Java Programming Practice Test for Beginners

Welcome readers, we’ve brought you an entirely new Java programming practice test to polish your Java coding skills. The aim of this Java quiz is mainly to test your coding skills and logical ability. We have powered this quick Java online test with the top Java coding questions. The quality and the correctness is made sure for all the questions and answers. Most of the questions relate to programming with a little mix of core Java concepts. You will just need to focus and execute the code fragment to make the right choice. This type of Java programming practice test is very useful for readers who’ve recently started working with Java. And have read a lot of online Java tutorials. But they lack practice of Java to be able to crack a job interview or to show them as a strong candidate in the existing job profile.

It is important to mention that we’ve given our best efforts to make this Java quiz as productive as it could be. And all the programming questions are chosen after due diligence ensuring quality and competency. If any of you’ve just started learning Java and want to evaluate his/her core skills. Then, we recommend you to go through the following entry level Java quiz first. It’ll help you strengthen your grasp of the Java language.

Java Programming Practice Test for Beginners.

For your information, please note that this Java Programming Online Test has only single choice questions. We suggest to please carefully attempt all the questions. Press the below Start quiz button to go ahead.

Java Programming Practice Test.

Java Programming Practice Test.

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Note: You can see all the answers at the end of this quiz. To learn more about Java programming, please refer the on-line Java learning documentation.

We wish this Java programming practice test would help the aspiring software developers and testers in learning and finding confidence in their Java coding skills. We sincerely wish them success and thank them for attempting this Java quiz. Subsequently, we suggest you not just stop after the quiz instead check out some other amazing quizzes and tutorial on Java/Python/Selenium and related programming articles on our blog. Some of them are listed below which you can read and go for an interview with full preparation.

1- Learn A-z of Java Strings – read this.

40 Best Java Strings interview questions for Java programmers.

2- Test your Java Collections Knowledge – read this.

Top Java collection interview questions for experienced.

3. Java ProcessBuilder demo to launch a batch file – read this.

How to run a batch file using Java ProcessBuilder.

We firmly believe in sharing knowledge and listening to our readers, we request them to leave their feedbacks and questions in the comment space below and tell us what they think. To make the most of this Java quiz, we’ve some basic yet important Java programming concepts to share with our readers.

1. What is JVM? Why is Java called the ‘Platform Independent Programming Language’?

JVM, or the Java Virtual Machine, is an interpreter which accepts ‘Bytecode’ and executes it. Java primarily works on the notion of ‘compile once, run everywhere’.

  • The Java Compiler (javac) produces ‘Bytecode’ which itself is not executable. It is a highly optimized set of instructions to be interpreted by the Java Virtual Machine (JVM).
  • The translation into Bytecode makes a program compatible to run on many platforms. We then need a JVM to execute the bytecode that turns Java in a ‘Platform Independent’ language.

2. What is the Difference between JDK and JRE?

  • JDK is the short form for Java Development Kit. It is a software package that provides you resources to create Java-based software.
  • JRE is the Java Runtime Environment. JRE is an application of the Java Virtual Machine and responsible for running the Java programs.

3. What does the ‘static’ keyword mean?

The static variable in Java is associated with a class, not with the objects of the class. It is being allocated memory during the loading of the class.

Similarly, a static method belongs to a class, not to the object of the class. Without the need for creating the instance of the class, a static method can be invoked. A static method can also access static data member and updates its value.

4. What do you understand of Autoboxing and Unboxing?

The automatic conversion of primitive data types into similar Wrapper type is known as autoboxing. If the conversion goes the other way, it’ll be called unboxing. This feature eliminates the need for writing the conversion code.

5. What is the difference between Errors, Unchecked Exception, and Checked Exception?

  • An Unchecked Exception inherits from the RuntimeException. JVM has to handle them.
  • A Checked Exception inherits from the Exception class. It’s your Java code that has to handle the checked exceptions either in a try-catch clause or has to be thrown for the Super class to catch the same.
  • Errors usually occur in the case of more serious problems like the OutOfMemoryError (OOM). These may not be so easy to handle.

6. What is the difference between Throw and Throws in Java Exception Handling?

In Java programming, programmers use throw keyword to throw an Exception. However, the throws keyword is used with method signature to indicate that there may occur an exception in this method.

At the end of this Java programming practice test, we leave you with some special Java programming tips.

1. Always return empty Collections and Arrays instead of null.

While returning a collection element or an array, a method should always return it as empty instead of null. It will save a lot of if-else checks for null elements.

2. Prevent creating useless objects and prefer Lazy Initialization.

Object creation in Java is one of the costlier operation in terms of memory usage and performance impact.

3. Never declare an instance field of the class public.

A suitable approach is to make the field private and provide getter/setter methods to manage the elements.

4. Always try to reduce the Mutability of a class.

Excessive immutability can hit performance of your Java application. First determine whether you need a class to be immutable or not. Then apply the same tactics while adding the members to the class.

5. Always try to minimize the scope of a local variable.

Restricting the scope of a local variable will make the code more readable, less error-prone and improves maintainability.

See what Linus Torvalds the founding father of Linux has to say about Programmers.

“Most good programmers do programming not because they expect to get paid or get adulation by the public, but because it is fun to program.”

Lastly, please share this amazing Java programming practice test with your friends and on the social media platforms of your choice.

All the Best!