Hello group,
I realized that my code in red (see below-earlier post) was being executed
for each row as the table is built.
That is why my request did not contain a value. I modified the code as
follows:
<c:forEach var="person" begin="0" items="${requestScope.personList}">
<tr>
<form id="personForm" action="DeletePerson" method="post">
<td>${person.id} </td>
<td>${person.firstName} </td>
<td>${person.lastName} </td>
<th>
<input type="submit" value="DeletePerson"
onclick="<c:set var="delete_person" scope="session"
value="${person}"/>">
</th>
</form>
</tr>
</c:forEach>
Now I get a person (in the session scope) but it is always the last row in
the table (which makes sense since it is being evaluated once for each row).
I can't figure out how to pass the person object of the row that contains
the delete button I am clicking.
I am able to successfully remove the person and persist the changes but it's
the wrong person!
Can anyone help me solve this? I have searched everywhere for an answer to
no avail.
Thanks,
Cj .
_____
From: java-ee-j2ee-programming-with-passion@googlegroups.com
[mailto:java-ee-j2ee-programming-with-pass...@googlegroups.com] On Behalf Of
Constantine J Coutsoukes
Sent: Monday, January 26, 2009 11:16 PM
To: 'Java EE (J2EE) Programming with Passion!'
Subject: [java ee programming] Re: Java Persistence API (JPA) Basics
homework
Hi.
I'm trying to create a delete button for each row then set a request
parameter with the current "person".
The bold lines are the lines of code I added to the example:
<c:forEach var="person" begin="0" items="${requestScope.personList}">
<tr>
<form id="personForm" action="DeletePerson" method="post">
<td>${person.id} </td>
<td>${person.firstName} </td>
<td>${person.lastName} </td>
<th><input type="submit" value="DeletePerson"
name="DeletePerson">
<c:set var="delete_person" scope="request"
value="${person}"/>
</input>
</th>
</form>
</tr>
</c:forEach>
This reaches my DeletePersonServlet, which is almost identical to the
CreatePersonServlet, except that I try to extract the person from the
request like this:
Person person = (Person) request.getAttribute("delete_person");
And then further down instead of persisting the object I try to remove it:
em.remove(person);
This is where I get:
javax.servlet.ServletException: java.lang.IllegalArgumentException: Object:
null is not a known entity type.
In other words my parameter is not being set by my above code in red.
I am baffled by this homework. Any help would be greatly appreciated.
Thanks,
Cj .
-----Original Message-----
From: java-ee-j2ee-programming-with-passion@googlegroups.com
[mailto:java-ee-j2ee-programming-with-pass...@googlegroups.com] On Behalf Of
zoso967
Sent: Monday, January 26, 2009 7:49 PM
To: Java EE (J2EE) Programming with Passion!
Cc: zoso...@nyc.rr.com
Subject: [java ee programming] Java Persistence API (JPA) Basics homework
Hello group.
I am having trouble with the Java Persistence API (JPA) Basics
homework.
The homework says:
For each entry (user) being displayed, provide a "Delete" option
The only example of this was in the CDLibrary project but that was a
full blown JSF application and the majority of the work was done by
the IDE.
The source for our homework project is not a JSF application and the
example uses JSF to do the deletes.
Are we supposed to make our homework a JSF application or are we just
supposed to use JSTL?
In either case, I am having trouble. I seem to have trouble with most
of the UI homeworks.
Can anyone point me in the right direction?
Thanks,
Cj .
--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups "Java
EE (J2EE) Programming with Passion!" group.
To post to this group, send email to
java-ee-j2ee-programming-with-passion@googlegroups.com
To unsubscribe from this group, send email to
java-ee-j2ee-programming-with-passion+unsubscr...@googlegroups.com
For more options, visit this group at
http://groups.google.com/group/java-ee-j2ee-programming-with-passion?hl=en
-~----------~----~----~----~------~----~------~--~---
