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Java MCQ: Which of the following best describes the concept of inheritance in Java? a) Inheritance allows a class to inherit methods and fields from multiple classes b) Inheritance allows a class to inherit methods and fields from a single superclass c) Inheritance is not supported in Java d) Inheritance allows a class to override […]

Java MCQ: Which of the following is a feature of the ‘synchronized’ keyword in Java? a) It allows multiple threads to access a resource simultaneously b) It prevents multiple threads from accessing a resource simultaneously c) It is used to initialize a thread d) It is used to terminate a thread Answer: b) It prevents

Java MCQ: What is the purpose of the ‘instanceof’ keyword in Java? a) To check if an object is an instance of a class or subclass b) To cast an object to a different type c) To compare two objects for equality d) To create a new instance of a class Answer: a) To check

Java MCQ: Which of the following is true about the ‘finalize()’ method in Java? a) The ‘finalize()’ method is called to initialize an object b) The ‘finalize()’ method is called by the garbage collector before an object is destroyed c) The ‘finalize()’ method can be overridden to implement object cloning d) The ‘finalize()’ method is

Java MCQ: Which of the following best describes method overriding in Java? a) Method overriding occurs when two methods in the same class have the same name but different parameter lists b) Method overriding is the process of defining a method in a subclass that has the same signature as a method in its superclass

Java MCQ: Which of the following statements about the ‘abstract’ keyword in Java is true? a) An abstract class cannot have any methods b) An abstract method must be implemented in a subclass c) An abstract class can be instantiated directly d) An abstract method can have a body Answer: b) An abstract method must

Java MCQ: Which of the following is true about the ‘volatile’ keyword in Java? a) It ensures that a variable’s value is read from main memory, not from a thread’s local cache b) It prevents multiple threads from accessing a variable simultaneously c) It guarantees that a variable cannot be modified d) It is used

Java MCQ: Which of the following is not a feature of the Java programming language? a) Platform-independent b) Object-oriented c) Pointer-based d) Multithreaded Answer: c) Pointer-based Explanation: Java is a platform-independent, object-oriented, and multithreaded programming language, but it does not support pointers. Pointers are used in languages like C and C++ to directly access memory

Java MCQ: Which of the following best describes the purpose of a constructor in Java? a) To destroy an object when it is no longer needed b) To initialize an object when it is created c) To return a new instance of the class d) To create a copy of an object Answer: b) To

Java MCQ: Which of the following is true about encapsulation in Java? a) Encapsulation allows internal implementation to be hidden from the user b) Encapsulation is achieved using access modifiers c) Encapsulation makes code more flexible and maintainable d) All of the above Answer: d) All of the above Explanation: Encapsulation in Java is the

Java MCQ: What does the ‘implements’ keyword do in Java? a) It is used to inherit a class b) It is used to implement an interface c) It is used to override a method d) It is used to define an abstract method Answer: b) It is used to implement an interface Explanation: The implements

Java MCQ: What is the purpose of the ‘this’ keyword in Java? a) To refer to the current class instance b) To refer to the superclass instance c) To call a method in the superclass d) To return an instance of the superclass Answer: a) To refer to the current class instance Explanation: In Java,

Java MCQ: Which of the following statements about Java constructors is true? a) Constructors must have a return type b) Constructors can be abstract c) Constructors cannot be synchronized d) Constructors do not have a return type Answer: d) Constructors do not have a return type Explanation: Constructors in Java are special methods used to

Java MCQ: Which of the following is true about the ‘final’ keyword in Java? a) The final keyword can be applied to classes, methods, and variables b) A final method cannot be overridden c) A final class cannot be subclassed d) All of the above Answer: d) All of the above Explanation: The final keyword

Java MCQ: Why is the ‘super’ keyword used in Java? a) To create a superclass b) To call a method in the current class c) To refer to the immediate parent class object d) To override a method in the superclass Answer: c) To refer to the immediate parent class object Explanation: The super keyword

Java MCQ: Which of the following is not a feature of Java? a) Dynamic b) Platform-independent c) Machine-dependent d) Multithreaded Answer: c) Machine-dependent Explanation: Java is designed to be platform-independent, meaning that Java programs can run on any device or operating system that has the Java Virtual Machine (JVM) installed. This “write once, run anywhere”

Java MCQ: Which of the following is not a valid access modifier in Java? a) private b) protected c) public d) internal Answer: d) internal Explanation: In Java, the valid access modifiers are private, protected, and public. These modifiers control the visibility of classes, methods, and variables. private makes a member accessible only within the

Java MCQ: Which of the following best describes method overloading in Java? a) Method overloading occurs when two methods in the same class have the same name but different parameter lists b) Method overloading is the process of overriding a method in a subclass c) Method overloading refers to the runtime resolution of method calls

Java MCQ: Which of the following is a characteristic of the ‘transient’ keyword in Java? a) It prevents serialization of the variable b) It ensures that the variable is serialized c) It allows the variable to be accessed from any thread d) It makes the variable immutable Answer: a) It prevents serialization of the variable

Java MCQ: Which of the following is used to handle exceptions in Java? a) if-else b) for loop c) switch-case d) try-catch Answer: d) try-catch Explanation: In Java, exceptions are handled using the try-catch block. When an exception occurs in the try block, the control is transferred to the catch block where the exception is

Java MCQ: Which of the following is true about the ‘static’ keyword in Java? a) Static methods belong to the class, not instances b) Static methods can access instance variables directly c) Static methods can be abstract d) Static methods can override instance methods Answer: a) Static methods belong to the class, not instances Explanation:

Java MCQ: Which of the following is a wrapper class in Java? a) int b) Integer c) float d) boolean Answer: b) Integer Explanation: In Java, a wrapper class is an object representation of a primitive data type. The Integer class is a wrapper class for the primitive data type int. Wrapper classes provide a

Java MCQ: Which of the following best describes polymorphism in Java? a) Polymorphism allows methods to have the same name but different parameter lists b) Polymorphism allows an object to take on many forms c) Polymorphism is implemented using the ‘extends’ keyword d) Both a and b Answer: d) Both a and b Explanation: Polymorphism

Java MCQ: Which of the following is true about inheritance in Java? a) Inheritance allows a class to inherit fields and methods from another class b) Java supports multiple inheritance through classes c) Inheritance is implemented using the ‘implements’ keyword d) Inheritance prevents method overriding Answer: a) Inheritance allows a class to inherit fields and

Java MCQ: Which of the following best describes encapsulation in Java? a) Encapsulation is the technique of bundling data and methods that operate on that data within a single unit b) Encapsulation is the process of inheriting methods from a superclass c) Encapsulation is the use of access modifiers to restrict access to data d)