Table of contents

1. Understanding the Basics of JUnit5
2. Profiling the Problem: Identifying Performance Issues in Unit Testing
3. Techniques for Speeding up JUnit5 Unit Tests
4. Optimizing Execution Time in JUnit5: Practical Approaches
5. Integration Test Setup: Best Practices with JUnit5
6. Results: Evaluating the Impact of Optimization on Test Performance
7. Strategies for Managing Workloads and Balancing Deadlines in Unit Testing with JUnit5
8. Addressing Common Challenges in JUnit5 Unit Testing Automation

Introduction

JUnit5, the latest version of the popular unit testing framework for Java, introduces a range of new features and improvements that can significantly enhance the efficiency and performance of unit tests. With its redesigned architecture and increased flexibility, JUnit5 offers developers the ability to create dynamic tests at runtime, perform parameterized testing with varying input values, and support for Java 8 and later versions. Additionally, JUnit5 provides seamless integration with Kotlin, making it a versatile choice for developers. In this article, we will explore the basics of JUnit5, its standout features, compatibility with contemporary Java development practices, and its support for Kotlin. We will also discuss practical approaches and techniques for speeding up JUnit5 unit tests, optimizing execution time, and managing workloads and deadlines. By leveraging the power of JUnit5, developers can improve the speed, reliability, and efficiency of their unit tests, ultimately enhancing the overall software development process

1. Understanding the Basics of JUnit5

The Java unit testing landscape has significantly evolved with the introduction of JUnit5, which offers a host of enhancements and new features that distinguish it from its predecessor, JUnit4. With a redesigned architecture, JUnit5 offers increased flexibility and customization, making it more adaptable to diverse development requirements.

One of the standout features of JUnit5 is dynamic testing, which allows tests to be created at runtime, thereby introducing a new level of flexibility to the testing process. Furthermore, JUnit5 introduces parameterized tests, enabling multiple executions of a test case with varying input values.

This is particularly beneficial when testing the same logic with different data sets.

In terms of compatibility, JUnit5 supports Java 8 and later versions. This alignment with contemporary Java development practices ensures JUnit5's compatibility with the latest features and functionalities offered by modern Java versions, making it even more appealing for developers.

JUnit5 boasts a comprehensive feature set, ranging from basic setup and writing tests to advanced features like lifecycle methods, parameterized tests with various sources such as ValueSource, CsvSource, CsvFileSource, and MethodSource, test run order, assumptions, disabling tests, repeating tests, tags for test selection, assertions, use of Hamcrest for assertions, running tests, use of Test Watcher, timeouts, and nested tests.

For developers considering migrating from JUnit 4 to JUnit 5, the framework provides a smooth transition path, offering guidance and support during the migration process.

Interestingly, JUnit5 also extends its support to Kotlin, making it a versatile choice for developers working with either Java or Kotlin. The framework heavily employs annotations, with several new ones introduced to enhance the testing process.

While JUnit5 is indeed a robust framework with a multitude of features, it's important to be mindful that some of these features are still in the experimental stage and may exhibit issues. Developers are encouraged to provide feedback on these experimental features to aid in their improvement.

In the realm of test automation, JUnit5 is not merely a new version of a popular unit testing framework; it represents a significant leap forward, introducing a range of new features and improvements. With the addition of Machinet, a platform that provides detailed guides for setting up JUnit5, it becomes even more potent. For instance, Machinet can help you integrate JUnit5 into your projects, providing instructions on topics like adding the JUnit5 dependency to your project, configuring test suites, writing and running unit tests, and reporting test results.

