requestcontextholder获取ip

可以使用RequestContextHolder获取当前请求的HttpServletRequest对象，然后从HttpServletRequest对象中获取客户端的IP地址。示例如下：

import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;

import javax.servlet.http.HttpServletRequest;

public class MyController {

    public String myMethod() {
        HttpServletRequest request = ((ServletRequestAttributes) RequestContextHolder.getRequestAttributes()).getRequest();
        String ipAddress = request.getHeader("X-Forwarded-For");
        if (ipAddress == null || ipAddress.length() == 0 || "unknown".equalsIgnoreCase(ipAddress)) {
            ipAddress = request.getHeader("Proxy-Client-IP");
        }
        if (ipAddress == null || ipAddress.length() == 0 || "unknown".equalsIgnoreCase(ipAddress)) {
            ipAddress = request.getHeader("WL-Proxy-Client-IP");
        }
        if (ipAddress == null || ipAddress.length() == 0 || "unknown".equalsIgnoreCase(ipAddress)) {
            ipAddress = request.getHeader("HTTP_CLIENT_IP");
        }
        if (ipAddress == null || ipAddress.length() == 0 || "unknown".equalsIgnoreCase(ipAddress)) {
            ipAddress = request.getHeader("HTTP_X_FORWARDED_FOR");
        }
        if (ipAddress == null || ipAddress.length() == 0 || "unknown".equalsIgnoreCase(ipAddress)) {
            ipAddress = request.getRemoteAddr();
        }
        return ipAddress;
    }
}

以上代码会依次从请求头中获取客户端IP地址，如果无法获取则返回RemoteAddr。注意，由于可能存在代理服务器，因此需要从请求头中获取真实IP地址，而不是直接从RemoteAddr中获取。