Java Programming

Java MCQ: How can you copy a file in Java? a) Using copyFile() method b) Using Files.copy() method c) Using FileUtils.copy() method d) Using copy() method of File class Answer: b) Using Files.copy() method Explanation: The Files.copy() method, available in the java.nio.file package, is used to copy files or directories in Java. This method provides […]

Java MCQ: Which method is used to delete a file in Java? a) deleteFile() b) removeFile() c) delete() d) eraseFile() Answer: c) delete() Explanation: The delete() method in Java is used to delete a file or an empty directory. It is a method of the File class, which is part of the java.io package. When

Java MCQ: Which method is used to write data to a file in Java? a) writeFile() b) write() c) writeBytes() d) writeToFile() Answer: b) write() Explanation: The write() method in Java is commonly used to write data to a file. This method is available in several classes, such as FileWriter, BufferedWriter, and OutputStream, each serving

Java MCQ: Which method is used to create a file in Java? a) createFile() b) newFile() c) createNewFile() d) makeFile() Answer: c) createNewFile() Explanation: The createNewFile() method in Java is used to create a new file. It is a method of the File class, which is part of the java.io package. When you call createNewFile(),

Java MCQ: What is the purpose of wildcards in Java Generics? a) To allow flexibility in specifying types b) To enforce strict type constraints c) To convert types at runtime d) To eliminate the need for type parameters Answer: a) To allow flexibility in specifying types Explanation: Wildcards in Java Generics are used to allow

Java MCQ: What is a bounded type parameter in Java Generics? a) A type parameter that is restricted to a specific set of types b) A type parameter that can only be used with primitive types c) A type parameter that is automatically inferred d) A type parameter that does not allow null values Answer:

Java MCQ: Which of the following is true about generic methods in Java? a) They can be defined with a type parameter that is specified at the method level b) They can only operate on objects of a specific type c) They cannot be overloaded d) They are less flexible than regular methods Answer: a)

Java MCQ: What does a generic type in Java allow? a) The creation of a class, interface, or method that works with any data type b) The automatic conversion of data types c) The creation of methods with multiple return types d) The use of primitive data types only Answer: a) The creation of a

Java MCQ: Which of the following is NOT a benefit of using Generics in Java? a) Code reusability b) Runtime type checking c) Type safety d) Elimination of type casting Answer: b) Runtime type checking Explanation: Generics in Java offer several benefits, including code reusability, type safety, and the elimination of explicit type casting. However,

Java MCQ: What is the primary purpose of Generics in Java? a) To allow code reusability and type safety b) To increase performance c) To simplify syntax d) To avoid using collections Answer: a) To allow code reusability and type safety Explanation: The primary purpose of Generics in Java is to provide a mechanism for

Java MCQ: Which class provides system-independent server-side implementation? a) Socket b) ServerSocket c) DatagramSocket d) None of the above Answer: b) ServerSocket Explanation: The ServerSocket class in Java provides a system-independent mechanism for server-side socket communication. It listens for requests on a specified port and establishes a connection with clients. Reference links: https://www.rameshfadatare.com/learn-java-programming/ https://www.javaguides.net/p/java-tutorial-learn-java-programming.html

Java MCQ: What is the numerical range of a char data type in Java? a) 0 to 32767 b) 0 to 65535 c) 0 to 256 d) 0 to 1024 Answer: b) 0 to 65535 Explanation: The char data type in Java is a 16-bit Unicode character. The numerical range of char is from 0

Java MCQ: Which one of the following is not an access modifier? a) protected b) void c) private d) public Answer: b) void Explanation: void is not an access modifier; it is a return type used for methods that do not return any value. The access modifiers in Java are public, protected, private, and the

Java MCQ: Which of these keywords is used for the block to be examined for exceptions? a) try b) catch c) throw d) throws Answer: a) try Explanation: The try block is used in Java to specify a block of code that will be examined for exceptions. If an exception is thrown within this block,

Java MCQ: Which of these statements is incorrect about Thread? a) run() method is used to begin execution of a thread b) run() method is called automatically after the start() method is called c) A thread can be created by implementing Runnable interface and overriding the run() method d) A thread can be created by

Java MCQ: Which of these packages contains the exception StackOverflow in Java? a) java.lang b) java.util c) java.io d) java.net Answer: a) java.lang Explanation: The StackOverflowError in Java is part of the java.lang package. It is thrown when a stack overflow occurs because an application recurses too deeply. Reference links: https://www.rameshfadatare.com/learn-java-programming/ https://www.javaguides.net/p/java-tutorial-learn-java-programming.html

Java MCQ: Which of these keywords is used to define interfaces in Java? a) interface b) intf c) implement d) None of the above Answer: a) interface Explanation: The interface keyword in Java is used to define an interface, which is a reference type that can contain only abstract methods, static methods, default methods, and

Java MCQ: Which of these are selection statements in Java? a) if b) switch c) break d) a and b Answer: d) a and b Explanation: The if and switch statements in Java are selection statements that allow the program to make decisions and execute specific blocks of code based on conditions. Reference links: https://www.rameshfadatare.com/learn-java-programming/

Java MCQ: Which exception is thrown when Java is out of memory? a) MemoryError b) OutOfMemoryError c) NullPointerException d) IOException Answer: b) OutOfMemoryError Explanation: When the Java Virtual Machine (JVM) runs out of memory, it throws an OutOfMemoryError. This error indicates that the JVM cannot allocate an object because it is out of memory and

Java MCQ: What is the extension of compiled Java classes? a) .js b) .class c) .java d) .exe Answer: b) .class Explanation: Compiled Java classes are stored in files with the .class extension. These files contain bytecode, which can be executed by the Java Virtual Machine (JVM). Reference links: https://www.rameshfadatare.com/learn-java-programming/ https://www.javaguides.net/p/java-tutorial-learn-java-programming.html

Java MCQ: What is Truncation in Java? a) Removing decimal part from a number b) Rounding off a number c) Converting float to int d) None of the above Answer: a) Removing decimal part from a number Explanation: Truncation in Java refers to the process of removing the fractional part (decimal part) from a number,

Java MCQ: What is not the use of the “this” keyword in Java? a) Referring to the current class instance variable b) Invoking the current class constructor c) Invoking the current class method d) Passing itself to the method Answer: c) Invoking the current class method Explanation: The this keyword in Java is used to

Java MCQ: Which of the following is not an OOPS concept in Java? a) Inheritance b) Encapsulation c) Polymorphism d) Compilation Answer: d) Compilation Explanation: Compilation is not an object-oriented programming (OOP) concept. The main OOP concepts in Java are Inheritance, Encapsulation, Polymorphism, and Abstraction. Reference links: https://www.rameshfadatare.com/learn-java-programming/ https://www.javaguides.net/p/java-tutorial-learn-java-programming.html

Java MCQ: Which environment variable is used to set the Java path? a) JAVA_HOME b) PATH c) CLASSPATH d) JRE_HOME Answer: a) JAVA_HOME Explanation: The JAVA_HOME environment variable is used to set the path to the Java Development Kit (JDK) installation directory. This variable is often required by Java applications to locate the correct Java

Java MCQ: What is the extension of Java code files? a) .js b) .txt c) .class d) .java Answer: d) .java Explanation: Java source code files have the extension .java. These files are compiled by the Java compiler into bytecode files with the extension .class. Reference links: https://www.rameshfadatare.com/learn-java-programming/ https://www.javaguides.net/p/java-tutorial-learn-java-programming.html