Java Design Patterns MCQ Questions with Answers – Page 2 (Latest 2026)

Q51. Which statement about Chain of Responsibility is most accurate?

A. Pass requests along a chain. B. An observer. C. Single handler always. D. A command.

Select an answer to check.

Answer: Pass requests along a chain.

Here, Pass requests along a chain. is the right choice. Decouples sender and handler. It aligns directly with what the question asks about which statement about chain of responsibility is most. Competing choices sound plausible, but they miss the key condition.

Q52. How is Chain of Responsibility best characterized?

A. An observer. B. Pass requests along a chain. C. Single handler always. D. A command.

Select an answer to check.

Answer: Pass requests along a chain.

In this case, Pass requests along a chain. is correct. Decouples sender and handler. It aligns directly with what the question asks about how is chain of responsibility best characterized. Competing choices sound plausible, but they miss the key condition.

Q53. Which option best describes Command in Java?

A. A pure mediator. B. A pure observer. C. Encapsulates a request. D. A pure visitor.

Select an answer to check.

Answer: Encapsulates a request.

The best option here is Encapsulates a request.. Enables undo, queues. It aligns directly with what the question asks about which option best describes command in java. Competing choices sound plausible, but they miss the key condition.

Q54. What is the primary purpose of Command?

A. A pure visitor. B. Encapsulates a request. C. A pure mediator. D. A pure observer.

Select an answer to check.

Answer: Encapsulates a request.

For this question, Encapsulates a request. is correct. Enables undo, queues. It aligns directly with what the question asks about what is the primary purpose of command. Competing choices sound plausible, but they miss the key condition.

Q55. Which statement about Command is most accurate?

A. A pure observer. B. Encapsulates a request. C. A pure mediator. D. A pure visitor.

Select an answer to check.

Answer: Encapsulates a request.

Encapsulates a request. is the correct answer here. Enables undo, queues. It aligns directly with what the question asks about which statement about command is most accurate. Competing choices sound plausible, but they miss the key condition.

Q56. How is Command best characterized?

A. A pure visitor. B. A pure observer. C. Encapsulates a request. D. A pure mediator.

Select an answer to check.

Answer: Encapsulates a request.

Here, Encapsulates a request. is the right choice. Enables undo, queues. This matches the core idea being tested around how is command best characterized. Competing choices sound plausible, but they miss the key condition.

Q57. Which option best describes Iterator in Java?

A. A pure mediator. B. Sequential access without exposing structure. C. A pure visitor. D. A pure observer.

Select an answer to check.

Answer: Sequential access without exposing structure.

In this case, Sequential access without exposing structure. is correct. Java has Iterator interface. This matches the core idea being tested around which option best describes iterator in java. Competing choices sound plausible, but they miss the key condition.

Q58. What is the primary purpose of Iterator?

A. Sequential access without exposing structure. B. A pure observer. C. A pure mediator. D. A pure visitor.

Select an answer to check.

Answer: Sequential access without exposing structure.

The best option here is Sequential access without exposing structure.. Java has Iterator interface. This matches the core idea being tested around what is the primary purpose of iterator. Competing choices sound plausible, but they miss the key condition.

Q59. Which statement about Iterator is most accurate?

A. A pure visitor. B. Sequential access without exposing structure. C. A pure mediator. D. A pure observer.

Select an answer to check.

Answer: Sequential access without exposing structure.

For this question, Sequential access without exposing structure. is correct. Java has Iterator interface. This matches the core idea being tested around which statement about iterator is most accurate. Competing choices sound plausible, but they miss the key condition.

Q60. How is Iterator best characterized?

A. A pure visitor. B. A pure observer. C. A pure mediator. D. Sequential access without exposing structure.

Select an answer to check.

Answer: Sequential access without exposing structure.

Sequential access without exposing structure. is the correct answer here. Java has Iterator interface. This matches the core idea being tested around how is iterator best characterized. Competing choices sound plausible, but they miss the key condition.

Q61. Which option best describes Mediator in Java?

