1.匿名类实现接口的加法器
2.内部类实现接口的加法器
3.本类实现接口
1.匿名类实现接口的加法器
1 package inclass; 2 3 import java.awt.FlowLayout; 4 import java.awt.event.ActionEvent; 5 import java.awt.event.ActionListener; 6 //匿名类类实现接口 7 import javax.swing.*; 8 9 class Add1 extends JFrame implements ActionListener{ 10 JButton jButton = new JButton("="); 11 JLabel jLabel = new JLabel("+"); 12 JTextField j1 = new JTextField(4); 13 JTextField j2 = new JTextField(4); 14 JTextField j3 = new JTextField(4); 15 16 public Add1() { 17 setSize(300,100); 18 setVisible(true); 19 setDefaultCloseOperation(EXIT_ON_CLOSE); 20 setLayout(new FlowLayout()); 21 add(j1); 22 add(jLabel); 23 add(j2); 24 add(jButton); 25 add(j3); 26 validate(); 27 jButton.addActionListener(this); 28 } 29 public void actionPerformed(ActionEvent event) 30 { 31 try { 32 double t1 = Double.parseDouble(j1.getText()); 33 double t2 = Double.parseDouble(j2.getText()); 34 j3.setText(Double.toString(t1+t2)); 35 } 36 catch (NumberFormatException e) { 37 JOptionPane.showMessageDialog(null, e); 38 } 39 } 40 } 41 42 public class Error{ 43 public static void main(String[] args) { 44 new Add1(); 45 } 46 }
2.内部类实现接口的加法器
1 package inclass; 2 import java.awt.FlowLayout; 3 import java.awt.event.ActionEvent; 4 import java.awt.event.ActionListener; 5 //内部类实现接口 6 import javax.swing.*; 7 8 class Add extends JFrame{ 9 JButton jButton = new JButton("="); 10 JLabel jLabel = new JLabel("+"); 11 JTextField j1 = new JTextField(4); 12 JTextField j2 = new JTextField(4); 13 JTextField j3 = new JTextField(4); 14 15 public Add() { 16 setSize(300,100); 17 setVisible(true); 18 setDefaultCloseOperation(EXIT_ON_CLOSE); 19 setLayout(new FlowLayout()); 20 add(j1); 21 add(jLabel); 22 add(j2); 23 add(jButton); 24 add(j3); 25 validate(); 26 jButton.addActionListener(new Tt()); 27 } 28 class Tt implements ActionListener{ 29 public void actionPerformed(ActionEvent event) 30 { 31 try { 32 double t1 = Double.parseDouble(j1.getText()); 33 double t2 = Double.parseDouble(j2.getText()); 34 j3.setText(Double.toString(t1+t2)); 35 } 36 catch (NumberFormatException e) { 37 JOptionPane.showMessageDialog(null, e); 38 } 39 } 40 } 41 } 42 43 44 45 public class Text1 { 46 public static void main(String[] args) { 47 new Add(); 48 } 49 50 }
3.本类实现接口
1 package inclass; 2 import java.awt.FlowLayout; 3 import java.awt.event.ActionEvent; 4 import java.awt.event.ActionListener; 5 //内部类实现接口 6 import javax.swing.*; 7 8 class Add extends JFrame{ 9 JButton jButton = new JButton("="); 10 JLabel jLabel = new JLabel("+"); 11 JTextField j1 = new JTextField(4); 12 JTextField j2 = new JTextField(4); 13 JTextField j3 = new JTextField(4); 14 15 public Add() { 16 setSize(300,100); 17 setVisible(true); 18 setDefaultCloseOperation(EXIT_ON_CLOSE); 19 setLayout(new FlowLayout()); 20 add(j1); 21 add(jLabel); 22 add(j2); 23 add(jButton); 24 add(j3); 25 validate(); 26 jButton.addActionListener(new Tt()); 27 } 28 class Tt implements ActionListener{ 29 public void actionPerformed(ActionEvent event) 30 { 31 try { 32 double t1 = Double.parseDouble(j1.getText()); 33 double t2 = Double.parseDouble(j2.getText()); 34 j3.setText(Double.toString(t1+t2)); 35 } 36 catch (NumberFormatException e) { 37 JOptionPane.showMessageDialog(null, e); 38 } 39 } 40 } 41 } 42 public class Text1 { 43 public static void main(String[] args) { 44 new Add(); 45 } 46 47 }
