import java.awt.*; import javax.swing.*; public class JSplitPaneTest extends JFrame { JSplitPaneTest() { String[] data = { "A", "B", "C" }; JTree tree = new JTree(); JList list = new JList(data); JSplitPane splitPane = new JSplitPane(); splitPane.setDividerSize(5); splitPane.setLeftComponent(tree); splitPane.setRightComponent(list); getContentPane().add(splitPane); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); setTitle("JSplitPaneTest"); setSize(200, 150); setVisible(true); } public static void main(String[] args) { new JSplitPaneTest(); } }