摘要：In object oriented paradigm, cohesion of a class refers to the degree to which members of the class are interrelated. Metrics have been defined to measure cohesiveness of a class both at design and source code levels. In comparison to source code level class cohesion metrics, only a few design level class cohesion metrics have been proposed. Design level class cohesion metrics are based on the assumption that if all the methods of a class have access to similar para-meter types then they all process closely related information. A class with a large number of parameter types common in its methods is more cohesive than a class with less number of parameter types common in its methods. In this paper, we review the design level class cohesion metrics with a special focus on metrics which use similarity of parameter types of methods of a class as the basis of its cohesiveness. Basically three metrics fall in this category: Cohesion among Methods of a Class (CAMC), Normalized Hamming Distance (NHD), and Scaled NHD (SNHD). Keeping in mind the anomalies in the definitions of the existing metrics, a variant of the existing metrics is introduced. It is named NHD Modified (NHDM). An automated metric collection tool is used to collect the metric data from an open source software program. The metric data is then subjected to statistical analysis.

摘要：Introduction‘Life always makes us black and blue,but those painful things will make us stronger until we came through.’Hemingway once ***,is this true?Perhaps we do recover from pain but sometimes it could kill *** for a typical high school student in an elite school in China,I feel anxiety *** pressure from classmates,teachers,parents and even from friends could easily turn something small into a serious *** kind of issue will finally lead to negative emotions that strongly affect students’academic behaviors and attitudes toward *** fact,this situation is being more and more prevalent among today’s Chinese high school *** of students’anxiety Anxiety is defined as a subjective sense of fear,distress,or worry that may exhibit both physical sensations(e.g.,headaches or nausea)and emotional symptoms(e.g.,fear or nervousness)(American Psychiatric Association[APA],2000).Studies have shown that when students feel nervous,afraid,panic,it could be the symptoms of ***,these students often feel worried,tired,dizzy and easier to have bad ***,anxiety could have significant influence on students’behaviors on their academic performance and productivity.