A. A pure command. B. A pure observer. C. Centralizes communication among colleagues. D. A pure visitor.

Select an answer to check.

Answer: Centralizes communication among colleagues.

Here, Centralizes communication among colleagues. is the right choice. Reduces coupling. That is exactly the concept behind which option best describes mediator in java in this context. Competing choices sound plausible, but they miss the key condition.

Q62. What is the primary purpose of Mediator?

A. Centralizes communication among colleagues. B. A pure observer. C. A pure command. D. A pure visitor.

Select an answer to check.

Answer: Centralizes communication among colleagues.

In this case, Centralizes communication among colleagues. is correct. Reduces coupling. That is exactly the concept behind what is the primary purpose of mediator in this context. Competing choices sound plausible, but they miss the key condition.

Q63. Which statement about Mediator is most accurate?

A. A pure command. B. Centralizes communication among colleagues. C. A pure observer. D. A pure visitor.

Select an answer to check.

Answer: Centralizes communication among colleagues.

The best option here is Centralizes communication among colleagues.. Reduces coupling. That is exactly the concept behind which statement about mediator is most accurate in this context. Competing choices sound plausible, but they miss the key condition.

Q64. How is Mediator best characterized?

A. A pure command. B. A pure visitor. C. A pure observer. D. Centralizes communication among colleagues.

Select an answer to check.

Answer: Centralizes communication among colleagues.

For this question, Centralizes communication among colleagues. is correct. Reduces coupling. That is exactly the concept behind how is mediator best characterized in this context. Competing choices sound plausible, but they miss the key condition.

Q65. Which option best describes Memento in Java?

A. A pure command. B. A pure visitor. C. A pure observer. D. Capture/restore state.

Select an answer to check.

Answer: Capture/restore state.

Capture/restore state. is the correct answer here. Implements undo/redo. That is exactly the concept behind which option best describes memento in java in this context. Competing choices sound plausible, but they miss the key condition.

Q66. What is the primary purpose of Memento?

A. A pure visitor. B. A pure command. C. Capture/restore state. D. A pure observer.

Select an answer to check.

Answer: Capture/restore state.

Here, Capture/restore state. is the right choice. Implements undo/redo. It fits the requirement in the prompt about what is the primary purpose of memento. Competing choices sound plausible, but they miss the key condition.

Q67. Which statement about Memento is most accurate?

A. A pure command. B. Capture/restore state. C. A pure visitor. D. A pure observer.

Select an answer to check.

Answer: Capture/restore state.

In this case, Capture/restore state. is correct. Implements undo/redo. It fits the requirement in the prompt about which statement about memento is most accurate. Competing choices sound plausible, but they miss the key condition.

Q68. How is Memento best characterized?

A. A pure visitor. B. Capture/restore state. C. A pure command. D. A pure observer.

Select an answer to check.

Answer: Capture/restore state.

The best option here is Capture/restore state.. Implements undo/redo. It fits the requirement in the prompt about how is memento best characterized. Competing choices sound plausible, but they miss the key condition.

Q69. Which option best describes Observer in Java?

A. Visitor pattern. B. Mediator pattern. C. Command pattern. D. Notify many on state change.

Select an answer to check.

Answer: Notify many on state change.

For this question, Notify many on state change. is correct. PropertyChangeSupport in Java. It fits the requirement in the prompt about which option best describes observer in java. Competing choices sound plausible, but they miss the key condition.

Q70. What is the primary purpose of Observer?

A. Notify many on state change. B. Command pattern. C. Visitor pattern. D. Mediator pattern.

Select an answer to check.

Answer: Notify many on state change.

Notify many on state change. is the correct answer here. PropertyChangeSupport in Java. It fits the requirement in the prompt about what is the primary purpose of observer. Competing choices sound plausible, but they miss the key condition.

Q71. Which statement about Observer is most accurate?

A. Mediator pattern. B. Notify many on state change. C. Command pattern. D. Visitor pattern.

Select an answer to check.

Answer: Notify many on state change.

