Here is an example that shows the selected value from the jlist to textfield.

import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
import javax.swing.event.*;

public class ListAction extends JPanel implements ListSelectionListener {
JList list;
DefaultListModel listModel;
JTextField nameField;
public ListAction() {
super(new BorderLayout());
listModel = new DefaultListModel();
listModel.addElement("ZEN");
listModel.addElement("Alto");
listModel.addElement("Swift");
listModel.addElement("Centro");
listModel.addElement("Innova");
listModel.addElement("Scorpio");
listModel.addElement("Chevrolet");
listModel.addElement("Honda City");
list = new JList(listModel);
list.setSelectionMode(ListSelectionModel.SINGLE_INTERVAL_SELECTION);
list.setSelectedIndex(0);
list.addListSelectionListener(this);
JScrollPane listScrollPane = new JScrollPane(list);

nameField = new JTextField(15);
String name = listModel.getElementAt(list.getSelectedIndex()).toString();
nameField.setText(name);
JPanel panel = new JPanel();
panel.add(nameField);
JSplitPane splitPane = new JSplitPane(JSplitPane.VERTICAL_SPLIT, panel,listScrollPane);
splitPane.setResizeWeight(0.5);
add(splitPane, BorderLayout.CENTER);
}
public void valueChanged(ListSelectionEvent e) {
if (e.getValueIsAdjusting() == false) {
if (list.getSelectedIndex() == -1) {
nameField.setText("");

}else if (list.getSelectedIndices().length > 1) {
} else {
nameField.setText(list.getSelectedValue().toString());
}
}
}
public static void main(String[] args) {
JFrame frame = new JFrame("Clear ListData");
JComponent component = new ListAction();
component.setOpaque(true);
frame.setContentPane(component);
component.setMinimumSize(new Dimension(component.getPreferredSize().width, 100));
frame.pack();
frame.setVisible(true);
}
}