Last Updated on August 22, 2024 by Abhishek Sharma
Java is one of the most widely used programming languages in the world, renowned for its platform independence, robust security features, and extensive libraries. As a critical skill for software developers, proficiency in Java is often tested in technical interviews, especially in companies like Accenture, where Java plays a pivotal role in their software development projects. Accenture’s Java language questions are designed to assess a candidate’s understanding of core Java concepts, problem-solving abilities, and practical coding skills. This article provides an overview of what to expect from Accenture’s Java interview questions, along with some frequently asked questions to help you prepare.
Accenture Java Interview Questions
So, let us begin Java Questions that have been previously asked in the Accenture Interviews.
Q1. What is the difference between a primitive type and a reference type in Java?
Ans. The main difference between primitive types and reference types is that primitive types are passed by value, while reference types are passed by reference. When a primitive type is passed as a parameter to a method or assigned to another variable, a copy of its value is created. When a reference type is passed as a parameter or assigned to another variable, a copy of its reference is created, but not a copy of the object itself. This means that changes to the object are reflected across all variables that hold a reference to it.
Q2. What is the difference between a private, protected, and public access modifier in Java?
Ans. In Java, access modifiers are used to control the visibility and accessibility of class members such as variables, methods, and inner classes. There are three access modifiers in Java: private, protected, and public.
Private access modifier limits the visibility of a member to its own class only. This means that the member cannot be accessed by any other class, even if they are in the same package. Protected access modifier allows a member to be accessed within the same package as well as in its subclasses, regardless of whether they are in the same package or not. Public access modifier allows a member to be accessed from anywhere in the program.
Q3. What is polymorphism in Java?
Ans. Polymorphism is a fundamental concept in Java that refers to the ability of an object to take on multiple forms. In Java, there are two types of polymorphism: compile-time polymorphism and run-time polymorphism.
Compile-time polymorphism is achieved through method overloading, where a class has multiple methods with the same name but different parameters. The compiler determines which method to call based on the method signature.
Run-time polymorphism is achieved through method overriding, where a subclass provides its own implementation of a method that is already defined in its superclass. The method to be called is determined at runtime based on the actual object type.
Q4. What is inheritance in Java?
Ans. Inheritance is a key concept in object-oriented programming that allows one class to inherit properties and methods from another class. In Java, a class can be defined as a subclass of another class using the "extends" keyword. The subclass inherits all the properties and methods of the superclass, and can also define additional properties and methods of its own.
Inheritance is a powerful tool for creating complex and scalable software systems, as it allows developers to reuse code and build upon existing functionality. By creating a hierarchy of classes with shared characteristics, inheritance enables more efficient and maintainable programming.
Q5. What is encapsulation in Java?
Ans. Encapsulation is a fundamental concept in Java that refers to the practice of hiding the implementation details of a class from other parts of the program. In Java, encapsulation is achieved through the use of access modifiers such as private, public, and protected.
By hiding the implementation details, encapsulation helps to protect the integrity of the program and prevent unwanted interference with the internal workings of a class. It also makes it easier to modify the implementation of a class without affecting other parts of the program, as long as the external interface of the class remains unchanged.
Encapsulation is an important principle of object-oriented programming, as it promotes the creation of robust, maintainable, and secure software systems.
Q6. What is an exception in Java?
Ans. In Java, an exception is an event that interrupts the normal flow of a program’s execution. When an unexpected situation occurs, such as a run-time error or invalid input, Java throws an exception object to signal that something has gone wrong.
Exceptions in Java are represented by classes, and there are many built-in exception classes in Java, such as the ArithmeticException, NullPointerException, and IOException classes.
Q7. What is a package in Java?
Ans. In Java, a package is a mechanism for organizing related classes and interfaces into a single namespace. A package is a collection of classes, interfaces, enums, and other packages, which helps to group related code and prevent naming conflicts.
Packages in Java are identified by a unique name, which is a sequence of identifiers separated by periods. For example, the java.util package contains utility classes for working with data structures, while the java.awt package contains classes for creating graphical user interfaces.
Packages can be accessed using the import statement, which allows classes from one package to be used in another package. By organizing related code into packages, Java promotes modularity, code reuse, and maintainability in software development.