Here, Notify many on state change. is the right choice. PropertyChangeSupport in Java. This is the most accurate statement for which statement about observer is most accurate. Competing choices sound plausible, but they miss the key condition.

Q72. How is Observer best characterized?

A. Notify many on state change. B. Command pattern. C. Mediator pattern. D. Visitor pattern.

Select an answer to check.

Answer: Notify many on state change.

In this case, Notify many on state change. is correct. PropertyChangeSupport in Java. This is the most accurate statement for how is observer best characterized. Competing choices sound plausible, but they miss the key condition.

Q73. Which option best describes State in Java?

A. Visitor pattern. B. Strategy pattern. C. Iterator pattern. D. Behavior changes with internal state.

Select an answer to check.

Answer: Behavior changes with internal state.

The best option here is Behavior changes with internal state.. Encapsulate state. This is the most accurate statement for which option best describes state in java. Competing choices sound plausible, but they miss the key condition.

Q74. What is the primary purpose of State?

A. Iterator pattern. B. Visitor pattern. C. Strategy pattern. D. Behavior changes with internal state.

Select an answer to check.

Answer: Behavior changes with internal state.

For this question, Behavior changes with internal state. is correct. Encapsulate state. This is the most accurate statement for what is the primary purpose of state. Competing choices sound plausible, but they miss the key condition.

Q75. Which statement about State is most accurate?

A. Visitor pattern. B. Strategy pattern. C. Behavior changes with internal state. D. Iterator pattern.

Select an answer to check.

Answer: Behavior changes with internal state.

Behavior changes with internal state. is the correct answer here. Encapsulate state. This is the most accurate statement for which statement about state is most accurate. Competing choices sound plausible, but they miss the key condition.

Q76. How is State best characterized?

A. Iterator pattern. B. Visitor pattern. C. Strategy pattern. D. Behavior changes with internal state.

Select an answer to check.

Answer: Behavior changes with internal state.

Here, Behavior changes with internal state. is the right choice. Encapsulate state. It aligns directly with what the question asks about how is state best characterized. The remaining choices fail because they don’t satisfy the full definition.

Q77. Which option best describes Strategy in Java?

A. Bridge pattern. B. Family of interchangeable algorithms. C. State pattern. D. Visitor pattern.

Select an answer to check.

Answer: Family of interchangeable algorithms.

In this case, Family of interchangeable algorithms. is correct. Inject behavior. It aligns directly with what the question asks about which option best describes strategy in java. The remaining choices fail because they don’t satisfy the full definition.

Q78. What is the primary purpose of Strategy?

A. State pattern. B. Bridge pattern. C. Family of interchangeable algorithms. D. Visitor pattern.

Select an answer to check.

Answer: Family of interchangeable algorithms.

The best option here is Family of interchangeable algorithms.. Inject behavior. It aligns directly with what the question asks about what is the primary purpose of strategy. The remaining choices fail because they don’t satisfy the full definition.

Q79. Which statement about Strategy is most accurate?

A. Bridge pattern. B. Family of interchangeable algorithms. C. Visitor pattern. D. State pattern.

Select an answer to check.

Answer: Family of interchangeable algorithms.

For this question, Family of interchangeable algorithms. is correct. Inject behavior. It aligns directly with what the question asks about which statement about strategy is most accurate. The remaining choices fail because they don’t satisfy the full definition.

Q80. How is Strategy best characterized?

A. Family of interchangeable algorithms. B. Visitor pattern. C. Bridge pattern. D. State pattern.

Select an answer to check.

Answer: Family of interchangeable algorithms.

Family of interchangeable algorithms. is the correct answer here. Inject behavior. It aligns directly with what the question asks about how is strategy best characterized. The remaining choices fail because they don’t satisfy the full definition.

Q81. Which option best describes Template Method in Java?

A. Strategy pattern. B. Visitor pattern. C. Algorithm skeleton, steps in subclass. D. Command pattern.

Select an answer to check.

Answer: Algorithm skeleton, steps in subclass.

