java 计算器编码

1. import java.awt.*;
   
2. import java.awt.event.*;
   
3. import java.lang.*;
   
4. import javax.swing.*;
   
5. public class ccextends Frame{
   
6.     //声明三个面板的布局
   
7. 
   
8.     GridLayout gl1,gl2,gl3;
   
9.     Panel p0,p1,p2,p3;
   
10.     JTextField tf1;
    
11.     TextField tf2;
    
12.     Button b0,b1,b2,b3,b4,b5,b6,b7,b8,b9,b10,b11,
    
13.     b12,b13,b14,b15,b16,b17,b18,
    
14.     b19,b20,b21,b22,b23,b24,b25,b26;
    
15.     StringBuffer str;
    
16.     //显示屏所显示的字符串
    
17. 
    
18.     double x,y;
    
19.     //x和y都是运算数
    
20. 
    
21.     int z;
    
22.     //Z表示单击了那一个运算符.0表示"+",1表示"-",2表示"*",3表示"/"
    
23. 
    
24.     static double m;
    
25.     //记忆的数字
    
26. 
    
27.     public cc(){
    
28.         gl1=newGridLayout(1,4,10,0);
    
29.         //实例化三个面板的布局
    
30. 
    
31.         gl2=newGridLayout(4,1,0,15);
    
32.         gl3=newGridLayout(4,5,10,15);
    
33.         tf1=newJTextField(27);
    
34.         //显示屏
    
35. 
    
36.         tf1.setHorizontalAlignment(JTextField.RIGHT);
    
37.         tf1.setEnabled(false);
    
38.         tf1.setText("0");
    
39.         tf2=newTextField(10);
    
40.         //显示记忆的索引值
    
41. 
    
42.         tf2.setEditable(false);
    
43.         //实例化所有按钮、设置其前景色并注册监听器
    
44. 
    
45.         b0=newButton("Backspace");
    
46.         b0.setForeground(Color.red);
    
47.         b0.addActionListener(new Bt());
    
48.         b1=newButton("CE");
    
49.         b1.setForeground(Color.red);
    
50.         b1.addActionListener(new Bt());
    
51.         b2=newButton("C");
    
52.         b2.setForeground(Color.red);
    
53.         b2.addActionListener(new Bt());
    
54.         b3=newButton("MC");
    
55.         b3.setForeground(Color.red);
    
56.         b3.addActionListener(new Bt());
    
57.         b4=newButton("MR");
    
58.         b4.setForeground(Color.red);
    
59.         b4.addActionListener(new Bt());
    
60.         b5=newButton("MS");
    
61.         b5.setForeground(Color.red);
    
62.         b5.addActionListener(new Bt());
    
63.         b6=newButton("M+");
    
64.         b6.setForeground(Color.red);
    
65.         b6.addActionListener(new Bt());
    
66.         b7=newButton("7");
    
67.         b7.setForeground(Color.blue);
    
68.         b7.addActionListener(new Bt());
    
69.         b8=newButton("8");
    
70.         b8.setForeground(Color.blue);
    
71.         b8.addActionListener(new Bt());
    
72.         b9=newButton("9");
    
73.         b9.setForeground(Color.blue);
    
74.         b9.addActionListener(new Bt());
    
75.         b10=newButton("/");
    
76.         b10.setForeground(Color.red);
    
77.         b10.addActionListener(new Bt());
    
78.         b11=newButton("sqrt");
    
79.         b11.setForeground(Color.blue); b11.addActionListener(new Bt());
    
80.         b12=newButton("4"); b12.setForeground(Color.blue); b12.addActionListener(new Bt());
    
81.         b13=newButton("5"); b13.setForeground(Color.blue); b13.addActionListener(new Bt());
    
82.         b14=newButton("6"); b14.setForeground(Color.blue); b14.addActionListener(new Bt());
    
83.         b15=newButton("*"); b15.setForeground(Color.red); b15.addActionListener(new Bt());
    
84.         b16=newButton("%"); b16.setForeground(Color.blue); b16.addActionListener(new Bt());
    
85.         b17=newButton("1"); b17.setForeground(Color.blue); b17.addActionListener(new Bt());
    
86.         b18=newButton("2"); b18.setForeground(Color.blue); b18.addActionListener(new Bt());
    
87.         b19=newButton("3"); b19.setForeground(Color.blue); b19.addActionListener(new Bt());
    
88.         b20=newButton("-"); b20.setForeground(Color.red); b20.addActionListener(new Bt());
    
89.         b21=newButton("1/X"); b21.setForeground(Color.blue); b21.addActionListener(new Bt());
    
90.         b22=newButton("0"); b22.setForeground(Color.blue); b22.addActionListener(new Bt());
    
91.         b23=newButton("+/-"); b23.setForeground(Color.blue); b23.addActionListener(new Bt());
    
92.         b24=newButton("."); b24.setForeground(Color.blue); b24.addActionListener(new Bt());
    
93.         b25=newButton("+"); b25.setForeground(Color.red); b25.addActionListener(new Bt());
    
94.         b26=newButton("="); b26.setForeground(Color.red); b26.addActionListener(new Bt());
    
95.         //实例化四个面板
    
96. 
    
