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JSP Cookies Example
This tutorial shows how to handle cookies in JSP pages.
In this tutorial you will learn how to add cookies through jsp page and then
show the value of the same cookie in another JSP page.
Let's understand the cookies. Cookies are short pieces
of data sent by web servers to the client browser. The cookies are saved to
clients hard disk in the form of small text file. Cookies helps the web servers
to identify web users, by this way server tracks the user. Cookies pay very
important role in the session tracking.
Cookie Class
In JSP cookie are the object of the class javax.servlet.http.Cookie.
This class is used to creates a cookie, a small amount of information sent by a
servlet to a Web browser, saved by the browser, and later sent back to the
server. A cookie's value can uniquely identify a client, so cookies are commonly
used for session management. A cookie has a name, a single value, and optional
attributes such as a comment, path and domain qualifiers, a maximum age, and a
version number.
The getCookies() method of the request object returns
an array of Cookie objects. Cookies can be constructed using the following code:
Cookie(java.lang.String name, java.lang.String value)
Cookie objects have the following methods.
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Method
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Description
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getComment()
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Returns the comment describing the purpose of
this cookie, or null if no such comment has been defined.
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getMaxAge()
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Returns the maximum specified age of the cookie.
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getName()
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Returns the name of the cookie.
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getPath()
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Returns the prefix of all URLs for which this
cookie is targeted.
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getValue()
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Returns the value of the cookie.
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setComment(String)
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If a web browser presents this cookie to a user,
the cookie's purpose will be described using this comment.
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setMaxAge(int)
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Sets the maximum age of the cookie. The cookie
will expire after that many seconds have passed. Negative values
indicate the default behavior: the cookie is not stored persistently,
and will be deleted when the user web browser exits. A zero value causes
the cookie to be deleted
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setPath(String)
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This cookie should be presented only with
requests beginning with this URL.
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setValue(String)
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Sets the value of the cookie. Values with
various special characters (white space, brackets and parentheses, the
equals sign, comma, double quote, slashes, question marks, the
"at" sign, colon, and semicolon) should be avoided. Empty
values may not behave the same way on all browsers.
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Example Using Cookies
No we will write code in JSP file to set and then
display the cookie.
Create Form
Here is the code of the form (cookieform.jsp) which
prompts the user to enter his/her name.
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<%@ page language="java" %>
<html>
<head>
<title>Cookie Input Form</title>
</head>
<body>
<form method="post" action="setcookie.jsp">
<p><b>Enter Your Name: </b><input type="text" name="username"><br>
<input type="submit" value="Submit">
</form>
</body>
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Above form prompts the user to enter the user name.
User input are posted to the setcookie.jsp file, which sets the cookie. Here is
the code of setcookie.jsp file:
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<%@ page language="java" import="java.util.*"%>
<%
String username=request.getParameter("username");
if(username==null) username="";
Date now = new Date();
String timestamp = now.toString();
Cookie cookie = new Cookie ("username",username);
cookie.setMaxAge(365 * 24 * 60 * 60);
response.addCookie(cookie);
%>
<html>
<head>
<title>Cookie Saved</title>
</head>
<body>
<p><a href="showcookievalue.jsp">Next Page to view the cookie value</a><p>
</body>
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Above code sets the cookie and then displays a link to
view cookie page. Here is the code of display cookie page (showcookievalue.jsp):
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<%@ page language="java" %>
<%
String cookieName = "username";
Cookie cookies [] = request.getCookies ();
Cookie myCookie = null;
if (cookies != null)
{
for (int i = 0; i < cookies.length; i++)
{
if (cookies [i].getName().equals (cookieName))
{
myCookie = cookies[i];
break;
}
}
}
%>
<html>
<head>
<title>Show Saved Cookie</title>
</head>
<body>
<%
if (myCookie == null) {
%>
No Cookie found with the name <%=cookieName%>
<%
} else {
%>
<p>Welcome: <%=myCookie.getValue()%>.
<%
}
%>
</body>
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When user navigates to the above the page, cookie value
is displayed.
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Current Comments
15 comments so far (post your own) View All Comments Latest 10 Comments:This is very good site.This site very useful to me.