Here, Algorithm skeleton, steps in subclass. is the right choice. Inheritance-based. This matches the core idea being tested around which option best describes template method in java. The remaining choices fail because they don’t satisfy the full definition.

Q82. What is the primary purpose of Template Method?

A. Strategy pattern. B. Visitor pattern. C. Algorithm skeleton, steps in subclass. D. Command pattern.

Select an answer to check.

Answer: Algorithm skeleton, steps in subclass.

In this case, Algorithm skeleton, steps in subclass. is correct. Inheritance-based. This matches the core idea being tested around what is the primary purpose of template method. The remaining choices fail because they don’t satisfy the full definition.

Q83. Which statement about Template Method is most accurate?

A. Command pattern. B. Strategy pattern. C. Algorithm skeleton, steps in subclass. D. Visitor pattern.

Select an answer to check.

Answer: Algorithm skeleton, steps in subclass.

The best option here is Algorithm skeleton, steps in subclass.. Inheritance-based. This matches the core idea being tested around which statement about template method is most accurate. The remaining choices fail because they don’t satisfy the full definition.

Q84. How is Template Method best characterized?

A. Strategy pattern. B. Visitor pattern. C. Command pattern. D. Algorithm skeleton, steps in subclass.

Select an answer to check.

Answer: Algorithm skeleton, steps in subclass.

For this question, Algorithm skeleton, steps in subclass. is correct. Inheritance-based. This matches the core idea being tested around how is template method best characterized. The remaining choices fail because they don’t satisfy the full definition.

Q85. Which option best describes Visitor in Java?

A. Add operations without modifying classes. B. Iterator pattern. C. Observer pattern. D. Command pattern.

Select an answer to check.

Answer: Add operations without modifying classes.

Add operations without modifying classes. is the correct answer here. Useful for ASTs. This matches the core idea being tested around which option best describes visitor in java. The remaining choices fail because they don’t satisfy the full definition.

Q86. What is the primary purpose of Visitor?

A. Command pattern. B. Iterator pattern. C. Add operations without modifying classes. D. Observer pattern.

Select an answer to check.

Answer: Add operations without modifying classes.

Here, Add operations without modifying classes. is the right choice. Useful for ASTs. That is exactly the concept behind what is the primary purpose of visitor in this context. The remaining choices fail because they don’t satisfy the full definition.

Q87. Which statement about Visitor is most accurate?

A. Add operations without modifying classes. B. Observer pattern. C. Iterator pattern. D. Command pattern.

Select an answer to check.

Answer: Add operations without modifying classes.

In this case, Add operations without modifying classes. is correct. Useful for ASTs. That is exactly the concept behind which statement about visitor is most accurate in this context. The remaining choices fail because they don’t satisfy the full definition.

Q88. How is Visitor best characterized?

A. Iterator pattern. B. Observer pattern. C. Command pattern. D. Add operations without modifying classes.

Select an answer to check.

Answer: Add operations without modifying classes.

The best option here is Add operations without modifying classes.. Useful for ASTs. That is exactly the concept behind how is visitor best characterized in this context. The remaining choices fail because they don’t satisfy the full definition.

Q89. Which option best describes Repository in Java?

A. Abstracts data access. B. Pure singleton. C. Pure factory. D. Pure observer.

Select an answer to check.

Answer: Abstracts data access.

For this question, Abstracts data access. is correct. DDD-friendly. That is exactly the concept behind which option best describes repository in java in this context. The remaining choices fail because they don’t satisfy the full definition.

Q90. What is the primary purpose of Repository?

A. Pure factory. B. Abstracts data access. C. Pure observer. D. Pure singleton.

Select an answer to check.

Answer: Abstracts data access.

Abstracts data access. is the correct answer here. DDD-friendly. That is exactly the concept behind what is the primary purpose of repository in this context. The remaining choices fail because they don’t satisfy the full definition.

Q91. Which statement about Repository is most accurate?

A. Abstracts data access. B. Pure observer. C. Pure singleton. D. Pure factory.

Select an answer to check.