One of the key features of JUnit5 that Machinet can assist you with is parameterized testing. By using the built-in parameterized test support provided by JUnit5, you can run the same test with different sets of parameters. Here's an example of how you can perform parameterized testing with JUnit5 and Machinet:

```javaimport org.junit.jupiter.params.ParameterizedTest;import org.junit.jupiter.params.provider.ValueSource;

public class MyParameterizedTest {

@ParameterizedTest
@ValueSource(strings = {"param1", "param2", "param3"})
public void testWithParameters(String parameter) {
// Perform your test using the parameter
}


}``In this example, thetestWithParametersmethod is executed three times, once for each value in the@ValueSourceannotation. You can replace the@ValueSourceannotation with other argument providers like@CsvSourceor@MethodSource` to provide different sets of parameters for your tests.

JUnit5, along with Machinet, also offers features like test interfaces and test templates, which allow you to create reusable and customizable test code. Furthermore, the extension model in JUnit5 enables you to write custom extensions that can be applied to individual tests or test classes, enhancing your test capabilities.

In summary, JUnit5, when used in conjunction with platforms like Machinet, offers a comprehensive and flexible testing framework that can cater to a wide array of development needs

2. Profiling the Problem: Identifying Performance Issues in Unit Testing

Addressing performance bottlenecks in unit testing is pivotal in maintaining the speed and quality of software development. Various factors, such as inefficient test design, high resource consumption, and incorrect use of testing frameworks, can contribute to these performance issues. Profiling tools can be a great asset in this scenario, as they can help monitor the execution time of tests and identify potential bottlenecks. These tools offer detailed insights into the performance of tests, assisting developers in recognizing areas that need enhancement.

In the sphere of game development, performance optimization plays a key role in delivering immersive gaming experiences. Profiling and optimizing game performance can not only enrich the user experience but also broaden the player base, thereby improving the chances of success. A practical strategy in this context is to set a frame budget to ensure consistent experiences for players. However, measuring frame rate in frames per second (fps) may not provide the most precise approach for delivering consistent experiences. Instead, frame time in milliseconds is a more accurate metric for benchmarking game speed.

Thermal control is another significant consideration, especially for optimizing mobile games to avoid thermal throttling. Memory access operations can considerably impact performance on mobile devices. Therefore, establishing hardware tiers and conducting benchmarking for different platforms to optimize performance accordingly is advisable. Profiling early and frequently in the development lifecycle is key to identifying and addressing performance issues.

In Unity games, different threads, such as the main thread, render thread, and worker threads, can become performance bottlenecks. Investigating and optimizing specific areas, such as physics, monobehaviour scripts, and draw call batching, can significantly improve performance. GPU-bound scenarios can be caused by factors such as post-processing effects, fragment shaders, and overdraw. In these cases, using a GPU profiler can help identify and address GPU bottlenecks.

The Unity engine offers a comprehensive suite of products and services for game development, including tools for game backend, multiplayer engagement, analytics, growth, monetization, user acquisition, device management, and publishing platforms. Unity also supports multiplatform development for mobile, desktop, consoles, and VR, and offers a host of resources, including downloads, beta programs, releases, developer tools, documentation, technical FAQs, news, case studies, and product roadmaps.

In light of these considerations, identifying performance issues in unit testing is a complex task that requires a deep understanding of the testing process and the tools used. Profiling tools can be used to monitor the execution time of tests and identify bottlenecks, thereby helping developers identify areas for improvement. With the right tools and strategies, developers can optimize their unit tests' performance, thereby speeding up the development process and delivering high-quality software products."

To optimize unit tests for better performance,

Learn how Machinet can help you optimize your unit tests for better performance.

it is crucial to follow certain best practices. Reducing the number of dependencies and external resources that the unit tests rely on can improve performance. By minimizing these dependencies, the tests can run faster and more efficiently. Mocking frameworks can be used to simulate the behavior of external dependencies, rather than relying on the actual implementations. This helps isolate the unit under test and speeds up the execution of the tests. Organizing the tests into smaller, focused test cases rather than having a single large test case allows for better isolation and easier identification of performance bottlenecks. Regularly reviewing and refactoring the unit tests ensures that they remain efficient and effective.

Identifying and fixing performance bottlenecks in unit tests is crucial for maintaining the efficiency and reliability of software development processes. Profiling tools can provide insights into the execution time of different parts of the unit tests and help pinpoint areas that may be causing delays. Analyzing the profiling data, developers can identify specific code segments or operations that are consuming excessive time and resources. Once the bottlenecks have been identified, developers can then proceed to fix them by rewriting or refactoring the code to make it more efficient, eliminating unnecessary operations, or finding alternative approaches to achieve the same results in a more optimized manner. Techniques such as parallelization or caching can be used to improve the performance of the unit tests.

