Component and Panels - newbie

Question

sometimes panels are directly added and sometimes a Component is created and panels are added to Component and then they are used in JSplitPane.
In what kind of situations can we add directly the panel, and when do we need the Component() ?
eg
final Label l11 = new Label("Sections");
DefaultListModel model = new DefaultListModel();
JList statusList = new JList(model);
model.addElement("Claim Info");
model.addElement("Line Info");
JScrollPane c13 = new JScrollPane(statusList);
Component c11 = new claimspanel();
Component c12 = new claimspanel();
c12.setLayout(new GridLayout(5,1));
clslabelpanel lbl1 = new clslabelpanel();
c12.add(lbl1);
c12.add(c13);
c12.add(Box.createVerticalStrut(100));
c12.add(Box.createVerticalStrut(100));
c12.add(Box.createVerticalStrut(100));
JSplitPane spLeft = new JSplitPane(JSplitPane.VERTICAL_SPLIT, c12, c11);
spLeft.setDividerSize(0);
spLeft.setContinuousLayout(true);

Answer 1

By 'use' i assume you mean, hold the reference as
either a panel or a component.
The answer is you should hold the reference using the type that is most generic, and still meets your needs. In this way, in the future you can adjust the implementation without effecting anyone other code. So if you need a method that is only found in panel, then hold a panel reference. If not, use container if container's methods satisfy you, otherwise use component.