JList.getModel() ClassCastException
Solution 1
You should not assume it is a DefaultListModel. Use the interface ListModel. The JList is returning an internal implementation of ListModel.
If you need access to the underlying model you should create it, set it in the JList constructor and retain it yourself.
Solution 2
I experienced this issue. I found this simple workaround:
//----instantiation----
JList mList = new JList();
mList.setModel(new DefaultListModel());
/*---- do whatever you want---- */
//Retain it wherever you want with
DefaultListModel model = (DefaultListModel)mList.getModel();
Solution 3
If you are using NetBeans
- Select your jList
- In properties, click the model button
- select the "Custom code" option
- Write
new DefaultListModel ()
Solution 4
Before JList<String>.getModel(),
you must initialize your object JList<String>.setModel(new DefaultModelList())
Stripies
Updated on July 27, 2022Comments
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Stripies almost 2 years
When I call
JList<String>.getModel()
and cast it toDefaultListModel<String>
it gives me this exception.Exception in thread "AWT-EventQueue-0" java.lang.ClassCastException: javax.swing.JList$4 cannot be cast to javax.swing.DefaultListModel
The code that throws it:
private JList<String> list = new JList<String>(); ((DefaultListModel<String>) list.getModel()).addElement(...);
It doesn't do it every time though. Most of the time it works perfectly, but other times it throws this exception. I don't understand why this is happening. Is there anything I can do to stop this from happening?
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jessechk about 11 yearsI had the same problem... Creating it with a new default list model fixes everything. +1
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kleopatra over 10 yearsnothing new compared to one of the earlier answers, is there ;-)
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Willi Mentzel about 10 yearsretaining it is not necessary! see nikola despotoski's answer it is much more efficient!