Four arithmetic testing and encapsulation (improved) 5.2 5.3

A pair of Friends: Chen Shu-yun http://www.cnblogs.com/babybluecsj/

II. (1) I used my friend's last 5.1 job for unit testing. I found that when the divisor is zero, no exception was thrown during the operation, so we added

   1.     if(fh2==‘/‘){

             if (b== 0 ){                  throw  new  Exception( "The divisor cannot be 0! " );              }              answer=a/b;          }2.   try  {               res=Calculator.Onefhnum( 1 , 1 , 3 );                        }  catch  (Exception e) {              e.printStackTrace();              Assert.fail( "Throw an exception and test failed! " );          }This code; (2). The Code of the last job is also found to be incorrect. The last one of the three operators is the divisor, but it is not written:

If (fh2 = '/') // The first is except {If (fh3 = '+') {If (fh4 = '+ ') {If (B = 0) {Throw new exception ("the divisor cannot be 0! ");} Answer = A/B + C + D;} If (fh4 = '-') {If (B = 0) {Throw new exception ("the divisor cannot be 0! ");} Answer = A/B + c-d;} If (fh4 = '*') {If (B = 0) {Throw new exception ("the divisor cannot be 0! ");} Answer = A/B + C * D;} If (fh4 = '/') {If (B = 0) {Throw new exception ("the divisor cannot be 0! ");} If (D = 0) {Throw new exception (" the divisor cannot be 0! ");} Answer = A/B + C/d;} If (fh3 = '-') {If (fh4 = '+ ') {If (B = 0) {Throw new exception ("the divisor cannot be 0! ");} Answer = A/B-C + D;} If (fh4 = '-') {If (B = 0) {Throw new exception ("the divisor cannot be 0! ");} Answer = a/B-c-d;} If (fh4 = '*') {If (B = 0) {Throw new exception ("the divisor cannot be 0! ");} Answer = a/B-c * D;} If (fh4 = '/') {If (B = 0) {Throw new exception ("the divisor cannot be 0! ");} If (D = 0) {Throw new exception (" the divisor cannot be 0! ");} Answer = A/B-C/d;} If (fh3 = '*') {If (fh4 = '+ ') {If (B = 0) {Throw new exception ("the divisor cannot be 0! ");} Answer = A/B * C + D;} If (fh4 = '-') {If (B = 0) {Throw new exception ("the divisor cannot be 0! ");} Answer = A/B * c-d;} If (fh4 = '*') {If (B = 0) {Throw new exception ("the divisor cannot be 0! ");} Answer = A/B * C * D;} If (fh4 = '/') {If (B = 0) {Throw new exception ("the divisor cannot be 0! ");} If (D = 0) {Throw new exception (" the divisor cannot be 0! ");} Answer = A/B * C/d;} If (fh3 = '/') {If (fh4 = '+ ') {If (B = 0) {Throw new exception ("the divisor cannot be 0! ");} If (C = 0) {Throw new exception (" the divisor cannot be 0! ");} Answer = A/B/C + D;} If (fh4 = '-') {If (B = 0) {Throw new exception ("the divisor cannot be 0! ");} If (C = 0) {Throw new exception (" the divisor cannot be 0! ");} Answer = A/B/C-D;} If (fh4 = '*') {If (B = 0) {Throw new exception ("the divisor cannot be 0! ");} If (C = 0) {Throw new exception (" the divisor cannot be 0! ");} Answer = A/B/C * D;} If (fh4 = '/') {If (B = 0) {Throw new exception ("the divisor cannot be 0! ");} If (C = 0) {Throw new exception (" the divisor cannot be 0! ");} If (D = 0) {Throw new exception (" the divisor cannot be 0! ") ;}Answer = A/B/C/D ;}} return answer ;}

(3) Here, we also add the exact decimal point of the answer:

static double answer=0.0d;

public static double Onefhnum(int a,int b,int e)throws Exception{// Method of an operator

public static double Twofhnum(int a,int b,int c,int e,int h)throws Exception{// Two operators

public static double Threefhnum(int a,int b,int c,int d,int e,int h,int f)throws Exception{// Methods of the three operators

(4). Due to time, the following code is added:int precision = 0;

         if  (NUM_MAX_OPERATOR == precision) {              // Here I can process strings with a maximum of three operators :)          }  else  if  (NUM_SCALE == precision) {              // Here I can process a string with a value range of-100 to 100 :)          }  else  if  (NUM_PRECISION == precision) {              // Here I can handle strings whose precision is the first digit after the decimal point :)          }After this code, you do not know how to add or process information in parentheses.

Four arithmetic testing and encapsulation (improved) 5.2 5.3