URL(pathUrl);
      HttpURLConnection httpConn = (HttpURLConnection) url.openConnection();
 
      // //设置连接属性
      httpConn.setDoOutput(true);// 使用 URL 连接进行输出
      httpConn.setDoInput(true);// 使用 URL 连接进行输入
      httpConn.setUseCaches(false);// 忽略缓存
      httpConn.setRequestMethod("POST");// 设置URL请求方法
      String requestString = "客服端要以以流方式发送到服务端的数据...";
 
      // 设置请求属性
      // 获得数据字节数据，请求数据流的编码，必须和下面服务器端处理请求流的编码一致
      byte[] requestStringBytes = requestString.getBytes("utf-8");
      httpConn.setRequestProperty("Content-length", "" + requestStringBytes.length);
      httpConn.setRequestProperty("Content-Type", "  application/x-www-form-urlencoded");
      httpConn.setRequestProperty("Connection", "Keep-Alive");// 维持长连接
      httpConn.setRequestProperty("Accept", "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8");
      httpConn.setRequestProperty("Accept-Encoding", "gzip, deflate");
      httpConn.setRequestProperty("Accept-Language", "zh-CN,zh;q=0.8,en-US;q=0.5,en;q=0.3");
      httpConn.setRequestProperty("User-Agent", "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:49.0) Gecko/20100101 Firefox/49.0");
      httpConn.setRequestProperty("Upgrade-Insecure-Requests", "1");
 
      httpConn.setRequestProperty("account", name);
      httpConn.setRequestProperty("passwd", pwd);
      httpConn.setRequestProperty("phone", phone);
      httpConn.setRequestProperty("content", content);
 
      // 建立输出流，并写入数据
      OutputStream outputStream = httpConn.getOutputStream();
      outputStream.write(requestStringBytes);
      outputStream.close();
      // 获得响应状态
      int responseCode = httpConn.getResponseCode();
 
      if (HttpURLConnection.HTTP_OK == responseCode) {// 连接成功
        // 当正确响应时处理数据
        StringBuffer sb = new StringBuffer();
        String readLine;
        BufferedReader responseReader;
        // 处理响应流，必须与服务器响应流输出的编码一致
        responseReader = new BufferedReader(new InputStreamReader(httpConn.getInputStream(), "utf-8"));
        while ((readLine = responseReader.readLine()) != null) {
          sb.append(readLine).append("\n");
        }
        responseReader.close();
      }
    } catch (Exception ex) {
      ex.printStackTrace();
    }
  }
 
  /**
   * 执行一个HTTP POST请求，返回请求响应的HTML
   *
   * @param url
   *      请求的URL地址
   * @param params
   *      请求的查询参数,可以为null
   * @return 返回请求响应的HTML
   */
  public static void doPost(String url, String name, String pwd, String phone, String content) {
    // 创建默认的httpClient实例.
    CloseableHttpClient httpclient = HttpClients.createDefault();
    // 创建httppost
    HttpPost httppost = new HttpPost(url);
    // 创建参数队列
    List formparams = new ArrayList();
    formparams.add(new BasicNameValuePair("account", name));
    formparams.add(new BasicNameValuePair("passwd", pwd));
    formparams.add(new BasicNameValuePair("phone", phone));
    formparams.add(new BasicNameValuePair("content", content));
 
    UrlEncodedFormEntity uefEntity;
    try {
      uefEntity = new UrlEncodedFormEntity(formparams, "UTF-8");
      httppost.setEntity(uefEntity);
      System.out.println("executing request " + httppost.getURI());
      CloseableHttpResponse response = httpclient.execute(httppost);
      try {
        HttpEntity entity = response.getEntity();
        if (entity != null) {
          System.out.println("--------------------------------------");
          System.out.println("Response content: " + EntityUtils.toString(entity, "UTF-8"));
          System.out.println("--------------------------------------");
        }
      } finally {
        response.close();
      }
    } catch (Exception e) {
      e.printStackTrace();
    } finally {
      // 关闭连接,释放资源
      try {
        httpclient.close();
      } catch (IOException e) {
        e.printStackTrace();
      }
    }
 
  }
}