import javax.swing.*;
import javax.swing.text.*;
import java.lang.String;
public class JList{
public static void main(String[] args){
JFrame jf = new JFrame("JList");
jf.setSize(300,300);
jf.setLocation(0,0);
jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
jf.setVisible(true);
JPanel pane = new JPanel();
jf.setContentPane(pane);
pane.setLayout(new BorderLayout());
String[] name = {"name1","name2","name3","name4","name5"};
JList name_list = new JList(name);
JTextField jt = new JTextField();
pane.add(name_list,"North");
pane.add(jt,"South");
while(true){
jt.setText((String)name_list.getSelectedValue());
}

}}
JList.java:17: 找不到符号
符号: 构造函数 JList(java.lang.String[])
位置: 类 JList
                JList name_list = new JList(name);
                                  ^
JList.java:19: 找不到符号
符号: 方法 add(JList,java.lang.String)
位置: 类 javax.swing.JPanel
                pane.add(name_list,"North");
                    ^
JList.java:22: 找不到符号
符号: 方法 getSelectedValue()
位置: 类 JList
                        jt.setText((String)name_list.getSelectedValue());
                                                    ^
3 错误想请教下错在哪里了?