Experiment Three white Box test

Experimental purpose

(1) Learn white box test method

(2) Mastering the logic covering methods of statement coverage, conditional coverage, branch coverage, etc.

(3) Mastering the use of Java Code Analysis tools

Experimental content

1. Computes the greatest common divisor of integer x and integer y. (not allowed in the way the classroom is used)

? Use classes and methods (write a method for greatest common divisor), and name them according to the specification.

? in the main mode, get the two integers entered by the user, call the previously written method, and output their greatest common divisor.

? use FindBugs to find out if a bug exists in the program.

 Packagecn.lq.com;ImportJava.io.*;ImportJava.util.*;classDemo { Public Static voidMain (String args[])throwsException {Scanner cin=NewScanner (system.in); System.out.println ("Please enter the first number:"); intA =Cin.nextint (); System.out.println ("\ n Please enter a second number:"); intb =Cin.nextint (); intc =gcd (A, b); System.out.println ("\ n Greatest Common divisor:" +c); }     Public Static intgcdintAintb) { while(true) {            if((a = a% b) = = 0)                returnb; if((b = b% a) = = 0)                returnA; }    }    }

No syntax errors

2, the application of logic coverage

? write Java code (implemented using classes and methods) according to the program flowchart given

? Write a test case for a statement overlay, a branch overlay, and the path it covers, test with JUnit

 Packagecn.lq.com;ImportJava.util.Scanner; Public classDemo {/** * @paramargs*/ Public Static  voidTfloatXfloaty) {System.out.print ("The path passed is a");if(x<4| | Y>0) {System.out.print ("B");if(y>1) {System.out.println (C); y=y+1; System.out.println ("X=" +x); System.out.println ("Y=" +y);}Else{System.out.println ("D"); System.out.println ("End judgment"); System.out.println ("X=" +x); System.out.println ("Y=" +y);}}Else{System.out.print (E);if(x>=5) {System.out.println ("F"); x=x-y; System.out.println ("X=" +x); System.out.println ("Y=" +y);}Else{System.out.println ("G"); x=x+y; System.out.println ("X=" +x); System.out.println ("Y=" +y); }}}

Test class

 package   cn.lq.com;  import  static  org.junit.assert.*;  import   Org.junit.Test;  public  class   Demotest {@Test  public  void   Test () { float  x = 2; float  y = 1 "test two numbers for x=" +x+ "y=" +y+ ""  

Statement overrides

Test Cases	Overwrite use cases	Results
< Span style= "font-family: ' Courier New ';" >x=4 y=0	aeg	x=4 y=0
< Span style= "font-family: ' Courier New ';" >x=5 y=0	aef	x=5 y=0
X=2 y=2	Adc	X=2 Y=3

Branch Overrides

< Span style= "font-family: ' Courier New ';" > test case	overwrite use case	result
< Span style= "font-family: ' Courier New ';" >x=4 y=0	aeg	x=4 y=0
< Span style= "font-family: ' Courier New ';" >x=5 y=0	aef	x=5 y=0
< Span style= "font-family: ' Courier New ';" >x=2 y=2	ADC	x=2 y=3
x=2 Y=1	Abd	x=2 Y=1

We test the statements covered by the

Experiment Three white Box test