To add a user-defined array of choices to a JList in Swing, you can follow these steps:

1. Create a JList instance and a DefaultListModel to hold the data:

JList<String> list = new JList<>();
DefaultListModel<String> model = new DefaultListModel<>();
list.setModel(model);

2. Create an array of choices and populate the DefaultListModel with the array elements:

String[] choices = {"Choice 1", "Choice 2", "Choice 3"};
for (String choice : choices) {
    model.addElement(choice);
}

3. Add the JList to a JScrollPane to enable scrolling if needed:

JScrollPane scrollPane = new JScrollPane(list);

4. Add the JScrollPane or the JList directly to your Swing container:

frame.getContentPane().add(scrollPane); // assuming "frame" is your JFrame instance

By following these steps, you can create a JList with user-defined choices in Swing.