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High Cohesion












[Time: 4 mins]


  • Stuff that goes together, stays together
  • Easy to discover relevant code
  • Levels of cohesion
    • packages
    • classes
    • methods 
 
So in very simple words, cohesion is keeping related stuff together so we can find what we want without too much difficulty. 
 

 





















Example 1

public class Student {

    //cohesive methods

    public void registerForCourse() {}

    public void deregisterFromCourse() {}

    viewTranscripts() {}

    //methods below are not in synch with the responsibilities of the Student class

    //hence cohesion is broken

    submit grades() {}

    submitCourseSchedule() {}

 





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Note: This post was originally posted on my blog at http://www.adaptivelearningonline.net

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