IB Computer Science HL · Year 2 · Lesson 13
Encapsulation and information hiding
Object-oriented programming models a problem through classes and objects, with clear responsibilities and controlled access to state.
Paper 250 minutesB3.1.5
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Today’s targets
What you need to be able to do
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- Explain + applyAnd apply the concepts of encapsulation and information hiding in OOP
B3.1.5
Paper 2 lensMatch the depth of every response to the command term. Previously learned content can move quickly, but retrieval must still be accurate.
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Retrieve
Rapid Recall Deck
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Say the answer aloud before flipping. Mark secure knowledge quickly and spend time on the gaps.
- What is encapsulation?: The bundling of an object's data and the methods that operate on that data within a class.
- What is information hiding?: Restricting direct access to implementation details so the object's internal state can only be changed through controlled interfaces.
- What is the purpose of a private member?: It prevents unrestricted access from outside the class and helps protect the object's internal state.
- What is the purpose of a public member?: It forms part of the interface that other code is allowed to access.
- Why does limiting access to class members matter?: It helps maintain the integrity and security of object state by preventing invalid or unintended changes.
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B3.1.5 · Learn
Core knowledge and application
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B3.1.5Explain + apply
And apply the concepts of encapsulation and information hiding in OOP
Object-oriented programming models a problem through classes and objects, with clear responsibilities and controlled access to state.
Exam moveGive the mechanism or relationship and make the reasons/causes explicit.
Required detail 1The principles of encapsulation and information hiding
Required detail 2Apply access modifiers such as private and public
Required detail 3Controlling access to class members
Required detail 4The importance of limiting access to maintain the integrity and security of an object's state
Assessment boundaryPaper 2
Explain it without notes
Explain + apply: And apply the concepts of encapsulation and information hiding in OOP in the context of a library-management application.
- The principles of encapsulation and information hiding
- Apply access modifiers such as private and public
- Controlling access to class members
- The importance of limiting access to maintain the integrity and security of an object's state
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Apply
Transfer to a new scenario
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ScenarioA library-management application needs a design or technical decision related to today’s topic. Explain what matters and why.
- The principles of encapsulation and information hiding
- Apply access modifiers such as private and public
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Exam lens
Paper 2 practice
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Build the response before checking notesUse precise terminology and match the required depth.
- Explain + apply: And apply the concepts of encapsulation and information hiding in OOP in the context of a library-management application.
Self-checkAnswer the exact command term. For explain, include mechanism/reason; for compare, pair criteria; for discuss/evaluate/justify, build supported reasoning and a conclusion.
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Homework
Finish the learning cycle
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IA — main task
Continue Criterion D development. Keep code readable, record meaningful implementation decisions, and maintain testing/evidence notes as you work.
Syllabus — short
Complete one targeted Paper 2/Paper 1 retrieval task from today’s lesson.
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End of Lesson 13.