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MasterDetailEditor throws NullPointerException when adding new Entity

Kurt Berg
1 decade ago Apr 07, 2012 4:04pm
Abimael Machado
1 decade ago Apr 08, 2012 3:43am

I have the same problem. It´s occur because de method createEntity doesn´t create id for the item. The masterdetaileditor use the itemid to retrieve the item; as has null value the error occur. Look below (red line)
I have a one-to-many relationship with two tables and I don´t know yet how resolve it.

public MasterDetailEditor(FieldFactory fieldFactory,
EntityContainer<?> containerForProperty, Object itemId,
Object propertyId, Component uiContext) {
this.fieldFactory = fieldFactory;
this.containerForProperty = containerForProperty;
this.itemId = itemId;
this.propertyId = propertyId;
masterEntity = containerForProperty.getItem(itemId).getEntity();
boolean writeThrough = true;
if (uiContext instanceof Form) {
Form f = (Form) uiContext;
writeThrough = f.isWriteThrough();



Last updated on Apr, 8th 2012
Kurt Berg
1 decade ago Apr 08, 2012 3:47pm
Sándor Kelemen
1 decade ago Apr 09, 2012 12:14am
Kurt Berg
1 decade ago Apr 12, 2012 6:30am
Erich Reich
1 decade ago Jul 09, 2012 9:08pm
Erich Reich
1 decade ago Jul 11, 2012 11:58pm

I ended up changing the MasterDetailEditor to have the EntityItem as a constructor argument instead of the itemId. This solved my problem. I've attached my class as 'PlasmaDetailEditor'. You'll also have to extend the FieldFactory slightly but that shouldn't be too difficult as the target 'Item' is already present in the createField method.

While I was in the code I also changed the table so the page length goes between 0 -> 5 (but the MAX_PAGE_LENGTH) is a final int at the top of the class. This way the table takes up as little space as possible when it is empty to conserve real estate. If you want a constant size, feel free to comment that out :P


Last updated on Jul, 11th 2012
Mario Giammarco
8 years ago Dec 14, 2014 6:33pm