Efficient resource usage in unit testing can be achieved by designing the unit tests in such a way that they only test the specific functionality or behavior that needs to be validated. Using test doubles or mocks for external dependencies instead of relying on actual resources such as databases or web services allows for faster and more isolated testing. Prioritizing and focusing on testing critical and high-risk areas of the code can allocate resources more effectively and ensure that the most critical functionalities are thoroughly tested. Properly cleaning up any resources that are used during the unit tests, such as closing database connections, releasing file handles, or clearing any temporary data created during the tests, prevents resource leaks and ensures efficient execution of tests.

Proper test design plays a crucial role in improving unit test execution time. Ensuring that unit tests are focused and only test a specific functionality or component helps in isolating the code being tested and reduces the overall execution time. Using test doubles such as mocks or stubs for external dependencies allows testing the code in isolation without the need for the actual dependencies, significantly speeding up the execution time. Prioritizing and optimizing the order in which unit tests are executed helps identify failures or issues early on and avoid unnecessary execution of subsequent tests. Parallel test execution can help in utilizing available system resources and further reduce the overall execution time.

When it comes to optimizing testing frameworks for better performance, several strategies can be implemented. Identifying and eliminating any unnecessary or redundant tests reduces the overall number of tests, making the framework execute more quickly and efficiently. Optimizing the test environment by using parallel testing significantly improves performance. This involves running multiple tests simultaneously, taking advantage of multi-core processors and distributed systems. Prioritizing tests based on their impact and criticality, running the most important tests first to quickly identify any critical issues is another strategy. Finally, optimizing the test data contributes to better performance. By using realistic and representative data, the tests can provide more accurate results without unnecessary overhead.

When working on large projects, it's important to consider strategies for improving unit test performance. By optimizing the unit tests, developers can ensure that the tests run efficiently and do not significantly slow down the development process. Identifying and eliminating unnecessary dependencies, prioritizing the execution of unit tests based on their importance and impact, and employing techniques such as test data management and test data generation can streamline the execution of unit tests. Optimizing the setup and teardown processes of the unit tests can also contribute to improved performance. By minimizing the time and resources required for initialization and cleanup,

Discover how Machinet can help you minimize the time and resources required for initialization and cleanup in your unit tests.

developers can reduce the overall execution time of the tests

3. Techniques for Speeding up JUnit5 Unit Tests

Enhancing the speed of JUnit5 unit tests can be achieved through a combination of strategies, including examining smaller units of code, employing mocking frameworks like Mockito, and leveraging JUnit5's parallel test execution feature.

Focusing on smaller units of code during testing, as opposed to extensive functionality sections, can result in more rapid test execution. This approach aligns with the principle of maintaining quick builds, which can have a positive impact on team productivity. To this end, one can use the @Nested annotation in JUnit5 to group related tests together, allowing for the isolated testing of smaller code units. Moreover, the @BeforeEach and @AfterEach annotations can be utilized to set up and tear down necessary test fixtures for each test, ensuring their independence and reliability.

Mocking frameworks, such as Mockito, offer a significant advantage in test execution time. Mockito, a widely-used Java mocking framework, allows the creation of mock objects, stub method calls, and verification of interactions. It helps simulate the behavior of dependencies in unit tests, which can improve the speed of tests by reducing the necessity for complex setup code. Mockito's @Mock annotation and Mockito.mock() method can be used to create mock objects, with methods such as when() and thenReturn() defining the behavior of these objects.

JUnit5's support for parallel test execution is a valuable tool for running multiple tests simultaneously, thereby reducing the overall test execution time. Using the @Execution annotation and specifying the CONCURRENT mode allows JUnit5 to run tests in parallel. The number of threads or processes used for parallel execution can be configured with the junit.jupiter.execution.parallel.config.strategy system property. This strategy is particularly effective when dealing with multiple pull requests and commits, where slow builds can drain productivity.

Differentiating between proper unit tests and scenario-driven integration tests is crucial to ensure tests are focused and efficient, avoiding the slow and imperfect middle ground. This practice aligns with the advice of separating unit and integration tests, which can result in faster compile times and a quicker failure response in the continuous integration process.

Lastly, keeping build tools up to date and investing in faster CI machines are other efficacious strategies for improving build speeds. By understanding the reasons behind slow builds and taking deliberate steps to enhance them, software engineers can significantly improve their productivity and the quality of their output

4. Optimizing Execution Time in JUnit5: Practical Approaches