97.         p0=newPanel();
    
98.         p1=newPanel();
    
99.         p2=newPanel();
    
100.         p3=newPanel();
     
101.         //创建一个空字符串缓冲区
     
102. 
     
103.         str=newStringBuffer();
     
104.         //添加面板p0中的组件和设置其在框架中的位置和大小
     
105. 
     
106.         p0.add(tf1);
     
107.         p0.setBounds(10,25,300,40);
     
108.         //添加面板p1中的组件和设置其在框架中的位置和大小
     
109. 
     
110.         p1.setLayout(gl1);
     
111.         p1.add(tf2);
     
112.         p1.add(b0); p1.add(b1); p1.add(b2);
     
113.         p1.setBounds(10,65,300,25);
     
114.         //添加面板p2中的组件并设置其的框架中的位置和大小
     
115. 
     
116.         p2.setLayout(gl2); p2.add(b3); p2.add(b4);
     
117.         p2.add(b5); p2.add(b6); p2.setBounds(10,110,40,150);
     
118.         //添加面板p3中的组件并设置其在框架中的位置和大小
     
119. 
     
120.         p3.setLayout(gl3);//设置p3的布局
     
121. 
     
122.         p3.add(b7); p3.add(b8); p3.add(b9); p3.add(b10);
     
123.         p3.add(b11); p3.add(b12); p3.add(b13); p3.add(b14);
     
124.         p3.add(b15); p3.add(b16); p3.add(b17); p3.add(b18);
     
125.         p3.add(b19); p3.add(b20); p3.add(b21); p3.add(b22);
     
126.         p3.add(b23); p3.add(b24); p3.add(b25); p3.add(b26);
     
127.         p3.setBounds(60,110,250,150);
     
128.         //设置框架中的布局为空布局并添加4个面板
     
129. 
     
130.         setLayout(null);add(p0);add(p1);add(p2);
     
131.         add(p3);setResizable(false);
     
132.         //禁止调整框架的大小 //匿名类关闭窗口
     
133. 
     
134.         addWindowListener(newWindowAdapter(){
     
135.             public void windowClosing(WindowEvent e1){
     
136.                 System.exit(0);
     
137.                 }
     
138.             });
     
139.         setBackground(Color.lightGray);
     
140.         setBounds(100,100,320,280);
     
141.         setVisible(true);}
     
142.     //构造监听器
     
143. 
     
144.     class Bt implementsActionListener {
     
145.         public void actionPerformed(ActionEvent e2){
     
146.             try{
     
147.                 if(e2.getSource()==b1)
     
148.                     //选择"CE"清零
     
149. 
     
150.                     { tf1.setText("0");
     
151.                     //把显示屏清零
     
152. 
     
153.                     str.setLength(0);
     
154.                     //清空字符串缓冲区以准备接收新的输入运算数
     
155. 
     
156.                     } else if(e2.getSource()==b2)
     
157.                         //选择"C"清零
     
158. 
     
159.                         { tf1.setText("0");
     
160.                         //把显示屏清零
     
161. 
     
162.                         str.setLength(0);
     
163.                         } else if(e2.getSource()==b23)
     
164.                             //单击"+/-"选择输入的运算数是正数还是负数
     
165. 
     
166.                             { x=Double.parseDouble(tf1.getText().trim());
     
167.                             tf1.setText(""+(-x));} else if(e2.getSource()==b25)
     
168.                                 //单击加号按钮获得x的值和z的值并清空y的值
     
169. 
     
170.                                 {
     
171.                                 x=Double.parseDouble(tf1.getText().trim());
     
172.                                 str.setLength(0);
     
173.                                 //清空缓冲区以便接收新的另一个运算数
     
174. 
     
175.                                 y=0d; z=0;} else if(e2.getSource()==b20)
     
176.                                     //单击减号按钮获得x的值和z的值并清空y的值
     
177. 
     
178.                                     { x=Double.parseDouble(tf1.getText().trim());
     
179.                                     str.setLength(0); y=0d; z=1; } else if(e2.getSource()==b15)
     
180.                                         //单击乘号按钮获得x的值和z的值并清空y的值
     
181. 
     
182.                                         { x=Double.parseDouble(tf1.getText().trim()); str.setLength(0); y=0d; z=2; }
     
183.                                     else if(e2.getSource()==b10)//单击除号按钮获得x的值和z的值并空y的值
     
184. 
     
185.                                         { x=Double.parseDouble(tf1.getText().trim()); str.setLength(0); y=0d; z=3; }
     
186.                                     else if(e2.getSource()==b26)//单击等号按钮输出计算结果
     
187. 
     
