Difference between getAttribute(string) and getParameter(String)

[praveen kumar gowda]

hi guys,
i come to know how get Parameter method works.....In that,

1)when we submit the form without fields value(empty form) ,will the value is null or empty?

please explain me about get Attribute method..i am not clearing of this..

[Sabarish Venkat]

1. When you use getParameter() method and send it as empty you will get Null pointer exception since null values are retrived.

And the difference between getParameter() and getAttribute() is ,In getParameter you can retrive the values of the form.

Say you have

    User Name:<input type="text" name="user1"> 
 

In the above code you can see the name="user1" this the key for us to take the user name type by the user. In next page you can get it as

   String user= request.getParameter("user1");

Now you will get the user name typed by user.


For getAttribute(),

If you have a string value in a page and you want to take it to next page that time we use getAttribute(). It will get the value from previous page as session

Say ,

    String user="Java Ranch"; 
    session.setAttribute("name",user);  // here the name is the reference to get in next page and user is the value that holds the string "Java Ranch"

Now in next page you will get the session as,

    String Name = session.getAttribute("name").toString(); // here the reference name will retrieve the string value "Java Ranch" as a session

This is the difference ... Check the bold words for exact difference to say in one word