JSP页里如何获得自己本机的外网IP? 注意不是局域网IP,也不是127.0.0.1

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import java.net.*;
public class GetIp { public static int isInnerIP(long a_ip)//检查ip地址是否是内网ip
{
 int bValid = -1;
 if ((a_ip >> 24 == 0xa) || (a_ip >> 16 == 0xc0a8) || (a_ip >> 22 == 0x2b0))
 {
 bValid = 0;
 }
 return bValid;
}

// 将127.0.0.1 形式的IP地址转换成10进制整数，这里没有进行任何错误处理
public static long ipToLong(String strIP)
{
 long[] ip = new long[4];
 //先找到IP地址字符串中.的位置
 int position1 = strIP.indexOf(".");
 int position2 = strIP.indexOf(".", position1 + 1);
 int position3 = strIP.indexOf(".", position2 + 1);
 //将每个.之间的字符串转换成整型
 ip[0] = Long.parseLong(strIP.substring(0, position1));
 ip[1] = Long.parseLong(strIP.substring(position1 + 1, position2));
 ip[2] = Long.parseLong(strIP.substring(position2 + 1, position3));
 ip[3] = Long.parseLong(strIP.substring(position3 + 1));
 return (ip[0] << 24) + (ip[1] << 16) + (ip[2] << 8) + ip[3];
}

public static void main(String[] args) {
 String ip;
 try
 {
 InetAddress in = InetAddress.getLocalHost();
 InetAddress[] all = InetAddress.getAllByName(in.getHostName());
 //通过本机主机名，遍历多个ip
 for (int i = 0; i < all.length; i++)
 {
 String tmp=null;
 tmp=ip=all[i].getHostAddress().toString();
 System.out.println("IP = " +tmp);//输出计算机所有的ip地址
 if (isInnerIP(ipToLong(tmp)) == -1)//检查是不是外网ip，如果是就保存文件
 {
 /*WriteFile(ip);//将ip地址写入文件
 System.out.println("IP保存在同目录IP.txt文件中"); System.out.println("同目录IP.txt文件中的IP是：" + ReadFile());*/
 System.out.println(ip);

 }
 }
 }
 catch (UnknownHostException e)
 {
 System.out.println(e.getMessage());
 }
}
}
public static String findMyIp()throws Exception{
java.net.URL url = new java.net.URL("http://www.ip138.com/ip2city.asp");
java.net.URLConnection urlConnection = url.openConnection();
urlConnection.setAllowUserInteraction(false);
java.io.BufferedReader in = new java.io.BufferedReader(new java.io.InputStreamReader(url.openStream()));
String inputLine;
String ip=null;
while ((inputLine = in.readLine()) != null){
    int start=0;
int end=0;
    if((start=inputLine.indexOf("您的IP地址是"))!=-1){
     start=inputLine.indexOf("[");
     end=inputLine.indexOf("]");
     ip=inputLine.substring(start+1,end);
break;
}
}
in.close();
return ip;
}  从网上看到的一种思路，是读取http://www.ip138.com/网页的内容，从里面提取IP地址，但是，读取出来以后才发现，ip地址的内容是放在一个iframe中的，是由http://www.ip138.com/ip2city.asp文件生成的。
不知道楼主可否告知还有什么好办法？
public class ipServlet extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {

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.getRemoteAddr();
}
String url = request.getHeader("Referer");
String Trageturl = request.getRequestURL().toString();
response.setContentType("text/html");
response.setCharacterEncoding("UTF-8");
PrintWriter out = response.getWriter();
out.println("<html>");
out.println("<body>");
out.println("<head>");
out.println("<title>获得真实IP测试</title>");
out.println("</head>");
out.println("<body>IP测试例子 ");
out.println("IP: "+ip);
out.println("Url测试例子 ");
out.println("url: "+url);
out.println("网址测试例子 ");
out.println("Trageturl: "+Trageturl);
out.println("</body>");
out.println("</html>");

}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {

this.doGet(request, response);
}
}
1个月前自己写的IP测试的servlet例子。供参考。servlet配置

<servlet>
<servlet-name>ip</servlet-name>
<servlet-class>iptest.ipServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>ip</servlet-name>
<url-pattern>/iptest</url-pattern>
</servlet-mapping>本人一直想把这个放到网站上测试，看是否能得到外网IP。如果有哪个兄弟有自己的个人网站。请帮忙测试下。并告知我。不胜感激。
上次不会引用JAVA代码，这次重新引用下。
public class ipServlet extends HttpServlet {public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {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.getRemoteAddr();
}
String url = request.getHeader("Referer");
String Trageturl = request.getRequestURL().toString();
response.setContentType("text/html");
response.setCharacterEncoding("UTF-8");
PrintWriter out = response.getWriter();
out.println(" <html>");
out.println(" <body>");
out.println(" <head>");
out.println(" <title>获得真实IP测试 </title>");
out.println(" </head>");
out.println(" <body> IP测试例子 ");
out.println("IP: "+ip);
out.println(" Url测试例子 ");
out.println("url: "+url);
out.println(" 网址测试例子 ");
out.println("Trageturl: "+Trageturl);
out.println(" </body>");
out.println(" </html>");}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {this.doGet(request, response);
}
}
<servlet>
<servlet-name>ip </servlet-name>
<servlet-class>iptest.ipServlet </servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>ip </servlet-name>
<url-pattern>/iptest </url-pattern>
</servlet-mapping>