百位计算器设计

/*the main calculate function*/   import java.math.*; public class calc {     static calc cal = null;     double result = 1 ;     BigDecimal num1 ;     BigDecimal num2;     BigDecimal value;           /* CONSTRUCTOR*/     private calc(){     }     /*SINGLETON MODLE*/     public static calc  singleton(){         if(cal == null){             cal = new calc();             return cal;         }else{             return cal;         }     }     /* THE ADD OPERTATION*/     public String add(String a , String b){         num1 = new BigDecimal(a);         num2 = new BigDecimal(b);         value = num1.add(num2);         num1 = null;         num2 = null;         return (value.toPlainString());     }     /* THE SUB OPERATION*/     public String sub(String a , String b){         num1 = new BigDecimal(a);         num2 = new BigDecimal(b);         value = num1.subtract(num2);         num1 = null;         num2 = null;         return (value.toPlainString());     }     /* THE MULTIPLY OPERATION*/     public String multiply(String a , String b){         num1 = new BigDecimal(a);         num2 = new BigDecimal(b);         value = num1.multiply(num2);         num1 = null;         num2 = null;         return (value.toPlainString());     }     /* THE DIV OPERATION*/     public String div(String a , String b){         num1 = new BigDecimal(a);         num2 = new BigDecimal(b);         value = num1.divide(num2,100,BigDecimal.ROUND_HALF_UP);         num1 = null;         num2 = null;         return (value.toPlainString());     }     /* THE ROOT OPERATION*/     public String root(String a){                   return Math.sqrt(Double.parseDouble(a))+"";               }     /* THE FACTORIAL OPERATION阶乘*/     public double factorial(Double a){         for(int i = 1 ; i<=a ; i++){             result = result*i;         }         return result;               }     /* THE SQUARE OPERATION*/     public String square(String d){         num1 = new BigDecimal(d);         value = num1.multiply(num1);         num1 = null;         return (value.toPlainString());     }     /*THE CUBIC OPERATION*/     public String cubic(String a){         num1 = new BigDecimal(a);         value = num1.multiply(num1);         value = value.multiply(num1);         num1 = null;         return (value.toPlainString());     }     /* THE POWER OPERATION幂次*/     public String power(String a , int e){         num1 = new BigDecimal(a);         value = num1.pow(e);         num1 = null;         return value.toPlainString();     }     /*THE RECIPROCAL OPERATION倒数*/     public String reciprocal(String a){         num1 = new BigDecimal("1.0");         num2 = new BigDecimal(a);         value = num1.divide(num2,100,BigDecimal.ROUND_HALF_UP);         num1 = null;         num2 = null;         return value.toPlainString();     }           public String mod(String a, String b){         num1 = new BigDecimal(a);         num2 = new BigDecimal(b);         value = num1.remainder(num2);         num1 = null;         num2 = null;         return value.toPlainString();     } }       /* the main implements function*/     import java.awt.*; import java.awt.event.*; @SuppressWarnings("serial") public class myframe extends Frame {           TextField text = null;           /*THE CONSTRUCTOR */     public myframe(String topic , int x , int y , int height , int width){         super(topic);         this.setVisible(true);         this.addWindowListener(new windowmonitor());         this.setBounds(x,y,height,width);         this.setResizable(false);     }           /*THE WINDOW MONITOR WHICH IS USED TO CLOSE THE WINDOW*/     class windowmonitor extends WindowAdapter {         public void windowClosing(WindowEvent e){             setVisible(false);             System.exit(0);         }     }           /*THE SINGLETON MODEL*/     static myframe one = new myframe("calculator" , 200 , 200 , 400 , 350);     public static myframe getme(){         return one;     }           public static void main(String args[]){         /*it is used to screen the number*/         Panel panel1 = new Panel();         /*it is used to contain the button */         Panel panel2 = new Panel();                   panel2.setLayout(new BorderLayout());         panel1.setBounds(0,100,400,240);         panel2.setBounds(200,200,400,125);         panel1.setBackground(Color.GREEN);         panel2.setBackground(Color.BLUE);         panel1.setLayout(new GridLayout(5,5,5,5));         one.add(panel1);         one.add(panel2);         myframe.getme().text = new TextField(50);         panel2.add(myframe.getme().text);         myframe.getme().text.setBackground(Color.PINK);                   /*THE BUTTONS , I THINK WE CAN USE ARRAY TO IMPLEMENTS THIS FUNCTION  */         Button button1 = new Button("1");         Button button2 = new Button("2");         Button button3 = new Button("3");         Button button4 = new Button("4");         Button button5 = new Button("5");         Button button6 = new Button("6");         Button button7 = new Button("7");         Button button8 = new Button("8");         Button button9 = new Button("9");         Button button10 = new Button("0");         Button button11 = new Button("+");         Button button12= new Button("-");         Button button13= new Button("*");         Button button14= new Button("/");         Button button15= new Button("cubic");         Button button16= new Button("square");         Button button17= new Button("root");         Button button18= new Button("factorial");         Button button19= new Button("reciprocal");         Button button20= new Button("power");         Button button21= new Button(".");         Button button22= new Button("=");         Button button23= new Button("clc");         Button button24= new Button("mod"); /*              Button button25= new Button();         Button button26= new Button();         Button button27= new Button();         Button button28= new Button();         Button button29= new Button();         Button button30= new Button(); */         /*THE ADD THE BUTTONS TO THE PANEL*/         panel1.add(button1);         panel1.add(button2);         panel1.add(button3);         panel1.add(button4);         panel1.add(button5);         panel1.add(button6);         panel1.add(button7);         panel1.add(button8);         panel1.add(button9);         panel1.add(button10);         panel1.add(button11);         panel1.add(button12);         panel1.add(button13);         panel1.add(button14);         panel1.add(button15);         panel1.add(button16);         panel1.add(button17);         