Giving very good example with synataxes
Posted by srinu on Friday, 08.8.08 @ 12:49pm | #71765
This is very simple and good understandable example.
Posted by Manohar on Thursday, 06.12.08 @ 11:17am | #63092
it is really an interesting and easy way of learning JSP..but one thing i would like to say here.how we can view the more the one values stored inside the cookie.while displaying the third page....please upload more and more samples on Advance JSP..Thanks Alot..........
Posted by ISMAIL on Wednesday, 04.30.08 @ 15:45pm | #58215
There is one flaw.Dont enter any value in the first page.Press submit than press on the link.
It is showing "welcome:."
It should show error message.
Posted by Krunal on Sunday, 03.30.08 @ 00:14am | #54684
Cookie Class In JSP cookie are the object of the class javax.servlet.http.Cookie. This class is used to creates a cookie, a small amount of information sent by a servlet to a Web browser, saved by the browser, and later sent back to the server. A cookie's value can uniquely identify a client, so cookies are commonly used for session management. A cookie has a name, a single value, and optional attributes such as a comment, path and domain qualifiers, a maximum age, and a version number. The getCookies() method of the request object returns an array of Cookie objects. Cookies can be constructed using the following code: Cookie(java.lang.String name, java.lang.String value) Cookie objects have the following methods. Method Description getComment() Returns the comment describing the purpose of this cookie, or null if no such comment has been defined. getMaxAge() Returns the maximum specified age of the cookie. getName() Returns the name of the cookie. getPath() Returns the prefix of all URLs for which this cookie is targeted. getValue() Returns the value of the cookie. setComment(String) If a web browser presents this cookie to a user, the cookie's purpose will be described using this comment. setMaxAge(int) Sets the maximum age of the cookie. The cookie will expire after that many seconds have passed. Negative values indicate the default behavior: the cookie is not stored persistently, and will be deleted when the user web browser exits. A zero value causes the cookie to be deleted setPath(String) This cookie should be presented only with requests beginning with this URL. setValue(String) Sets the value of the cookie. Values with various special characters (white space, brackets and parentheses, the equals sign, comma, double quote, slashes, question marks, the "at" sign, colon, and semicolon) should be avoided. Empty values may not behave the same way on all browsers. Example Using Cookies No we will write code in JSP file to set and then display the cookie. Create Form Here is the code of the form (cookieform.jsp) which prompts the user to enter his/her name. <%@ page language="java" %> <html> <head> <title>Cookie Input Form</title> </head> <body> <form method="post" action="setcookie.jsp"> <p><b>Enter Your Name: </b><input type="text" name="username"><br> <input type="submit" value="Submit"> </form> </body> Above form prompts the user to enter the user name. User input are posted to the setcookie.jsp file, which sets the cookie. Here is the code of setcookie.jsp file:
<%@ page language="java" import="java.util.*"%> <% String username=request.getParameter("username"); if(username==null) username=""; Date now = new Date(); String timestamp = now.toString(); Cookie cookie = new Cookie ("username",username); cookie.setMaxAge(365 * 24 * 60 * 60); response.addCookie(cookie); %>
Posted by Parameter on Wednesday, 03.12.08 @ 22:53pm | #52502
it was really nice . thank u ! but one thing
i would like to say here first of all enter user name after that it will show the next link page and then again clicking that link it will show the saved cookie . but whenever again whenever i entered a new cookie it won't displaying the old cookie , it simply showing the new cookie . i got confused so please help me.
Posted by dasari on Friday, 02.15.08 @ 12:42pm | #48371
Thanks for tutorial. It is easy for understanding.
Posted by Phong Tran on Wednesday, 02.13.08 @ 11:54am | #48125
this is very nice and useful thanq
Posted by deepthi on Wednesday, 12.19.07 @ 14:51pm | #42948
Its nice and easy. Thanks for giving this tutorial.
Posted by suresh on Tuesday, 12.18.07 @ 18:39pm | #42840
this examples help me lot for doing projects and learn, like this I want example on jsp how to give link pdf files, in project when we click on the help button to display the pdf files
Posted by majjikishore on Tuesday, 11.13.07 @ 15:59pm | #37224