“无法找到符号错误”，即使在使用import语句之后

Question

根据在线教程，我尝试使用Swing在java中创建一个GUI。我试着在网上找一个排水沟，但我找不到。代码如下：

import javax.swing.BorderFactory;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Container;
import javax.swing.GroupLayout;
import javax.swing.GroupLayout.Alignment;
import javax.swing.JLabel;
import javax.swing;

//Create JFrame Container
public class River
{
public River()
{
    JFrame jframe = new JFrame();
    JPanel panel = new JPanel();
    jframe.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    Container contentPanel = jframe.getContentPane();
    GroupLayout grouplayout = new GroupLayout(contentPanel);
    contentPanel.setLayout(grouplayout);

    JLabel clickMe = new JLabel("Click Here");
    JButton button = new JButton("This Button");

    grouplayout.setHorizontalGroup(
        grouplayout.createSequentialGroup()
            .addComponent(clickMe)
            .addGap(10,20,100)
            .addComponent(button));

    grouplayout.setVerticalGroup(
        groupLayout.createParallelGroup(GroupLayout.Alignment.BASELINE)
            .addComponent(clickMe)
            .addComponent(button));

    jframe.setTitle("Our GUI");
    jframe.pack();
    jframe.setVisible(true);
}
public static void main(String[] args) //main method
{
    new River();
} // end of main
}//end River class

但是，当我尝试使用JGraph运行代码时，我会遇到以下错误：

River.java:4:错误：找不到符号导入javax.swing.container；^symbol：类容器位置：包javax.swing River.java:8:错误：包javax不存在，导入javax.swing；^River.java:22:错误：找不到符号容器contentPanel=jframe.getContentPane（）；^symbol：class Container location：class River River.java:27:错误：找不到符号JButton button=new JButton（“this button”）；^symbol：class JButton位置：class River River.java:27:错误：找不到符号JButton button=new JButton（“this button”）；^symbol：class JButton位置：class River River.java:36:错误：找不到符号groupLayout.createParallelGroup（groupLayout.alignment.Baseline）^symbol：variable groupLayout位置：class River 6错误

----jGRASP wedge2: exit code for process is 1.
----jGRASP: operation complete.

任何协助都将不胜感激。

Answer 1

替换

import javax.swing.Container;

与

import java.awt.Container;