panel1.add(button18);         panel1.add(button19);         panel1.add(button20);         panel1.add(button21);         panel1.add(button22);         panel1.add(button23);         panel1.add(button24); /*                   panel1.add(button25);         panel1.add(button26);         panel1.add(button27);         panel1.add(button28);         panel1.add(button29);         panel1.add(button30); */         /*ADD MONITOR TO THE BUTTON*/         monitor mymonitor = new monitor();         button1.addActionListener(mymonitor);         button2.addActionListener(mymonitor);         button3.addActionListener(mymonitor);         button4.addActionListener(mymonitor);         button5.addActionListener(mymonitor);         button6.addActionListener(mymonitor);         button7.addActionListener(mymonitor);         button8.addActionListener(mymonitor);         button9.addActionListener(mymonitor);         button10.addActionListener(mymonitor);         button11.addActionListener(mymonitor);         button12.addActionListener(mymonitor);         button13.addActionListener(mymonitor);         button14.addActionListener(mymonitor);         button15.addActionListener(mymonitor);         button16.addActionListener(mymonitor);         button17.addActionListener(mymonitor);         button18.addActionListener(mymonitor);         button19.addActionListener(mymonitor);         button20.addActionListener(mymonitor);         button21.addActionListener(mymonitor);         button22.addActionListener(mymonitor);         button23.addActionListener(mymonitor);         button24.addActionListener(mymonitor);     }       }   /*THE MONITOR WHICH IS USED TO IMPLEMENT THE FUNCTION OF A CALCULATOR*/ class monitor implements ActionListener{           String command = null;     String str1 = null;     String str2 = null;     TextField text1 =null;     String backvalue = null;           /*THE FLAG WHICH IS USED TO DISTINGUISH THE FUNCTION*/     int flag = -1;           @Override     public void actionPerformed(ActionEvent e) {         /*GET THE INFORMATION OF THE TEXT*/         text1 = myframe.getme().text;         str1 = text1.getText();         /*RETURN THE COMMAND OF THE BUTTON*/         command = e.getActionCommand();         /*TO SCREEN THE NUMBER */         if(command.equals("0")||command.equals("1")||command.equals("2")||command.equals("3")                 ||command.equals("4")||command.equals("5")||command.equals("6")||command.equals("7")                 ||command.equals("8")||command.equals("9")||command.equals(".")){             text1.setText(str1+command);             /*PLUS FUNCTION*/         }else if(command.equals("+")){             backvalue = str1;             text1.setText("");             flag = 0;             /*THE MINUS FUNCTION*/         }else if(command.equals("-")){             backvalue = str1;             text1.setText("");             flag = 1;             /*THE MUTIPLY FUNCTION*/         }else if(command.equals("*")){             backvalue = str1;             text1.setText("");             flag = 2;             /*THE DEVIDE FUNCTION*/         }else if(command.equals("/")){             backvalue = str1;             text1.setText("");             flag = 3;             /*THE CUBIC FUNCTION*/         }else if(command.equals("cubic")){             backvalue = str1;             text1.setText("");             flag = 4;             /*THE SQUARE FUNCTION*/         }else if(command.equals("square")){             backvalue = str1;             text1.setText("");             flag = 5;             /*THE ROOT FUNCTION*/         }else if(command.equals("root")){             backvalue = str1;             text1.setText("");             flag = 6;             /*THE FACTORIAL FUNCTION*/         }else if(command.equals("factorial")){             backvalue = str1;             text1.setText("");             flag = 7;             /*THE RECIPROCAL FUNCTION*/         }else if(command.equals("reciprocal")){             backvalue = str1;             text1.setText("");             flag = 8;             /*THE POWER FUNCTION*/         }else if(command.equals("power")){             backvalue = str1;             text1.setText("");             flag = 9;             /*TO DELETE THE CHAR WHICH IS SHOWED IN THE TEXT*/         }else if(command.equals("mod")){             text1.setText("");             text1.setText("");             flag = 10;         }else if(command.equals("clc")){             text1.setText("");             backvalue = "";             flag = -1;             /*IMPLEMENTS THE FUNCTION*/         }else if(command.equals("=")){                           switch(flag){             case 0: str1 = text1.getText();                     backvalue = calc.singleton().add(backvalue, str1);                     flag =-1;                     break;             case 1:str1 = text1.getText();                    backvalue = calc.singleton().sub(backvalue, str1);                    flag =-1;                    break;             case 2:str1 = text1.getText();                    backvalue = calc.singleton().multiply(backvalue, str1);                    flag =-1;                    break;             case 3:str1 = text1.getText();                    backvalue = calc.singleton().div(backvalue, str1);                    flag =-1;                    break;             case 4:str1 = text1.getText();                    backvalue = calc.singleton().cubic(backvalue);                    flag =-1;                    break;             case 5:str1 = text1.getText();                    backvalue = calc.singleton().square(backvalue);                    flag =-1;                    break;             case 6:str1 = text1.getText();                    backvalue = calc.singleton().root(backvalue);                    flag =-1;                    break;             case 7:str1 = text1.getText();                    backvalue = ""+calc.singleton().factorial(Double.parseDouble(backvalue));                    flag =-1;                    break;             case 8:str1 = text1.getText();                    backvalue = calc.singleton().reciprocal(backvalue);                    flag =-1;                    break;             case 9:str1 = text1.getText();                    backvalue = calc.singleton().power(backvalue, Integer.parseInt(str1));                    flag =-1;                    break;             case 10:str1 = text1.getText();                     backvalue = calc.singleton().mod(backvalue,str1);                     flag =-1;                     break;             }              text1.setText(""+backvalue);         }     } }