클라이언트 IP 추출 메서드 추가

pom.xml

@@ -118,6 +118,14 @@
 		    <artifactId>icu4j</artifactId>
 		    <version>75.1</version>
 		</dependency>
+
+		<dependency>
+		    <groupId>javax.servlet</groupId>
+		    <artifactId>javax.servlet-api</artifactId>
+		    <version>4.0.1</version>
+		    <scope>provided</scope>
+		</dependency>
+
 	</dependencies>
 
 

src/main/java/cokr/xit/applib/AppCmmnUtil.java

@@ -3,8 +3,40 @@ package cokr.xit.applib;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
+import javax.servlet.http.HttpServletRequest;
+
 public class AppCmmnUtil {
 
+	/**
+     * http 서블릿 요청으로부터 클라이언트 IP를 반환한다.
+     * @param http 서블릿 요청
+     * @return 클라이언트 IP
+     */
+	public static String getClientIpAddr(HttpServletRequest request) {
+		String REGEXP_IPV4_ADDR = "^(([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])\\.){3}([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])$";
+		String[] headerNames = {"X-Forwarded-For","Proxy-Client-IP","WL-Proxy-Client-IP","HTTP_CLIENT_IP","HTTP_X_FORWARDED_FOR"};
+
+		String ip = "";
+		for(String headerName : headerNames) {
+			ip = request.getHeader(headerName);
+		    if(ip != null && ip.contains(",")) {
+	    		ip = ip.split(",",-1)[0];
+	    	}
+		    if(ip != null && Pattern.matches(REGEXP_IPV4_ADDR, ip)) {
+		        break;
+		    }
+		}
+
+	    if(ip != null && ip.contains(",")) {
+    		ip = ip.split(",",-1)[0];
+    	}
+	    if(ip == null || !Pattern.matches(REGEXP_IPV4_ADDR, ip)) {
+	        ip = request.getRemoteAddr();
+	    }
+
+	    return ip;
+	}
+
 	/**
      * 전화번호(유선,무선) 형식인지 체크한다.
      * @param 문자열