java获取ip的方式，注意多级代理的方式获取

public String getIP() {
String clientIP = ServletActionContext.getRequest().getHeader("x-forwarded-for");
if (Validator.isNull(clientIP) || "unknown".equalsIgnoreCase(clientIP)) {
clientIP = ServletActionContext.getRequest().getHeader("Proxy-Client-IP");
}
if (Validator.isNull(clientIP) || "unknown".equalsIgnoreCase(clientIP)) {
clientIP = ServletActionContext.getRequest().getHeader("WL-Proxy-Client-IP");
}
if (Validator.isNull(clientIP) || "unknown".equalsIgnoreCase(clientIP)) {
clientIP = ServletActionContext.getRequest().getRemoteAddr();
}
if (Validator.isNotNull(clientIP)) {//防止通过了多级反向代理
String str[] = FormatString.split(clientIP, ",");
for (int i = 0; i < str.length; i++) {
if (!"unknown".equalsIgnoreCase(clientIP)) {
clientIP = str[i];
break;
}
}
}
return clientIP;
}