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Fetching form value in Java class

 
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Fetching form value in Java class
kensington
3 Apr, 2008 - 04:17 PM
Post #1

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In my Tomcat 4.1.27 container (with no struts), I am trying to pass a form value to a JavaBean but I keep getting NullPointerException on the web page when I call the JavaBean.

This does compile but I cant get the form value in my JSP. I assume I am doing something wrong with my request object. Please advise how I can make this work.
CODE

public class First
{
    private HttpServletRequest request;
    private String lastname;

    public First()
    {
         lastname= (String) request.getParameter("lastname");
    }
  
    /* Getter and Setter Methods */
     public String getLastname() {
    return lastname;
     }

      public void setLastname(String lastname) {
    this.lastname = lastname;
      }


    public FetchFormValue()
    {
        if(lastname.equals("Smith")
        {
             //do stuff for Smith
        }
        else
        {
            //do other stuff
        }
    }
..
}


Please advise.
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bhandari
RE: Fetching Form Value In Java Class
4 Apr, 2008 - 12:13 AM
Post #2

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QUOTE
if(lastname.equals("Smith")
{
//do stuff for Smith
}
else
{
//do other stuff
}


Check your objects against null value before invoking non-static methods on them.
For String equals method, there is another way around to avoid NPE as:
CODE

if("Smith".equals(lastname))
        {
             //do stuff for Smith
        }
        else
        {
            //do other stuff
        }
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1lacca
RE: Fetching Form Value In Java Class
4 Apr, 2008 - 01:27 AM
Post #3

code.rascal
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In the constructor the request object is not initialized.
You can get hold of the HttpRequest object at two places: in a servlet in doPost or doGet, or in the JSP either from as the predefined variable request from a scriptlet, or from the useBean directive.
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