Q8. What is the difference between a static and a non-static method in Java?
Ans. In Java, a static method is a method that belongs to a class rather than an instance of that class. It can be called without creating an instance of the class, and is shared by all instances of the class.
In contrast, a non-static method is a method that belongs to an instance of a class. It can only be called on an instance of the class, and each instance of the class has its own copy of the method.
Static methods are often used for utility methods that do not depend on the state of an object, such as the Math.sqrt() method. Non-static methods are used for methods that depend on the state of an object, such as the getName() method in a Person class.
Q9. What is a constructor in Java?
Ans. In Java, a constructor is a special method that is used to create and initialize objects of a class. When an object is created using the "new" keyword, the constructor is called automatically to set up the object’s initial state.
Constructors in Java have the same name as the class they belong to and can take zero or more parameters. They do not have a return type, not even void. They are often used to set the initial values of instance variables, which are the variables that belong to each instance of a class.
Constructors are an essential part of object-oriented programming and are used extensively in Java to create objects and manage their states.
Q10. What is method overloading in Java?
Ans. In Java, method overloading is a feature that allows a class to have multiple methods with the same name but different parameter lists. The parameters can differ in their number, order, or type.
When a method is called, the compiler determines which version of the method to use based on the number and types of the arguments passed. This allows the same method name to be used for different tasks, improving code readability and reducing code duplication.
Method overloading is a form of compile-time polymorphism, which means that the method to be called is determined by the compiler rather than at runtime. It is a powerful tool for creating flexible and maintainable code in Java.
Q11. What is the purpose of the "final" keyword in Java?
Ans. In Java, the "final" keyword is used to define constants, make variables or methods unmodifiable, and prevent the inheritance of classes or methods.
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Constants: The "final" keyword can be used to define constants, which are variables that cannot be changed after they have been initialized. This is achieved by using the "final" keyword in the declaration of the variable. For example, the following code declares a final variable called PI with a value of 3.14159:
final double PI = 3.14159; -
Unmodifiable variables or methods: The "final" keyword can also be used to make variables or methods unmodifiable. When a variable or method is marked as final, it cannot be changed or overridden by any subclass. This is useful when you want to ensure that certain properties or behaviors of an object remain consistent across the application. For example, the following code declares a final method called getName() that cannot be overridden:
public class Person { private final String name; public Person(String name) { this.name = name; } public final String getName() { return this.name; } } -
Preventing inheritance: The "final" keyword can also be used to prevent a class from being inherited by other classes. When a class is marked as final, it cannot be extended by any subclass. This is useful when you want to ensure that a certain class cannot be modified or subclassed. For example, the following code declares a final class called Animal that cannot be extended:
final public class Animal { // Class implementation }
Q12. What is a thread in Java?
Ans. In Java, a thread is a lightweight subprocess that runs concurrently with other threads within the same process. Each thread has its own call stack and can execute its own code independently of the other threads in the same process.
A thread is created by instantiating an object of the Thread class, which represents a single thread of execution. To start a thread, the start() method of the Thread class is called, which creates a new call stack for the thread and begins executing the run() method of the thread.
When a thread is started, it runs concurrently with the other threads in the same process, and its execution is controlled by the Java Virtual Machine (JVM). The JVM schedules the threads based on their priority and availability of resources, and each thread can execute its own code independently of the other threads.
Q13. What is the purpose of the "super" keyword in Java?
Ans. In Java, the "super" keyword is used to refer to the parent class of a subclass. The purpose of the "super" keyword is to access the properties and methods of the parent class from within the subclass.
When a class is derived from another class, it inherits all the properties and methods of the parent class. However, the subclass can also add its own properties and methods or override the properties and methods of the parent class.
The "super" keyword is used to access the properties and methods of the parent class that have been overridden by the subclass. For example, if a method in the parent class has been overridden by the subclass, the "super" keyword can be used to call the original implementation of the method in the parent class.
Q14. What is the difference between a checked and an unchecked exception in Java?
Ans. In Java, exceptions are used to handle unexpected situations that may occur during the execution of a program. There are two main types of exceptions: checked and unchecked exceptions.
