上游充鱼大姿 SJTU School Of Software 2009-2-3 Why? 必 The current development methods of software are: Depend on people's intelligence Specification is informal or even chaos > Software development tools are not self- contained > Software development process is elective and without standards on detail 在当前的软件开发方法学指导下开发软件，软件 测试仍是保证软件质量和可靠性的重要手段。 软件学院
SJTU School Of Software 2009-2-3 软件学院 Why? The current development methods of software are: ¾ Depend on people’s intelligence ¾ Specification is informal or even chaos ¾ Software development tools are not selfcontained ¾ Software development process is elective and without standards on detail 在当前的软件开发方法学指导下开发软件，软件 测试仍是保证软件质量和可靠性的重要手段
上游充鱼大 SJTU School Of Software 2009-2-3 Cost/benefit Testing takes more than 50%of the total cost of software development More for critical software Software quality will become the dominant success criterion 软件学院
SJTU School Of Software 2009-2-3 软件学院 Cost/benefit • Testing takes more than 50% of the total cost of software development – More for critical software • Software quality will become the dominant success criterion
上浒充通大 SJTU School Of Software 2009-2-3 The understanding of software test Exhausted test is impossible to realized. > Software test can not ensure to uncover all errors of a software. Software test can not instead of other quality insurance methods 软件测试：巨大的效益和艰苦的工作并存 软件学院
SJTU School Of Software 2009-2-3 软件学院 The understanding of software test 软件测试：巨大的效益和艰苦的工作并存 ¾ Exhausted test is impossible to realized. ¾ Software test can not ensure to uncover all errors of a software. ¾ Software test can not instead of other quality insurance methods
上游充道大粤 SJTU School Of Software 2009-2-3 Some examples 1 Exception if(state =0) { } state ==i 1) {..}; 软件学院
SJTU School Of Software 2009-2-3 软件学院 Some examples 1 Exception if(state = = 0) { … } if(state = = 1) { … } ；
上游充鱼大 SJTU School Of Software 2009-2-3 2 Data overflow Int count(int &a,int month_num) int month_income 0,i; for(i=0;i<month_num;i++) month_income+=a[i]; return month_income; } 11 000<a[i<10000 软件学院
SJTU School Of Software 2009-2-3 软件学院 2 Data overflow Int count( int &a, int month_num) { int month_income = 0, i; for( i = 0; i< month_num; i++) month_income+=a[i]; return month_income; } //1000<a[i]<10000