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--- qtr_2_study_guide [2019/12/03 14:48] – cthiel
+++ qtr_2_study_guide [2019/12/03 14:51] – cthiel
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 Things to watch out for:
-  - not initializing a field ( fields are private, to encapsulate)
+  - Constructors should initialize the class's  fields  (fields are ''private'', to encapsulate)
-  - accidentally making a local variable instead of initializing a variable
+  - When initialzing fields in a constructor, **Do not** mention its type- this accidentally makes a local variable instead of initializing the classes field that has the same name.
-  - remember to make methods public, and don't forget to use () for the parameter list, even if there are none
+  - Remember to make fields ''private'' and methods ''public'',
-  - local variables are never public nor private
+  - Remember local variables are **never** public nor private
-  - dangling else statements (p 148)
+  - Remember method names should use () for the parameter list, even if there are no parameters
-  - forgetting to have a method return something of the correct type
+  - Watch for dangling else statements (p 148) - without brackets, the last ''else'' belongs to the previous ''if''
-  - not to add a System.out.print were no printing is requested (This can be a 1 or 2 point 'Extraneous code that causes side effect' penalty on the AP Exam)
+  - **Do not** add a ''System.out.print'' when no printing is requested (This can be a 1 or 2 point **Extraneous code that causes side effect** penalty on the AP Exam)
-  - using local variables that you don't declare ( also a AP scoring penalty)
+  - **Do not** use local variables before first declaring them ( also a AP scoring penalty).
-  - changing a value referenced by parameter or destroying data in a parameter (also a scoring penalty)
+  - Variables are declared ONLY ONCE, not every time.
-  - return statement on a constructor, or a method that isn't supposed to return something (a 'void' method).  This too has a AP scoring penalty)
+  - **Do not** assign a value to a parameter inside a method unless you are asked to (also a AP scoring penalty called **Destruction of data**)
+  - **Never** use ''return'' in a constructor
+  - Remember to ''return'' something of the same type as a method's header.
+  - **Do not** ''return'' something when writing a ''void'' method ( a method that isn't supposed to return something (This too has a AP scoring penalty)
 Finally, please remember to get a good night's rest and a healthy breakfast!