JAVA中對同一問題分別使用內部類與匿名內部類實現

JAVA中對同一問題分別使用內部類與匿名內部類實現，基於輕量級組件Swing中JComboBox組件來舉例說明，希望能夠有助於深入理解內部類與匿名內部類的區別以及其使用。

1. package com.han;  
2. import javax.swing.*;  
3.   
4. import java.awt.*;  
5. import java.awt.event.*;  
6.   
7. /** 
8.  * 設計了一個Swing窗體，其中包括了JComboBox組件(下拉列表框)， 
9.  * 在下面的代碼中運用了內部類的手段。 
10.  * @author HAN 
11.  * 
12.  */  
13. @SuppressWarnings("serial")  
14. public class SwingJComboBox extends JFrame{  
15.   
16.     public SwingJComboBox(){  
17.         setLayout(null);  
18.         setBounds(130,30,300,200);  
19.         Container c=getContentPane();  
20.         final MyComboBox obj1=new MyComboBox();  
21.         @SuppressWarnings({ "unchecked", "rawtypes" })  
22.         JComboBox jc=new JComboBox(obj1);  
23.         jc.setBounds(0,0,290,20);  
24. //      System.out.println(obj1.getElementAt(0));   
25.         jc.addActionListener(new ActionListener(){  
26.             public void actionPerformed(ActionEvent arg0){  
27.                 System.out.println(obj1.getSelectedItem());  
28.             }  
29.         });  
30.         JCheckBox jck1=new JCheckBox("男");  
31.         JCheckBox jck2=new JCheckBox("女",true);  
32.         jck1.setBounds(100,80,40,20);  
33.         jck2.setBounds(140,80,40,20);  
34.         JButton jb1=new JButton("確定");  
35.         JButton jb2=new JButton("取消");  
36.         jb1.setBounds(80,130,60,30);  
37.         jb2.setBounds(140,130,60,30);  
38.         c.add(jc);  
39.         c.add(jck1);  
40.         c.add(jck2);  
41.         c.add(jb1);  
42.         c.add(jb2);  
43.         setVisible(true);  
44.         setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE); //very important !!   
45.     }  
46.       
47.     @SuppressWarnings("rawtypes")  
48.     class MyComboBox extends AbstractListModel implements ComboBoxModel {  
49.         String selecteditem="軍人證";  
50.         String[] test={"身份證","軍人證","學生證"};  
51.         public void setSelectedItem(Object item){  
52.             selecteditem=(String)item;  
53.         }  
54.         public Object getSelectedItem(){  
55.             return selecteditem;  
56.         }  
57.         @Override  
58.         public int getSize() {  
59.             // TODO Auto-generated method stub   
60.             return test.length;  
61.         }  
62.         @Override  
63.         public Object getElementAt(int index) {  
64.             // TODO Auto-generated method stub   
65.             return test[index];  
66.         }  
67.           
68.     }  
69.       
70.     public static void main(String[] args){  
71.         new SwingJComboBox();  
72.           
73.     }  
74. }  

1. package com.han;  
2. import javax.swing.*;  
3. import javax.swing.event.ListDataListener;  
4.   
5. import java.awt.*;  
6. import java.awt.event.*;  
7.   
8. /** 
9.  * 設計了一個Swing窗體，其中包括了JComboBox組件(下拉列表框)， 
10.  * 在下面的代碼中運用了匿名內部類的手段。 
11.  * @author HAN 
12.  * 
13.  */  
14. @SuppressWarnings("serial")  
15. public class SwingJComboBox extends JFrame{  
16.     public static String selectedItem;  
17.     public SwingJComboBox(){  
18.         setLayout(null);  
19.         setBounds(130,30,300,200);  
20.         Container c=getContentPane();  
21. //      final MyComboBox obj1=new MyComboBox();   
22.         @SuppressWarnings({ "unchecked", "rawtypes" })  
23.         JComboBox jc=new JComboBox(new ComboBoxModel(){  
24.             String selecteditem="軍人證";  
25.             String[] test={"身份證","軍人證","學生證"};  
26. //          public void getItem(){   
27. //              selectedItem=selecteditem;   
28. //          }   
29.             @Override  
30.             public int getSize() {  
31.                 // TODO Auto-generated method stub   
32.                 return test.length;  
33.             }  
34.   
35.             @Override  
36.             public Object getElementAt(int index) {  
37.                 // TODO Auto-generated method stub   
38.                 return test[index];  
39.             }  
40.   
41.             @Override  
42.             public void setSelectedItem(Object anItem) {  
43.                 // TODO Auto-generated method stub   
44.                 selecteditem=(String) anItem;  
45.             }  
46.   
47.             @Override  
48.             public Object getSelectedItem() {  
49.                 // TODO Auto-generated method stub   
50. //              getItem();   
51.                 selectedItem=selecteditem;  
52.                 return selecteditem;  
53.             }  
54.   
55.             @Override  
56.             public void addListDataListener(ListDataListener l) {  
57.                 // TODO Auto-generated method stub   
58.                   
59.             }  
60.   
61.             @Override  
62.             public void removeListDataListener(ListDataListener l) {  
63.                 // TODO Auto-generated method stub   
64.                   
65.             }  
66.               
67.         });  
68.         jc.setBounds(0,0,290,20);  
69. //      System.out.println(obj1.getElementAt(0));   
70.         jc.addActionListener(new ActionListener(){  
71.             public void actionPerformed(ActionEvent arg0){  
72.                 System.out.println(selectedItem);  
73.             }  
74.         });  
75.         JCheckBox jck1=new JCheckBox("男");  
76.         JCheckBox jck2=new JCheckBox("女",true);  
77.         jck1.setBounds(100,80,40,20);  
78.         jck2.setBounds(140,80,40,20);  
79.         JButton jb1=new JButton("確定");  
80.         JButton jb2=new JButton("取消");  
81.         jb1.setBounds(80,130,60,30);  
82.         jb2.setBounds(140,130,60,30);  
83.         c.add(jc);  
84.         c.add(jck1);  
85.         c.add(jck2);  
86.         c.add(jb1);  
87.         c.add(jb2);  
88.         setVisible(true);  
89.         setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE); //very important !!   
90.     }  
91.       
92.       
93.     public static void main(String[] args){  
94.         new SwingJComboBox();  
95.           
96.     }  
97. }