A checked exception is an exception that must be declared in the method signature or caught by the caller. Examples of checked exceptions in Java include IOException, SQLException, and ClassNotFoundException. An unchecked exception, on the other hand, is an exception that does not have to be declared or caught. Examples of unchecked exceptions in Java include NullPointerException, ArrayIndexOutOfBoundsException, and ArithmeticException.
The main difference between checked and unchecked exceptions is that checked exceptions are typically used for recoverable errors that the program can reasonably be expected to handle, while unchecked exceptions are used for situations that are beyond the program’s control or that indicate a programming error.
When a method throws a checked exception, it indicates that the method may not be able to complete its task successfully, and the caller must handle the exception or propagate it to the next level of the call stack. This makes it easier to write reliable and robust code that can handle errors and exceptions gracefully.
Q15. What is the difference between the JDK and the JRE?
Ans. The JDK (Java Development Kit) is a software development kit that contains the tools and libraries necessary for developing Java applications. The JRE (Java Runtime Environment) is a runtime environment that allows Java programs to be executed. The main difference between the two is that the JDK includes a compiler, while the JRE does not.
Accenture Java Coding Questions
Here are some coding questions that were asked in the Accenture Interviews.
Q1. Write a Program to reverse a String in Java.
Ans.
class Main{
public static void main(String args[]){
String str = "PrepBytes";
StringBuilder sb = new StringBuilder(str);
sb.reverse();
System.out.println(sb);
}
} Output:
setyBperPQ2. Given two integers m and n, you have to print out the sum of all multiples of 7 in the range of [m,n].
Ans.
class Main{
public static void main (String[] args) {
// your code goes here
int m = 99;
int n = 115;
int ans = 0;
for(int i=m; i<=n; i++){
if(i%7==0) ans+=i;
}
System.out.println(ans);
}
} Output:
217Q3. You are given a String, and you have to print the frequencies of all characters present in the String in Alphabetical Order.
Ans.
class PrepBytes{
public static void main(String args[]){
String str = "prepbytes";
int freq[] = new int[26];
for(int i=0; i<str.length(); i++){
freq[str.charAt(i)-'a']++;
}
for(int i=0; i<26; i++){
System.out.print(freq[i]+" ");
}
}
} Output:
0 1 0 0 2 0 0 0 0 0 0 0 0 0 0 2 0 1 1 1 0 0 0 0 1 0For more coding Questions asked in Accenture, you can check out:
Top 10 Accenture Coding Questions for Placements
Conclusion
Mastering Java is essential for anyone aspiring to work in a software development role at Accenture. The interview questions focus on a range of topics, from basic syntax and object-oriented programming principles to more complex concepts like multithreading and memory management. By preparing thoroughly and understanding the type of questions that may be asked, candidates can approach their Accenture Java interview with confidence. Practice, along with a deep understanding of Java’s core concepts, will be key to success.
Frequently Asked Questions (FAQs) related to Accenture Java Language Questions
Here are some FAQs related to Accenture Java Language Questions:
1. What topics are commonly covered in Accenture’s Java interview questions?
Accenture’s Java interview questions typically cover a wide range of topics, including basic syntax, object-oriented programming principles, exception handling, collections framework, multithreading, memory management, and Java 8 features like streams and lambda expressions.
2. How important is Java proficiency for a role at Accenture?
Java proficiency is crucial for many roles at Accenture, especially those related to software development and engineering. A strong understanding of Java can significantly enhance your chances of success in the technical interview process.
3. Are Accenture’s Java interview questions more theoretical or practical?
Accenture’s Java interview questions can be a mix of both theoretical and practical. Candidates may be asked to explain concepts or solve coding problems that test their ability to apply Java knowledge in real-world scenarios.
4. What level of Java knowledge is required for Accenture interviews?
The level of Java knowledge required can vary depending on the role. However, candidates should be well-versed in both fundamental and advanced Java concepts, as the questions can range from basic to more complex topics.
5. How can I best prepare for Accenture’s Java interview questions?
To prepare for Accenture’s Java interview questions, review core Java concepts, practice coding problems, and understand how to apply Java in solving real-world challenges. Additionally, studying past interview questions and participating in mock interviews can be very beneficial.