
6 1Z0-830 Practice Questions and Mock Tests for Java 21 Devs
Description
Preparing for Java 21 Certification and looking for practice questions to increase your speed and accuracy, then you have come to the right place. In this Udemy course, I am going to share more than 250+ questions divided into 6 practice tests to prepare you thoroughly for all the exam topics tested in the Java 1Z0-830 exam for Java 21 developers.
Honestly speaking, this exam is one of the toughest exam I have come across. I have given and passed multiple Java certification starting from SCJP 4 to Java 17 but this one is toughest of them all because of the number of concepts they are testing on a single question.
Some questions were really long, like you need to spend one or two minutes to truly understand what's going on, and then you may have 8 to 10 options, which increases the chances of missing any correct option. I mean, there is no way you can solve these questions in a limited time if you have not practiced enough.
That's why the importance of practice questions and mock exams is even greater for 1Z0-830, and I am trying to help with this course.
This is a practice test course to prepare for the Java SE 21 Developer Professional Exam 1Z0-830 in 2025. This practice test course has 5 full-length tests with 50+ questions on each to test your preparation. They are great to build the speed and accuracy required to crack this certification in the first attempt.
Each practice questions comes with explanation and you can use them to find your strong and weak areas before actual example. Udemy also allows you to see topic where you are scoring high and where you need more practice.
The real exam will have 50 questions, and you will have 120 minutes or 2 hours to solve them, which means you will get approximately 2 minutes for each question.
In these 2 minutes, you will not just need to read the question and understand it, but also read all options and understand them as well.
Many people struggle to do this because of a lack of practice, and that's where these practice tests or mock tests help you, and you really need them if you want to crack 1Z0-830, which is one of the toughest Java certifications so far.
You can guess it from the simple fact that compared to Java 17 Professional Exam 1Z0-829, this certification has more time, 120 minute,s compared to 90 minutes for solving the same number of questions, 50. Why would they give you more time?
Well, because each question is much longer, lengthy, complex, and has up to 4 to 10 options to choose from.
Because of that, even after adding 30 minutes, many people will struggle to solve 34 questions correctly, which is required to pass this exam.
Here are a few important points about Java SE 21 Professional Exam or OCP 21 with code 1Z0-830
You need to solve 50 questions in 120 minutes
The passing mark is 68%, which means you need to solve 34 questions correctly
Questions are very long,g you may need to scroll to see them fully, which can take a lot of time
The number of options has increased; you can have from 4 to 10 options to choose from
There is no question from the topic removed from 1Z0-830 compared to 1Z0-829, like JDBC, Secure Coding, and Annotations.
Questions are complex and test multiple topics at the same time.
A few important topics are modules, streams, records, var, pattern matching with switch, and virtual threads
In order to prepare well for 1Z0-830, I suggest you solve as many questions as possible to build the speed and accuracy required to pass this exam on your first attempt.
Ideally, you should do them in a quiet place, more like a real exam scenario, and try to finish them within time. This will allow you to judge your preparation level.
I have also included slightly more than 50 questions in each practice test to push you a bit more, as those last-minute pushes make a big difference. So you will solve more than 50 questions in 120 minutes to prepare better for the exam.
Each practice test is a full-length test and covers all exam topics, but the focus is given on Java SE 21 new features like Virtual threads and scoped variables, wherever possible.
You will find many questions on virtual threads and scoped variables in this test, along with modules, Stream API, Collection API, and other topics.
So, look forward to seeing you inside the test.
If you have any questions or doubts while doing the test, feel free to message me in Q&A, and I will try my best to answer and help you out.
All the best with your 1Z0-830 exam, and I wish you to score 100/100
Exam Objectives
Here are all the Exam objectives that will be tested in the exam, and I have tried to cover all of them in these practice questions and mock tests.
Handling Date, Time, Text, Numeri,c and Boolean Values
Use primitives and wrapper classes. Evaluate arithmetic and boolean expressions, using the Math API and by applying precedence rules, type conversions, and casting.
Manipulate text, including text blocks, using String and StringBuilder classes.
Manipulate date, time, duration, period, instant, and time-zone objects, including daylight saving time using Date-Time API.
Controlling Program Flow
Create program flow control constructs including if/else, switch statements and expressions, loops, and break and continue statements.
Using Object-Oriented Concepts in Java
Declare and instantiate Java objects, including nested class objects, and explain the object life-cycle, including creation, reassigning references, and garbage collection.
Create classes and records, and define and use instance and static fields and methods, constructors, and instance and static initializers.
Implement overloaded methods, including var-arg methods.
Understand variable scopes, apply encapsulation, and create immutable objects. Use local variable type inference.
Implement inheritance, including abstract and sealed types as well as record classes. Override methods, including that of the Object class. Implement polymorphism and differentiate between object type and reference type. Perform reference type casting, identify object types using the instanceof operator, and pattern matching with the instanceof operator and the switch construct.
Create and use interfaces, identify functional interfaces, and utilize private, static, and default interface methods.
Create and use enum types with fields, methods, and constructors.
Handling Exceptions
Handle exceptions using try/catch/finally, try-with-resources, and multi-catch blocks, including custom exceptions.
Working with Arrays and Collections
Create arrays, List, Set, Map and Deque collections, and add, remove, update, retrieve, and sort their elements.
Working with Streams and Lambda Expressions
Use Java object and primitive Streams, including lambda expressions implementing functional interfaces, to create, filter, transform, process, and sort data.
Perform decomposition, concatenation, reduction, grouping, and partitioning on sequential and parallel streams.
Packaging and Deploying Java Code
Define modules and expose module content, including that by reflection, and declare module dependencies, define services, providers, and consumers.
Compile Java code, create modular and non-modular jars, runtime images, and implement migration to modules using unnamed and automatic modules.
Managing Concurrent Code Execution
Create both platform and virtual threads. Use both Runnable and Callable objects, manage the thread lifecycle, and use different Executor services and concurrent API to run tasks.
Develop thread-safe code, using locking mechanisms and concurrent API.
Process Java collections concurrently and utilize parallel streams.
Using Java I/O API
Read and write console and file data using I/O streams.
Serialize and deserialize Java objects.
Construct, traverse, create, read, and write Path objects and their properties using the java.nio.file API.
Implementing Localization
Implement localization using locales and resource bundles. Parse and format messages, dates, times, and numbers, including currency and percentage values.
Who this course is for:
- Java developers preparing for Java SE 21 Developer Professional Exam 1Z0-830
- Anyone who want to become a certified Java Developer with Java 21
- Experienced Java Developers who want to certify for Java SE 11 Edition
Instructor
Our aim is to provide quality practice tests for online certification exams which can help them to build speed and accuracy required to crack these certification in first attempt and enhance their profile for career growth.
At the moment we are specialized in following certification
1. Java certification like 1Z0-819, 1Z0-829, Java Foundations, Java EE developer certification
2. Spring Professional certification
3. Cloud Certifications like AWS Cloud Practitioner, Azure Fundamentals etc