188.                                         { str.setLength(0);switch(z){ case 0 : tf1.setText(""+(x+y));
     
189.                                         break;case 1 : tf1.setText(""+(x-y));break;case 2 : tf1.setText(""+(x*y));break;
     
190.                                         case 3: tf1.setText(""+(x/y));break;} } else if(e2.getSource()==b24)
     
191.                                             //单击"."按钮输入小数
     
192. 
     
193.                                             {if(tf1.getText().trim().indexOf(".")!=-1)
     
194.                                                 //判断字符串中是否已经包含了小数点
     
195. 
     
196.                                                 {} else//如果没数点有小
     
197. 
     
198.                                                     {if(tf1.getText().trim().equals("0"))
     
199.                                                         //如果初时显示为0
     
200. 
     
201.                                                         { str.setLength(0);
     
202.                                                         tf1.setText((str.append("0"+e2.getActionCommand())).toString());}
     
203.                                                     elseif(tf1.getText().trim().equals(""))
     
204.                                                         //如果初时显示为空则不做任何操作
     
205. 
     
206.                                                         {} else { tf1.setText(str.append(e2.getActionCommand()).toString());}
     
207.                                                     } y=0d;} else if(e2.getSource()==b11)
     
208.                                                         //求平方根
     
209. 
     
210.                                                         { x=Double.parseDouble(tf1.getText().trim());
     
211.                                                         tf1.setText("数字格式异常");
     
212.                                                         if(x<0) tf1.setText("负数没有平方根");
     
213.                                                         else tf1.setText(""+Math.sqrt(x)); str.setLength(0); y=0d;}
     
214.                                                     elseif(e2.getSource()==b16)//单击了"%"按钮
     
215. 
     
216.                                                         { x=Double.parseDouble(tf1.getText().trim());
     
217.                                                         tf1.setText(""+(0.01*x)); str.setLength(0); y=0d;
     
218.                                                         }else if(e2.getSource()==b21)//单击了"1/X"按钮
     
219. 
     
220.                                                             { x=Double.parseDouble(tf1.getText().trim());
     
221.                                                             if(x==0){ tf1.setText("除数不能为零");} else
     
222.                                                             { tf1.setText(""+(1/x));} str.setLength(0); y=0d;
     
223.                                                             }else if(e2.getSource()==b3)//MC为清除内存
     
224. 
     
225.                                                                 { m=0d; tf2.setText(""); str.setLength(0);
     
226.                                                                 }else if(e2.getSource()==b4)//MR为重新调用存储的数据
     
227. 
     
228.                                                                     {if(tf2.getText().trim()!="")//有记忆数字
     
229. 
     
230.                                                                         { tf1.setText(""+m);} } else if(e2.getSource()==b5)
     
231.                                                                             //MS为存储显示的数据
     
232. 
     
233.                                                                             { m=Double.parseDouble(tf1.getText().trim());
     
234.                                                                             tf2.setText("M"); tf1.setText("0"); str.setLength(0);}
     
235.                                                                         elseif(e2.getSource()==b6)//M+为将显示的数字与已经存储的数据相加要查看新的数字单击MR
     
236. 
     
237.                                                                             { m=m+Double.parseDouble(tf1.getText().trim());} else//选择的是其他的按钮
     
238. 
     
239.                                                                                 {if(e2.getSource()==b22)//如果选择的是"0"这个数字键
     
240. 
     
241.                                                                                     {if(tf1.getText().trim().equals("0"))
     
242.                                                                                         //如果显示屏显示的为零不做操作
     
243. 
     
244.                                                                                         {} else { tf1.setText(str.append(e2.getActionCommand()).toString());
     
245.                                                                                         y=Double.parseDouble(tf1.getText().trim());} } else if(e2.getSource()==b0)
     
246.                                                                                             //选择的是“BackSpace”按钮
     
247. 
     
248.                                                                                             {if(!tf1.getText().trim().equals("0"))
     
249.                                                                                             //如果显示屏显示的不是零
     
250. 
     
251.                                                                                                 {if(str.length()!=1){
     
252.                                                                                                     tf1.setText(str.delete(str.length()-1,str.length()).toString());
     
253.                                                                                                     //可能抛出字符串越界异常
     
254. 
     
255.                                                                                                     }else { tf1.setText("0"); str.setLength(0);} }
     
256.                                                                                             y=Double.parseDouble(tf1.getText().trim());} else
     
257.                                                                                                 //其他的数字键
     
258. 
     
259.                                                                                                 { tf1.setText(str.append(e2.getActionCommand()).toString());
     
260.                                                                                                 y=Double.parseDouble(tf1.getText().trim());} } } catch(NumberFormatException e){ tf1.setText("数字格式异常");} catch(StringIndexOutOfBound***ception e)
     
261.                                                                             { tf1.setText("字符串索引越界");} } } public staticvoid main(String args[]){ new cc();} }