Colors 类型JList的方法ListSelectionListener（新ListSelectionListener（）{}）未定义

这是一个简单的程序，可以从颜色列表中更改窗格的背景色。但是,

import java.awt.Color;
import java.awt.FlowLayout;             
import javax.swing.JFrame;              
import javax.swing.JTextField;
import java.awt.Font;             
import javax.swing.ButtonGroup;
import javax.swing.JFrame;
import javax.swing.JButton;
import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.JList;
import javax.swing.JOptionPane;
import javax.swing.JCheckBox;
import javax.swing.JScrollPane;
import javax.swing.ListSelectionModel;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import javax.swing.JRadioButton;
import javax.swing.event.ListSelectionListener;

public class JL1st extends JFrame{        

private JList list;
private static String[] colornames = {"black","blue","red","white"};  
private static Color[] colors = {Color.BLACK, Color.BLUE, Color.RED, Color.WHITE};                                


    public JL1st(){
        super("title");       
        setLayout(new FlowLayout());

        list = new JList(colornames);
        list.setVisibleRowCount(4);     
        list.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);       
        add(new JScrollPane(list));    

        list.ListSelectionListener(
                new ListSelectionListener(){
                    public void valueChanged(ListSelectionEvent event){
                     getContentPane().setBackground(colors[list.getSeletedIndex]);  

                        }
                      }
                    );                      
                  }     
                } 

我一直在“ListSelectionListener”上遇到一个错误，类型JList的方法ListSelectionListener（new ListSelectionListener（）{}）未定义 可能是我缺少一个导入，还是只是语法混乱？ 谢谢

问题解决了， ListSelectionListener未导入