Java Programming

Java MCQ: Which of these cannot be used for a variable name in Java? a) identifier b) keyword c) variable d) method Answer: b) keyword Explanation: In Java, keywords cannot be used as variable names because they have predefined meanings in the language. Examples of keywords include int, class, public, and void. Reference links: https://www.rameshfadatare.com/learn-java-programming/ […]

Java MCQ: Which one of the following is not a Java feature? a) Object-oriented b) Use of pointers c) Portable d) Dynamic Answer: b) Use of pointers Explanation: Java does not support the use of pointers, unlike C or C++. Pointers can lead to complex code and security vulnerabilities, which is why Java manages memory

Java MCQ: Which component is used to compile, debug and execute Java programs? a) JDK b) JRE c) JVM d) IDE Answer: a) JDK Explanation: The Java Development Kit (JDK) is the software development environment used to compile, debug, and execute Java programs. It includes the Java compiler, libraries, and tools necessary for Java development.

Java MCQ: Which statement is true about Java? a) Java is platform-independent b) Java is a procedure-oriented programming language c) Java does not support multithreading d) Java does not support the development of web applications Answer: a) Java is platform-independent Explanation: Java is platform-independent due to its use of the Java Virtual Machine (JVM), which

Java MCQ: Who invented Java Programming? a) James Gosling b) Dennis Ritchie c) Bjarne Stroustrup d) Guido van Rossum Answer: a) James Gosling Explanation: James Gosling, often referred to as the “father of Java,” invented Java programming language in 1995 while working at Sun Microsystems. Java was designed to be a platform-independent, object-oriented language with

Java MCQ: Which of the following is used to find and fix bugs in the program? a) Debugger b) Compiler c) JVM d) Interpreter Answer: a) Debugger Explanation: A debugger is a tool that is used to find and fix bugs in a program. It allows the developer to run the program step-by-step, inspect variables,

Java MCQ: What does the operator >>> do? a) Zero-fill right shift b) Signed right shift c) Left shift d) Signed left shift Answer: a) Zero-fill right shift Explanation: The >>> operator in Java is the zero-fill right shift operator. It shifts the bits of the operand to the right and fills the leftmost bits

Java MCQ: Which of the following statements are true about the finalize() method? a) It is called before an object is garbage collected b) It can be overridden in a subclass c) It is used to clean up resources before object destruction d) All of the above Answer: d) All of the above Explanation: All

Java MCQ: Identify the interface which is used to declare core methods in Java? a) java.lang.Object b) java.util.List c) java.lang.Runnable d) java.lang.Comparable Answer: d) java.lang.Comparable Explanation: The Comparable interface in Java is used to declare core methods for comparing objects. It defines the compareTo() method, which allows objects to be ordered. This interface is essential

Java MCQ: Where is the System class defined? a) java.lang package b) java.util package c) java.io package d) java.net package Answer: a) java.lang package Explanation: The System class is defined in the java.lang package, which is automatically imported into every Java program. This class provides access to system resources such as standard input, output, and

Java MCQ: Which of the following exception is thrown when a divide by zero statement is executed? a) ArithmeticException b) NullPointerException c) IOException d) ClassNotFoundException Answer: a) ArithmeticException Explanation: In Java, ArithmeticException is thrown when an exceptional arithmetic condition occurs, such as dividing by zero. This is a common runtime exception that does not require

Java MCQ: Exception created by try block is caught in which block? a) catch b) throw c) finally d) finalize Answer: a) catch Explanation: In Java, exceptions that are thrown within a try block are caught and handled by the corresponding catch block. The catch block allows you to define a response to the specific

Java MCQ: What is Runnable? a) An interface b) A class c) A method d) A package Answer: a) An interface Explanation: The Runnable interface in Java is used to define a task that can be executed by a thread. It has a single method, run(), that must be implemented by any class that implements

Java MCQ: When is the finalize() method called? a) Before garbage collection b) After garbage collection c) Before object creation d) After object creation Answer: a) Before garbage collection Explanation: The finalize() method is called by the garbage collector on an object when it determines that there are no more references to the object. It

Java MCQ: What is the implicit return type of a constructor? a) No return type b) void c) Object d) Class type Answer: a) No return type Explanation: Constructors in Java do not have a return type, not even void. They are used to initialize objects when they are created, and the return type is

Java MCQ: What is the variables declared in a class for the use of all methods of the class called? a) Instance variables b) Local variables c) Static variables d) Global variables Answer: a) Instance variables Explanation: Instance variables are declared within a class but outside of any method. They are used by all methods

Java MCQ: Identify the modifier which cannot be used for constructors. a) private b) protected c) final d) public Answer: c) final Explanation: The final modifier cannot be applied to constructors in Java because constructors are not inherited, and hence, there’s no point in preventing inheritance. Other access modifiers like private, protected, and public can

Java MCQ: Where does the system store parameters and local variables whenever a method is invoked? a) Stack b) Heap c) Array d) LinkedList Answer: a) Stack Explanation: In Java, parameters and local variables are stored in the stack memory whenever a method is invoked. The stack memory is used for execution of a thread

Java MCQ: What is the output of Math.floor(3.6)? a) 3.0 b) 4.0 c) 3.6 d) 3 Answer: a) 3.0 Explanation: The Math.floor() method in Java returns the largest integer that is less than or equal to the argument passed. For Math.floor(3.6), it returns 3.0. Reference links: https://www.rameshfadatare.com/learn-java-programming/ https://www.javaguides.net/p/java-tutorial-learn-java-programming.html

Java MCQ: Identify the return type of a method that does not return any value. a) void b) int c) double d) null Answer: a) void Explanation: In Java, the void keyword is used as the return type of a method that does not return any value. This indicates that the method performs an action

Java MCQ: Total constructors in the String class have? a) 13 b) 10 c) 12 d) 15 Answer: c) 12 Explanation: The String class in Java has 12 constructors that allow for the creation of strings in various ways, such as from arrays of bytes, characters, and string literals. Reference links: https://www.rameshfadatare.com/learn-java-programming/ https://www.javaguides.net/p/java-tutorial-learn-java-programming.html

Java MCQ: How many String objects will be created in the following code? a) 1 b) 2 c) 3 d) 4 Answer: a) 1 Explanation: When a String is created using a string literal, only one String object is created in the string pool, if no other object with the same content exists. Reference links:

Java MCQ: compareTo() returns? a) Positive integer, zero, or negative integer b) True or false c) 1 or -1 d) None of the above Answer: a) Positive integer, zero, or negative integer Explanation: The compareTo() method in Java returns a positive integer, zero, or a negative integer based on whether the object is greater than,

Java MCQ: In which of the following is toString() method defined? a) java.lang.Object b) java.lang.String c) java.lang.util d) java.lang.Class Answer: a) java.lang.Object Explanation: The toString() method is defined in the java.lang.Object class, which is the superclass of all classes in Java. This method is often overridden to provide a string representation of an object. Reference

Java MCQ: When is the object created with the new keyword? a) At runtime b) At compile-time c) Depends on the code d) None of the above Answer: a) At runtime Explanation: In Java, objects are created at runtime when the new keyword is used. This is when memory is allocated for the new object,