title: Change parameter of method
body: <p>Say I have a following function in java, may be not good example but just came in mind ;)</p>
  
  <pre><code>public StudentEntity updateStudent(StudentEntity studentEntity)
  {
      studentEntity.setName(...);
      studentEntity.setAddress(...);
      return studentEntity;
  }
  </code></pre>
  
  <p>Is above approach valid? </p>
  
  <p>Can we store a studentEntity in separate variable and update and return it.
  For example</p>
  
  <pre><code>public StudentEntity updateStudent(StudentEntity studentEntity)
  {
      StudentEntity _studentEntity = studentEntity;
      _studentEntity.setName(...);
      _studentEntity.setAddress(...);
      return _studentEntity;
  }
  </code></pre>
  
  <p>Is this correct ? How mutator methods should be? Please make me correct if wrong!</p>