JSP tags as object constructors?

Question

Hi,
I want to instantiate an object in a tag handler and then use the object in my JSP code. For example:
<objConstructor varName="myObj" field1="foo" field2="bar" />
<%
out.println(myObj.getField1() + " " + myObj.getField2());
%>
Is there an elegant way to do this in JSP, or is there a more appropriate way? I want to allow non-programmers to edit the stuff.
Thanks,
Greg

Answer 1

Sure, you just need to add a TEI class for your tag. So if your tag class is named ObjConstructor.java, you'd need a class called ObjConstructorTEI.java that looks something like this:
import javax.servlet.jsp.tagext.*;
public class ObjConstructorTEI extends TagExtraInfo
   public VariableInfo[] getVariableInfo(TagData data)
      VariableInfo info1 = new VariableInfo(data.getAttributeString("id"),"class.name.for.the.object", true, VariableInfo.AT_BEGIN);
      VariableInfo[] info = { info1 } ;
      return info;
}Note: I changed your varName to id in this example, just to follow the convention used by other tags like jsp:useBean.
I copied it from a tag I wrote a while back, so I don't remember the specifics of the VariableInfo API, but since you're using it the same way as I did, it should work.