OO for Java - Basic

This OO test focuses on OO and OO design. It may contain small elements of Java to make things more concrete, but it's not the purpose of testing Java knowledge here. For example, trick Java specific overriding questions are part of the Java SE exams. These objectives and questions may contain general programming elements when it's difficult to dissociate non-OO from OO topics.

The OO basic test is bound to the Java SE basic test. For example, we do not require the knowledge of advanced polymorphism for Java SE basic, implies that we do not require this knowledge for 'OO basic'. We must enforce this because both exams are part of the same yellow belt that we want to be easy to succeed. If you are new to OO, we advice to prepare both 'OO basic' and 'Java SE basic' exams together. If you already know OO from another language, this should not be necessary, just have a minimal knowledge of the Java notation.

	Released	Beta	Frozen
Object and Class 2 questions Prove a basic knowledge of object manipulation. Differentiate class and object instance of a class, a class may have multiple instances. Understand the reference mechanism, ascertain the difference between an object and its reference. Identify impact on: comparing objects (`==` vs. `.equals()`) assignments passing methods arguments Manipulate state of objects (set of object's attributes), predict object state after manipulations	42	170	117	Add a question Beta questions
Lifecycle 1 question Be familiar with the object lifecycle Identify lifecycle states : construction, existence - reachable or not using references, destruction Given code, predict what happens with special focus to initialization Determine object initialization and the role played by the constructor	14	7	60	Add a question Beta questions
Association 2 questions Build object associations Understand the association concept : Association defines a relationship between classes of objects which allows one object instance to cause another to perform an action on its behalf Given code, determine association directionality and multiplicity. Write Java code that implements an association unique with an object reference multiple with a collection or array of references	10	0	40	Add a question Beta questions
Encapsulation 3 questions Demonstrate knowledge of encapsulation Understand the main meaning of encapsulation: Separation of concerns and information hiding. The process of enclosing programming elements inside larger, more abstract entities. Define what an accessor is and the derived vocabulary: Accessor Mutator Setter Getter Demonstrate basic knowledge of instance variable and methods manipulation Be familiar with terminology, juggle with attribute's synonyms: fields, instance variables, properties Stress a difference between the direct and indirect (method) access to the attributes Given code, predict assignment result for instance variables, method arguments and local variables Know that object references are passed by value to methods and that the referenced object is not copied: When an object is passed to a (Java) method, the code inside the method modifies the states (the attributes) of the object. Back from the method execution, in the caller code, the object state is not restored and remains affected.	24	2	98	Add a question Beta questions
Inheritance 3 questions Understand the basic notions of inheritance Given a class hierarchy, identify parents and children Write code that performs up and down-casting. The basic level does not cover polymorphism.	46	127	121	Add a question Beta questions
UML - Basic Class Diagram 2 questions identify the basic parts of the UML representation for a class: Class name Attribute section Method section It does not include: Relationships like representing association and inheritance Access modifiers Stereotypes Assume UML version 2.0 if not stated otherwise.	3	4	57	Add a question Beta questions