java编程，用代码实现计算器类（Calculator）

Question

（1）定义成员变量运算数1（number1）和运算数2（number2）。
（2）定义成员方法“加”（add）、“减”（subtract）、“乘”（multiple）、“除”（divide）。
（3）定义测试类Test，对任意数进行加、减、乘、除运算。

Answer 1

public class Calculator {
private int number1;
private int number2;
public Calculator(int number1, int number2) {
this.number1 = number1;
this.number2 = number2;
}

public double add() {
return number1 + number2;
}

public double subtract() {
return number1 - number2;
}

public double multiple() {
return number1 * number2;
}

public double divide() {
if(number2 == 0) {
return 0;
}
return number1 / number2;
}
}

public class TestCalculator {
public static void main(String[] args) {
Calculator calculator = new Calculator(5, 2);
System.out.println(calculator.add());
System.out.println(calculator.subtract());
System.out.println(calculator.multiple());
System.out.println(calculator.divide());
}
}

Answer 2

import java.awt.Container;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JTextField;

public class TestC {
public static void main(String[] args) {
IFrame frame = new IFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.show();
}
}

class IFrame extends JFrame {
public static final int width = 200;

public static final int height = 200;

public IFrame() {
setTitle("Welcome");
setSize(width, height);
IPanels panel = new IPanels();
Container ContentPane = getContentPane();
ContentPane.add(panel);
}
}

class IPanels extends JPanel implements ActionListener {
JLabel res;
JTextField num1;
JTextField num2;
JButton addbtn;
JButton subductionbtn;
JButton multiplybtn;
JButton divisionbtn;
public IPanels() {
setLayout(new FlowLayout(FlowLayout.LEFT));
res = new JLabel("结果: 0");
JLabel la1 = new JLabel("输入整数a:");
JLabel la2 = new JLabel("输入整数b:");
addbtn = new JButton("+");
subductionbtn = new JButton("—");
multiplybtn = new JButton("*");
divisionbtn = new JButton("/");
num1 = new JTextField(10);
num2 = new JTextField(10);

add(la1);
add(num1);
add(la2);
add(num2);
add(addbtn);
add(subductionbtn);add(multiplybtn);add(divisionbtn);
add(res);
addbtn.addActionListener(this);
subductionbtn.addActionListener(this);
multiplybtn.addActionListener(this);
divisionbtn.addActionListener(this);

}

public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
if(e.getSource()==addbtn){
res.setText(String.valueOf(Integer.parseInt(num1.getText())+Integer.parseInt(num2.getText())));
}else if(e.getSource()==subductionbtn){
res.setText(String.valueOf(Integer.parseInt(num1.getText())-Integer.parseInt(num2.getText())));
}else if(e.getSource()==multiplybtn){
res.setText(String.valueOf(Integer.parseInt(num1.getText())*Integer.parseInt(num2.getText())));
}else if(e.getSource()==divisionbtn){
res.setText(String.valueOf(Integer.parseInt(num1.getText())/Integer.parseInt(num2.getText())));
}
}

}

Answer 3

package ch01;
public class CalcTest {
public static float number1,number2;
public static void main(String[] args) {
number1=10;
number2=15;
System.out.println(add());
System.out.println(subtract());
System.out.println(multiple());
System.out.println(divide());
}

public static float add(){
return number1+number2;
}
public static float subtract(){
return number1-number2;
}
public static float multiple(){
return number1*number2;
}
public static float divide(){
if(number2==0)
return -1;
return number1/number2;
}
}

Answer 4

你会不会啊？

Answer 5

名字怎么弄啊脱突