获取访问用户的客户端IP（适用于公网与局域网）.

/**
* 获取访问用户的客户端IP（适用于公网与局域网）.
*/
public final String getIpAddr(final HttpServletRequest request)
throws Exception {
if (request == null) {
throw (new Exception("getIpAddr method HttpServletRequest Object is null"));
}
String ipString = request.getHeader("x-forwarded-for");
if (StringUtils.isBlank(ipString) || "unknown".equalsIgnoreCase(ipString)) {
ipString = request.getHeader("Proxy-Client-IP");
}
if (StringUtils.isBlank(ipString) || "unknown".equalsIgnoreCase(ipString)) {
ipString = request.getHeader("WL-Proxy-Client-IP");
}
if (StringUtils.isBlank(ipString) || "unknown".equalsIgnoreCase(ipString)) {
ipString = request.getRemoteAddr();
}

// 多个路由时，取第一个非unknown的ip
final String[] arr = ipString.split(",");
for (final String str : arr) {
if (!"unknown".equalsIgnoreCase(str)) {
ipString = str;
break;
}
}

return ipString;
}