Virtual Labs

Exception Handling and Parameterized Polymorphism

1. Which of the following statements is true about parameterized constructors in Java?

a: Parameterized constructors have no arguments. Explanation

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b: Parameterized constructors are called using the new keyword. Explanation

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c: Parameterized constructors have parameters that are used to initialize instance variables. Explanation

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d: Parameterized constructors are used to create static objects. Explanation

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2. Which of the following statements is true about the number of parameterized constructors that can be defined for a class in Java?

a: A class can have only one parameterized constructor Explanation

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b: A class can have multiple parameterized constructors, but they must have the same number of parameters. Explanation

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c: A class can have multiple parameterized constructors, with different numbers and types of parameters. Explanation

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d: A class cannot have parameterized constructors. Explanation

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3. Which of the following statements is true about default constructors and parameterized constructors in Java?

a: A class can have both a default constructor and a parameterized constructor. Explanation

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b: If a class has a parameterized constructor, it cannot have a default constructor. Explanation

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c: If a class has a default constructor, it cannot have a parameterized constructor. Explanation

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d: Default constructors and parameterized constructors are the same thing. Explanation

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4. What is the correct way to declare a generic class in Java?

a: class MyClass(T) { /* ... */ } Explanation

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b: class MyClass { /* ... */ } Explanation

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c: class MyClass[T] { /* ... */ } Explanation

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d: class MyClass{T} { /* ... */ } Explanation

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5. Which of the following statements about Java Generics and parameterized types is incorrect?

a: Generics shift more type checking responsibilities to the compiler, enhancing type safety. Explanation

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b: Generics eliminate the need for downcasts when working with Java Collections. Explanation

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c: Generics can be used with primitive types directly (e.g., List). Explanation

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d: Wildcards (?) are used in generics to represent unknown types. Explanation

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