title: referencing class variable to a local variable
body: <p>why do some people make a new reference in method to a field variable?</p>
  
  <pre><code>public class Foo {
      int mFoo[] = {1, 2, 3};
  
      void method() {
          int foo[] = mFoo; // WHY not just use mFoo?
  
          print(foo[0]); // WHY not just use mFoo?
      }
  }
  </code></pre>