IT 공부/JSP
Cookies
toraa
2022. 8. 1. 17:00
쿠키
; 웹 브라우저에 저장되는 작은 크기의 텍스트 데이터이다.
1. 생성 : Cookie 클래스 - request.getCookie( ) >> Cookie[ ] cookie
2. 메소드
. getName() : 쿠키 이름
. getValue(): 쿠키값 읽기
. setValue(String value)
. setMaxAge(int time) : 유효시간을 초단위로 설정
음수로 처리시, 브라우저가 닫히면 쿠키삭제 (기본값-1)
3. 클라이언트 전송
. response.addCookie();
4. 삭제되었거나 유효시간이 종료되지 않았다면, 같은 브라우저 서로 다른 페이지에서도 공유할 수 있다.
5. JSESSIONID
- 톰캣 컨테이너에서 세션을 유지하기 위해 발급되는 키
- 세션의 저장소를 생성할 때 사용하는 키
- 이후 해당 저장소에 접근할때도 사용된다.
1. 쿠키 객체 생성
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>쿠키</title>
</head>
<body>
<%
//쿠키객체생성 cookies --- > [new Cookie()][new Cookie()]...
Cookie cookie_name = new Cookie("name","deok");
Cookie cookie_age = new Cookie("age","23");
response.addCookie(cookie_name);
response.addCookie(cookie_age);
%>
<a href="jsp2.jsp">쿠키확인하기</a>
</body>
</html>2. 쿠키
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>cookies</title>
</head>
<body>
<%
Cookie[] cookies = request.getCookies();
if(cookies != null && cookies.length >0){
for(int i=0; i<cookies.length; i++){
out.print(cookies[i].getName());
out.print(":");
out.print(cookies[i].getValue());
out.print("<br>");
}
}
%>
</body>
</html>3. 쿠키 변경 확인
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>쿠키 변경 확인하기</title>
</head>
<body>
<%
Cookie cookie = new Cookie("name","web");
response.addCookie(cookie);
%>
<a href="jsp2.jsp">쿠키 변경 확인하기</a>
</body>
</html>4. 쿠키 삭제
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>쿠키삭제하기</title>
</head>
<body>
<%
Cookie[] cookies = request.getCookies();
if(cookies != null && cookies.length >0){
for(int i=0; i<cookies.length; i++){
if(cookies[i].getName().equals("name")){
Cookie cookie = new Cookie("name","");
cookie.setMaxAge(0);
response.addCookie(cookie);
out.print("쿠키가 삭제되었습니다.");
}
}
}
%>
<br>
<a href=jsp2.jsp>쿠키확인하기</a>
</body>
</html>5. 쿠키 확인
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>쿠키확인하기</title>
</head>
<body>
<%
Cookie cookie = new Cookie("name","jsp");
cookie.setMaxAge(60*60*24);
response.addCookie(cookie);
%>
<a href="jsp2.jsp">쿠키확인하기</a>
</body>
</html>
쿠키를 활용한 로그인/로그아웃
1. 로그인창
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>로그인 창</title>
</head>
<body>
<form action="jsp7.jsp" method="post">
아 이 디 : <input type="text" name="id"><br>
비밀번호 : <input type="password" name="pw"><br><br>
<input type="submit" value="확인">
</form>
</body>
</html>2. 로그인 실패
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>로그인 실패</title>
</head>
<body>
<%
String id = request.getParameter("id");
String pw = request.getParameter("pw");
if(id.equals("admin") && pw.equals("1234")){
Cookie cookie = new Cookie("ID","ADMIN");
response.addCookie(cookie);
out.print("<h2>환영합니당</h2>");
}
else{
out.print("<h3>로그인에 실패하였습니당 ㅠㅅㅠ</h3>");
}
%>
<a href="jsp8.jsp">메인창으로 이동합니당</a>
</body>
</html>3. 로그아웃 상태입니다
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>로그아웃 상태입니당</title>
</head>
<body>
<%
Cookie[] cookies = request.getCookies();
boolean isLogin = false;
if(cookies != null && cookies.length>0){
for(int i=0; i<cookies.length; i++){
String cookies_name = cookies[i].getName();
String cookies_value = cookies[i].getValue();
if(cookies_name.equals("ID") && cookies_value.equals("AdMIN")){
isLogin = true;
break;
}
}
}
if(isLogin){
out.print("<h2>로그인 상태입니당</h2>");
}
else{
out.print("<h2>로그아웃 상태입니당</h2>");
}
%>
<a href="jsp9.jsp">로그아웃</a>
</body>
</html>4. 로그아웃 되었습니당
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>로그아웃 되었습니당</title>
</head>
<body>
<%
Cookie cookie = new Cookie("ID","ADMIN");
cookie.setMaxAge(0); //로그아웃
response.addCookie(cookie);
%>
<h3>로그아웃 되었습니당ㅇㅅㅇ 다시 방문해주세요!</h3>
</body>
</html>