JTree + FK with same value causing problems

Question

Hi
I can't figure this out. If I create biz components for 2 tables having a parent-child relationship and a jTree with appropriate rules, things are ok only if the parent's id are of different values than the child. When parent.id and child.id have the same values the jTree seems to recursively fire valueChanged() at strange times.
Example:
CREATE TABLE PARENT
PARENT_ID NUMBER CONSTRAINT PARENT_ID_NN NOT NULL,
PARENT_NAME VARCHAR2(40 BYTE),
CONSTRAINT PARENT_C_ID_PK
PRIMARY KEY
(PARENT_ID)
CREATE TABLE CHILD
CHILD_ID NUMBER CONSTRAINT CHILD_ID_NN NOT NULL,
CHILD_NAME VARCHAR2(40 BYTE),
PARENT_ID NUMBER,
CONSTRAINT CHILD_C_ID_PK
PRIMARY KEY
(CHILD_ID)
ALTER TABLE CHILD ADD (
CONSTRAINT PARENT_FK
FOREIGN KEY (PARENT_ID)
REFERENCES PARENT (PARENT_ID));
INSERT INTO PARENT VALUES (1, 'Parent 1');
INSERT INTO PARENT VALUES (2, 'Parent 2');
INSERT INTO PARENT VALUES (3, 'Parent 3');
INSERT INTO CHILD VALUES (100, 'Child A', 1);
INSERT INTO CHILD VALUES (200, 'Child B', 2);
INSERT INTO CHILD VALUES (300, 'Child C', 3);
I use the JDev 10.1.2 wizard to create biz components and test the AppMod to make sure the link works. Now I create a blank panel and drag over the ParentView data control. Using the jTree tree binding editor I create two rules:
1) DataCollectionDef.ParentView - DisplayAttribute.ParentName - BranchRuleAccessor.ChildView
2) DataCollectionDef.ChildView - DisplayAttribute.ChildName
Now I add a tree selection listener:
jTree1.addTreeSelectionListener(new TreeSelectionListener()
public void valueChanged(TreeSelectionEvent e)
DefaultMutableTreeNode selectedNode = (DefaultMutableTreeNode)jTree1.getLastSelectedPathComponent();
if (selectedNode != null)
System.out.println(selectedNode.getUserObject().toString());
When I run my panel and watch in JDev everything is fine, i.e. nothing is printed to the screen when it first loads and when I click a node, the correct UserObject prints.
Here's the rub, now I close the panel and update my child table as follows:
UPDATE pdssuser.child SET child_id = 1 WHERE child_id = 100;
UPDATE pdssuser.child SET child_id = 2 WHERE child_id = 200;
UPDATE pdssuser.child SET child_id = 3 WHERE child_id = 300;
This time, when I run my panel, the console shows that valueChanged() has been fired 3 times on load:
Parent 1
Parent 2
Parent 3
This behavior is causing problems with my real tree.
I haven't had any luck finding threads about this. Any ideas?
Thanks
John

Answer 1

ok, last one (i hope)
The same issue occurs with 10.1.2.1
...but changing the location where I add the treeSelectionListener to after setBindingContext() seems to fix the problem.
The second call to panelBinding.refreshControl() in setBindingContext() (the one after the call to jbinit()) is what fires the valueChanged events. Somewhere in there, DCBindingContainer.java or DCIteratorBinding.java, the treeSelectionListener is hearing that a value changed (maybe due to a query execution?). I guess the jTree1.setModel(...) call in jbinit() simply sets up the tree but the VO queries described in the Branch Rule accessors are executed on the refreshControl.....i'm out of my comfort zone here and may be confusing you with my "troubleshooting" so I'll just tell you my work-around.
So to fix it I add the treeSelectionListener in my main method (not jbinit()) after the setBindingContext() has been called.
I still have no idea why the FK triggers this behavior...but at least it's working.
* the main method
public static void main(String [] args)
try
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
catch(Exception exemp)
exemp.printStackTrace();
Panel1 panel = new Panel1();
panel.setBindingContext(JUTestFrame.startTestFrame("DataBindings.cpx", "null", panel, panel.getPanelBinding(), new Dimension(400, 300)));
panel.revalidate();
// Now add the treeSelectionListener
panel.addSelectionListener();
* the JbInit method
public void jbInit() throws Exception
this.setLayout(borderLayout1);
this.add(jTree1, BorderLayout.CENTER);
jTree1.setModel((TreeModel)panelBinding.bindUIControl("ParentView1", jTree1));
// DON'T ADD treeSelectionListener here
* Add the selection listener to the tree
public void addSelectionListener()
jTree1.addTreeSelectionListener(new TreeSelectionListener()
public void valueChanged(TreeSelectionEvent e)
DefaultMutableTreeNode selectedNode = (DefaultMutableTreeNode)jTree1.getLastSelectedPathComponent();
if (selectedNode != null)
System.out.println(selectedNode.getUserObject().toString());
}