@In (create=true)

[blackers]

I am recieving an error when I load my "gameHome" component. The error is as follows:

org.jboss.seam.RequiredException: In attribute requires non-null value: gameHome.oppTeamHome

My seam component is delcared as follows:

@Name("gameHome")
public class GameHome extends EntityHome<Game> {

 @In(create = true) TeamHome oppTeamHome;
 ...

Is my understanding that if I use create=true that the instance will be created if it's value is null. Am I missing something?

[christian.bauer]

Yes, it should be. Show TeamHome.java.

[blackers]

Here is the important part from TeamHome.java (as generated by seam-gen)

@Name("teamHome")
public class TeamHome extends EntityHome<Team> {

private static final long serialVersionUID = -6503138100502127742L;
@In(create = true)
ClubHome clubHome;
@In(create = true)
GradeHome gradeHome;
...

should the @Name here match the @In attributes name from GameHome.java?

[blackers]

The reason I have changed

 @In (create=true) TeamHome teamHome;

to

 @In (create=true) TeamHome oppTeamHome;

is because I also have a second TeamHome attribute in GameHome.java

@In(create = true) TeamHome oppTeamHome;
@In(create = true)
RoundHome roundHome;
@In(create = true)
GroundHome groundHome;
@In(create = true) TeamHome homeTeamHome;

Do i need to rename TeamHome.java to OppTeamHome.java and make another similar class called HomeTeamHome.java.

My database table Game has multiple foreign keys to the same table Team.

[tazman]

Use

@In(create=true, value="contextVariableName")

tazman

[blackers]

I have tried this with the same results.

[christian.bauer]

What do you want? Two local fields referencing the _same instance_ of the TeamHome component or two instances?

[blackers]

They should both be referencing 2 separate instances.

[christian.bauer]

Interesting, I don't think this is actually possible.

[blackers]

I should have said They should both be referencing a separate instance each.
not 2 instances each if that is not clear.

I have a set up simplified to the following.

Table Game
========
game_id
home_team_id --> fkey to table team field team_id
opp_team_id --> fkey to table team field team_id


Table Team
========
team_id
team_name




eg.


Table Game
========
game_id | home_team_id | opp_team_id
-------------------------------------------------
1 | 1 | 2
2 | 3 | 2


Table Team
========
team_id | team_name
--------------------------
1 | Team A
2 | Team B
3 | Team C


So what I want is to have is for the record with game_id 1 should have homeTeamHome pointing to an instance of team with team_id 1 (Team A) and oppTeamHome pointing to an instance of team with team_id 2 (Team B).

So from my facelet page i could reference Team B by #{gameHome.oppTeamHome.instance.team_name} and Team A by #{gameHome.homeTeamHome.instance.team_name}

[christian.bauer]

Do you really need this to be TeamHome components? If you are not editing the Team entity instances, you could just reference them directly in GameHome for display.

[blackers]

I will also be adding new games to the table, The reason I am using the Home components is because this is the way seam gen did it for other table I have generated (they only had single foreign keys to any other table). I would like the option to be able to click a button to add an oponent team to the game and click a button to add a home team to the game, the same way seam gen does it. I will look into a direct reference to the entity from Game Home.

[blackers]

In the end to get it working i duplicated TeamHome.java and renamed the original too.

Now i have HomeTeamHome.java and OppTeamHome.java

with seam names

@Name("homeTeamName")
&
@Name("oppTeamName")

respectively.

With a few changes to TeamList.xhtml, TeamList.page.xml, GameEdit.xhtml and GameEdit.page.xml (based on the versions generated by seam gen) I got the desired result.


GameEdit.page.xml

<param name="oppTeamTeamId" value="#{oppTeamHome.teamTeamId}"/>
<param name="homeTeamTeamId" value="#{homeTeamHome.teamTeamId}"/>

GameEdit.xhtml
(changes in bold/red)

<div class="actionButtons">
 <s:button value="Select Away Team"
 view="/TeamList.xhtml">
 <f:param name="from" value="GameEdit"/>
 <f:param name="forOppTeam" value="1"/>
 </s:button>
 </div>

and

<div class="actionButtons">
 <s:button value="Select Home Team"
 view="/TeamList.xhtml">
 <f:param name="from" value="GameEdit"/>
 <f:param name="forHomeTeam" value="1"/>
 </s:button>
 </div>

TeamList.page.xml

<param name="forOppTeam"/>
<param name="forHomeTeam"/>

TeamList.xhtml

<s:link view="/#{empty from ? 'Team' : from}.xhtml"
 value="#{team.teamName}"
 id="team" rendered="#{not empty forOppTeam}">
 <f:param name="oppTeamTeamId" value="#{team.teamId}"/>
 </s:link>
 <s:link view="/#{empty from ? 'Team' : from}.xhtml"
 value="#{team.teamName}"
 id="team" rendered="#{not empty forHomeTeam}">
 <f:param name="homeTeamTeamId" value="#{team.teamId}"/>
 </s:link>

There is probably a nicer way to do the last block without making 2 separate links and only rendering the appropriate one based on the forXXXXTeam value being used. But my JSF knowledge is pretty minimal at the moment. A rendered attribute for the f:param tag would have been nice.

Thanks for all of your help

[gmarcus]

Why couldn't you use @Role to define 2 known context names for the same component? There is an example in the Seam Docs.

[blackers]

It would be nice that since OppTeamHome.java and HomeTeamHome.java are identical except for the class name and the seam @Name that I would be able to use a single class for both instances.