Java Programming

Java MCQ: Which of the following best describes the difference between Java Records and Lombok? a) Lombok generates boilerplate code using annotations, while records are a built-in language feature b) Lombok is used only for testing, while records are used in production code c) Lombok is part of the Java standard library, while records are […]

Java MCQ: How can Java Records be used with Spring Boot applications? a) As a replacement for all Spring Beans b) To define immutable data transfer objects (DTOs) c) To replace all Spring Controllers d) As a substitute for the application.properties file Answer: b) To define immutable data transfer objects (DTOs) Explanation: Java Records can

Java MCQ: Which of the following is true about the constructors in Java Records? a) Records cannot have custom constructors b) Records can only have parameterless constructors c) Records can have custom constructors that validate input or compute derived fields d) Records must have at least two constructors Answer: c) Records can have custom constructors

Java MCQ: What is the output of the following code snippet involving a Java Record? public record Point(int x, int y) {} public class Main { public static void main(String[] args) { Point p1 = new Point(1, 2); Point p2 = new Point(1, 2); System.out.println(p1.equals(p2)); } } a) true b) false c) Compilation error d)

Java MCQ: How do records differ from traditional classes in Java? a) Records are mutable by default, while classes are immutable by default b) Records automatically generate methods like equals(), hashCode(), and toString() c) Records cannot implement interfaces d) Records support inheritance, while classes do not Answer: b) Records automatically generate methods like equals(), hashCode(),

Java MCQ: What is the primary purpose of Java Records? a) To create mutable data structures b) To simplify the creation of immutable data classes c) To enhance performance d) To replace all existing classes Answer: b) To simplify the creation of immutable data classes Explanation: The primary purpose of Java Records is to simplify

Java MCQ: Which method is used to obtain the superclass of a class using Java Reflection? a) getSuperclass() b) getParentClass() c) getBaseClass() d) getSuperClass() Answer: a) getSuperclass() Explanation: The getSuperclass() method in Java is used to obtain the superclass of a class using reflection. This method is part of the Class class and returns a

Java MCQ: Which utility method in Java Reflection is used to check if a class is an array type? a) isArray() b) isArrayType() c) checkArray() d) isArrayClass() Answer: a) isArray() Explanation: The isArray() method in Java is used to check if a class is an array type. This method is part of the Class class

Java MCQ: How can you access the enum constants of an enum type using Java Reflection? a) getEnumConstants() b) getEnumValues() c) getConstants() d) getEnums() Answer: a) getEnumConstants() Explanation: The getEnumConstants() method in Java is used to access the enum constants of an enum type using reflection. This method is part of the Class class and

Java MCQ: How can you retrieve the length of an array using Java Reflection? a) getArrayLength() b) length() c) getLength() d) arrayLength() Answer: c) getLength() Explanation: The getLength() method in the java.lang.reflect.Array class is used to retrieve the length of an array using Java Reflection. This method is particularly useful when working with arrays of

Java MCQ: Which method is used to create an instance of a class using its constructor with Java Reflection? a) newInstance() b) create() c) construct() d) build() Answer: a) newInstance() Explanation: The newInstance() method in Java is used to create a new instance of a class using its constructor via reflection. This method is part

Java MCQ: Which method is used to access a private field using Java Reflection? a) getField() b) getDeclaredField() c) getPrivateField() d) accessField() Answer: b) getDeclaredField() Explanation: The getDeclaredField() method in Java is used to access a private field of a class using reflection. This method is part of the Class class and returns a Field

Java MCQ: Which method is used to invoke a method on an object using Java Reflection? a) invokeMethod() b) call() c) execute() d) invoke() Answer: d) invoke() Explanation: The invoke() method in Java is used to invoke a method on an object using reflection. This method is part of the Method class, which is found

Java MCQ: Which class is used to obtain information about a class in Java Reflection? a) ClassInfo b) ClassInspector c) Class d) ReflectionClass Answer: c) Class Explanation: The Class class in Java is the primary class used to obtain information about a class in Java Reflection. The Class class is part of the java.lang package

Java MCQ: What is the primary purpose of the Java Reflection API? a) To allow code reusability b) To enable dynamic inspection and manipulation of classes, methods, and fields at runtime c) To improve performance d) To simplify syntax Answer: b) To enable dynamic inspection and manipulation of classes, methods, and fields at runtime Explanation:

Java MCQ: Which class is used to compress files into ZIP format in Java? a) ZipOutputStream b) ZipFile c) ZipCompressor d) ZipWriter Answer: a) ZipOutputStream Explanation: The ZipOutputStream class in Java is used to compress files into the ZIP format. It is part of the java.util.zip package and provides methods to write compressed data to

Java MCQ: How do you read an object from a file in Java? a) readObject() b) loadObject() c) deserializeObject() d) restoreObject() Answer: a) readObject() Explanation: The readObject() method in Java is used to read an object from a file, enabling the process of deserialization. Deserialization is the reverse process of serialization, where a byte stream

Java MCQ: How do you write an object to a file in Java? a) writeObject() b) saveObject() c) serializeObject() d) storeObject() Answer: a) writeObject() Explanation: The writeObject() method in Java is used to write an object to a file, enabling the process of serialization. Serialization is the process of converting an object into a byte

Java MCQ: How do you get the size of a file in bytes using Java? a) getSize() b) size() c) length() d) fileSize() Answer: c) length() Explanation: The length() method in Java is used to get the size of a file in bytes. It is a method of the File class, which is part of

Java MCQ: Which class is used to read data from a file using DataInputStream in Java? a) DataReader b) DataInputStream c) FileInputStream d) BufferedInputStream Answer: b) DataInputStream Explanation: The DataInputStream class in Java is used to read primitive data types from an input stream in a machine-independent way. It is part of the java.io package

Java MCQ: Which method is used to read a file using BufferedInputStream in Java? a) read() b) readBytes() c) readLine() d) readData() Answer: a) read() Explanation: The read() method in Java is used to read data from a file using the BufferedInputStream class. BufferedInputStream is part of the java.io package and is used to read

Java MCQ: Which method is used to read a file using BufferedReader in Java? a) readLine() b) read() c) readFile() d) readText() Answer: a) readLine() Explanation: The readLine() method in Java is used to read a file line by line using the BufferedReader class. BufferedReader is part of the java.io package and is used to

Java MCQ: Which method is used to append data to an existing file in Java? a) appendFile() b) write() c) append() d) writeTo() Answer: b) write() Explanation: The write() method can be used to append data to an existing file in Java when used with the appropriate constructor of FileWriter or BufferedWriter. When creating a

Java MCQ: Which method is used to rename a file in Java? a) renameFile() b) rename() c) renameTo() d) changeName() Answer: c) renameTo() Explanation: The renameTo() method in Java is used to rename a file or directory. It is a method of the File class, which is part of the java.io package. This method allows

Java MCQ: Which method is used to move a file in Java? a) moveFile() b) move() c) Files.move() d) FileUtils.move() Answer: c) Files.move() Explanation: The Files.move() method, available in the java.nio.file package, is used to move files or directories from one location to another in Java. This method can also be used to rename files