Answer: Abstracts data access.

Here, Abstracts data access. is the right choice. DDD-friendly. It fits the requirement in the prompt about which statement about repository is most accurate. The remaining choices fail because they don’t satisfy the full definition.

Q92. How is Repository best characterized?

A. Pure factory. B. Abstracts data access. C. Pure observer. D. Pure singleton.

Select an answer to check.

Answer: Abstracts data access.

In this case, Abstracts data access. is correct. DDD-friendly. It fits the requirement in the prompt about how is repository best characterized. The remaining choices fail because they don’t satisfy the full definition.

Q93. Which option best describes Service Locator in Java?

A. A pure repository. B. DI is the only alternative. C. Central registry of services (anti-pattern). D. A pure observer.

Select an answer to check.

Answer: Central registry of services (anti-pattern).

The best option here is Central registry of services (anti-pattern).. Hides dependencies; prefer DI. It fits the requirement in the prompt about which option best describes service locator in java. The remaining choices fail because they don’t satisfy the full definition.

Q94. What is the primary purpose of Service Locator?

A. DI is the only alternative. B. A pure observer. C. A pure repository. D. Central registry of services (anti-pattern).

Select an answer to check.

Answer: Central registry of services (anti-pattern).

For this question, Central registry of services (anti-pattern). is correct. Hides dependencies; prefer DI. It fits the requirement in the prompt about what is the primary purpose of service locator. The remaining choices fail because they don’t satisfy the full definition.

Q95. Which statement about Service Locator is most accurate?

A. A pure repository. B. Central registry of services (anti-pattern). C. A pure observer. D. DI is the only alternative.

Select an answer to check.

Answer: Central registry of services (anti-pattern).

Central registry of services (anti-pattern). is the correct answer here. Hides dependencies; prefer DI. It fits the requirement in the prompt about which statement about service locator is most accurate. The remaining choices fail because they don’t satisfy the full definition.

Q96. How is Service Locator best characterized?

A. A pure observer. B. Central registry of services (anti-pattern). C. DI is the only alternative. D. A pure repository.

Select an answer to check.

Answer: Central registry of services (anti-pattern).

Here, Central registry of services (anti-pattern). is the right choice. Hides dependencies; prefer DI. This is the most accurate statement for how is service locator best characterized. The remaining choices fail because they don’t satisfy the full definition.

Q97. Which option best describes Dependency Injection in Java?

A. Singleton only. B. Factory only. C. Service Locator only. D. Provide collaborators rather than constructing.

Select an answer to check.

Answer: Provide collaborators rather than constructing.

In this case, Provide collaborators rather than constructing. is correct. Spring is a DI container. This is the most accurate statement for which option best describes dependency injection in java. The remaining choices fail because they don’t satisfy the full definition.

Q98. What is the primary purpose of Dependency Injection?

A. Service Locator only. B. Singleton only. C. Provide collaborators rather than constructing. D. Factory only.

Select an answer to check.

Answer: Provide collaborators rather than constructing.

The best option here is Provide collaborators rather than constructing.. Spring is a DI container. This is the most accurate statement for what is the primary purpose of dependency injection. The remaining choices fail because they don’t satisfy the full definition.

Q99. Which statement about Dependency Injection is most accurate?

A. Provide collaborators rather than constructing. B. Factory only. C. Service Locator only. D. Singleton only.

Select an answer to check.

Answer: Provide collaborators rather than constructing.

For this question, Provide collaborators rather than constructing. is correct. Spring is a DI container. This is the most accurate statement for which statement about dependency injection is most accurate. The remaining choices fail because they don’t satisfy the full definition.

Q100. How is Dependency Injection best characterized?

A. Singleton only. B. Service Locator only. C. Provide collaborators rather than constructing. D. Factory only.

Select an answer to check.

Answer: Provide collaborators rather than constructing.

Provide collaborators rather than constructing. is the correct answer here. Spring is a DI container. This is the most accurate statement for how is dependency injection best characterized. The remaining choices fail because they don’t satisfy the full definition.