Java Chapter 04 - Writing Classes: part 1

Java Chapter 04 - Writing Classes: part 1

• 1.
  Chapter 4 Writing Classes –Part 1 Java Software Solutions Foundations of Program Design 9th Edition John Lewis William Loftus
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  Key Concept • Theheart of object-oriented programming is defining classes that represent objects with well-defined state and behavior.
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  Key Concept • Thescope of a variable, which determines where it can be referenced, depends on where it is declared.
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  Key Concept • AUML class diagram helps us visualize the contents of and relationships among the classes of a program.
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  Key Concept An objectshould be encapsulated, guarding its data from inappropriate access.
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  Key Concept Instance variablesshould be declared with private visibility to promote encapsulation.
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  Key Concept • Mostobjects contain accessor and mutator methods to allow the client to manage data in a controlled manner.
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  Key Concept The valuereturned from a method must be consistent with the return type in the method header.
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  Key Concept When amethod is called, the actual parameters are copied into the formal parameters.
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  Key Concept A variabledeclared in a method is local to that method and cannot be used outside of it.
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  Key Concept A constructorcannot have any return type, even void.
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  Writing Classes • We've beenusing predefined classes from the Java API. Now we will learn to write our own classes. • Chapter 4 focuses on: • class definitions • instance data • encapsulation and Java modifiers • method declaration and parameter passing • constructors