获取request请求的ip地址（java）

女爷i 2022-04-02 17:36 1259阅读 0赞

**获取request请求，最重要要了解`X-Forwarded-For和X-Real-IP。`**

**`       X-Forwarded-For`是用于记录代理信息的，每经过一级代理(匿名代理除外)，代理服务器都会把这次请求的`来源IP`追加在`X-Forwarded-For`中，格式如--> `X-Forwarded-For:123.123.123.123,456.456.456.456,789.789.789.789,这代表请求由123.123.123.123发出然后经过多层代理。`**

**`       X-Real-IP`，没有相关标准，上面的例子，如果配置了`X-Read-IP`，可能会有两种情况：**

// 最后一跳是正向代理，可能会保留真实客户端IP
    X-Real-IP: 123.123.123.123
    // 最后一跳是反向代理，比如Nginx，一般会是与之直接连接的客户端IP
    X-Real-IP: 789.789.789.789

**所以 ，如果只有一层代理，这两个头的值就是一样的；**

**下面直接上java代码：**

public class IpAddressUtil {
           /**
           * @Author : lilong
           * @Description :获取请求Ip地址
           * @Date : 10:22 2018/12/27
           **/
            public static String getIpAdrress(HttpServletRequest request) {
                //X-Real-IP，一般只记录真实发出请求的客户端IP
                String XRealIp = request.getHeader("X-Real-IP");
                //x_forwarded_for:  【用户经过代理时，代理会增加这个字段，nginx可用内置变量$http_x_forwarded_for取到这个字段，没有使用代理时，此字段为空】
                String XForwardedFor = request.getHeader("X-Forwarded-For");
                if(StringUtils.isNotEmpty(XForwardedFor) && !"unKnown".equalsIgnoreCase(XForwardedFor)){
                    //多次反向代理后会出现多个ip值，但只有第一个ip才是真实ip。所以只拿第一个就好
                    int index = XForwardedFor.indexOf(",");
                    if(index != -1){
                        return XForwardedFor.substring(0,index);
                    }else{
                        return XForwardedFor;
                    }
                }
                XForwardedFor = XRealIp;
                if(StringUtils.isNotEmpty(XForwardedFor) && !"unKnown".equalsIgnoreCase(XForwardedFor)){
                    return XForwardedFor;
                }
                if (StringUtils.isBlank(XForwardedFor) || "unknown".equalsIgnoreCase(XForwardedFor)) {
                    XForwardedFor = request.getHeader("Proxy-Client-IP");
                }
                if (StringUtils.isBlank(XForwardedFor) || "unknown".equalsIgnoreCase(XForwardedFor)) {
                    XForwardedFor = request.getHeader("WL-Proxy-Client-IP");
                }
                if (StringUtils.isBlank(XForwardedFor) || "unknown".equalsIgnoreCase(XForwardedFor)) {
                    XForwardedFor = request.getHeader("HTTP_CLIENT_IP");
                }
                if (StringUtils.isBlank(XForwardedFor) || "unknown".equalsIgnoreCase(XForwardedFor)) {
                    XForwardedFor = request.getHeader("HTTP_X_FORWARDED_FOR");
                }
                if (StringUtils.isBlank(XForwardedFor) || "unknown".equalsIgnoreCase(XForwardedFor)) {
                    XForwardedFor = request.getRemoteAddr();
                }
                return XForwardedFor;
            }
    }