The Cookie class in Java represents HTTP cookies and allows servlets to create, read, and modify cookies. Cookies can store small amounts of user data on the client side and are commonly used for session tracking or storing user preferences. The Cookie class implements methods for getting and setting the name, value, domain, path, expiration, and other properties of a cookie. Servlets can use cookies to pass user-specific data between an HTML form and a servlet.
3. Purpose
• The Cookie provides an easy way for servlets to
read, create and manipulate HTTP-style cookies,
which allow servlets to store small amounts of data
on the client.
• Cookies are generally used for session tracking
or storing small amounts of user-specific
configuration information.
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4. Class summary
public class Cookie implements java.lang.Cloneable {
//constructor
public Cookie(String name,String value)l
//instance methods
public Object Clone();
public String getComment();
public String getDomain();
public String getMaxAge();
public String getName();
public String getPath();
public String getSecure();
public String getValue();
public String getVersion();
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5. Class summary
public void setComment(String purpose);
public void setDomain(String pattern);
public void setMaxAge(int Expiry);
public void setPath(String uri);
public void setSecure(boolean flag);
public void setDomain(String pattern);
public void setValue(String newValue);
public void setVersion(int v);
}
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6. Class summary
• Cookie()
Constructs a new cookie with a initial name and value
• clone()
To return a copy of object(duplicate cookie)
• getComment()
Returns comments associated with cookie
• getDomain()
Returns domain limitation associated with cookie
• getMaxAge()
Returns max age allowed for this cookie
• getPath
Returns path limitation for this servlet
• getSecure()
Returns true if the cookie requires a secure connection, false
otherwise
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7. • getName()
Returns name of the cookie
• getValue()
Returns value of the cookie in String format
• getVersion()
Returns version of the cookie
• setComment()
Sets the comment field of the cookie
• setDomain()
Specifies domain restriction pattern
• setMaxAge()
Specifies the maximum age of the cookie
• setPath()
Specifies path for cookie
• setSecure()
The secure flag indicates whether the cookie should be sent only over a secure
channel, such as SSL
• setValue()
Assigns new value to a cookie
• setVersion()
Servlets can send and receive cookies formatted to match either Netscape persistent
cookies or the newer
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8. Sample servlet to implement cookie
• cookiesform.html
<html>
<head><title>Cookies</title></head>
<body>
<form action="http://localhost:8080/lalitha/cookie">
Enter name
<input type="text" name="t1"/><br>
Enter qualification
<input type="text" name="t2"/><br>
<input type="submit" name="submit" value="Submit"/>
</form>
</body>
</html>
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9. • cookie.java
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class cookie extends HttpServlet {
public void doGet(HttpServletRequest req,
HttpServletResponse res)
throws IOException, ServletException
{
res.setContentType("text/html");
PrintWriter out = res.getWriter();
String name=req.getParameter("t1");
String qual=req.getParameter("t2");
Cookie c=new Cookie(name,qual);
res.addCookie(c);
out.println("cookies are added");
}
}
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