JUnit5 offers a suite of strategies to enhance the efficiency of your unit tests and significantly reduce their execution time. For instance, the @TestInstance annotation can be leveraged to reuse test instances, thereby alleviating the overhead of creating new instances for each test method.

To manage the execution order of tests, particularly when some tests are known to require a longer execution time, JUnit5 provides different execution orders such as Random, DisplayName, and MethodOrder. This can be achieved by utilizing the @TestMethodOrder annotation.

Furthermore, reducing external dependencies in your tests can considerably cut down the execution time. Instead of relying on external resources like databases or network calls, consider using in-memory databases or mocking frameworks to simulate these dependencies.

Another compelling feature of JUnit5 that can significantly improve test execution time is the parallel execution of tests. This feature, enabled by the @Execution annotation, allows for the concurrent execution of tests, drastically reducing the total execution time.

However, when parallelizing tests, it is crucial to manage resources properly after execution. For instance, closing database connections, releasing file handles, or stopping background processes after tests can prevent resource leaks and slower test execution over time.

Additionally, focusing on minimizing the initialization time of the JVM and Spring context is essential. Running tests with JUnit configuration instead of the default Gradle configuration can enhance JVM initialization time. Reusing the spring boot context between test classes can also reduce startup time.

Annotations such as @MockBean, @SpyBean, and @DirtiesContext should be used judiciously to avoid unnecessary context recreation. Creating a parent class with shared mock beans can ensure the consistent usage of the custom context in test classes.

To improve test readability, employing assertion libraries like AssertJ is recommended. AssertJ's soft assertions allow the collection of multiple assertion failures during the execution of a test and report them all at once at the end, improving the overall performance of your tests.

Lastly, creating custom run/debug configurations and tags for more efficient test execution is beneficial. Profiling tests can also be used to identify performance bottlenecks.

As a testament to the effectiveness of these strategies, a Kotlin Spring Boot Gradle project with around 1500 tests initially required 13 minutes per run. However, after implementing these optimizations, the runtime was reduced to 5 minutes. This underscores the potential of these techniques in enhancing test performance

5. Integration Test Setup: Best Practices with JUnit5

JUnit5 paves the way for best practices in integration tests. Notably, the @SpringBootTest annotation in Spring Boot applications is a powerful tool for initiating an application context designed for integration testing. To effectively use this annotation, one needs to annotate the test class with @SpringBootTest. This denotes the test as an integration test for a Spring Boot application. Additional configurations can be added using the @SpringBootTest annotation. For instance, the classes attribute can be used to define the specific configuration classes needed for the test. The @Autowired annotation is used to inject any dependencies required for the test. After setting up the test methods using the appropriate test frameworks like JUnit or TestNG, the integration tests can be run using your preferred test runner such as Maven or Gradle.

Furthermore, test containers are an indispensable tool for testing code that interacts with external resources like databases or message brokers. These containers provide a lightweight, disposable environment for operating these resources, ensuring that tests are isolated and repeatable. Developers can spin up containers during test execution, enabling testing against real instances of these external resources. This provides a more accurate representation of the production environment, invaluable in scenarios where mocking or stubbing the external resources is not feasible or desirable.

Test containers also offer an easy way to manage the lifecycle of your test containers. Developers can start and stop them as needed during test execution, ensuring each test is executed in an isolated, controlled environment, preventing interference between different test cases. By encapsulating test dependencies in Docker containers and managing their lifecycle during test execution, test containers enable developers to create isolated and repeatable integration tests.

Another key feature in JUnit5 is the @Nested annotation. This annotation allows tests to be organized into hierarchies, enhancing the manageability of test suites. The @Nested annotation allows the creation of nested test classes within a test class, where each nested class represents a different scenario or context for testing. This is particularly useful in managing complex integration tests that require multiple setups and configurations.

The blog post by Petri Kainulainen, published on December 13, 2021, offers additional insights into setting up a Gradle project for compiling and running unit tests with JUnit5. The project's necessary dependencies are sourced through Gradle and the Maven Central Repository. The post also provides a guide on creating a simple unit test class and instructions for running unit tests with Gradle.

The blog post further delves into writing parameterized tests with JUnit5. It elucidates the process of obtaining required dependencies, demonstrates writing the first parameterized test with the @ParameterizedTest and @ValueSource annotations, and shows how to customize the display name of each method invocation in a parameterized test. It explores different argument sources that can be used in JUnit5 parameterized tests, such as @EnumSource, @CsvSource, @CsvFileSource, and custom argument providers, providing examples of passing enum values, multiple arguments, and complex objects to parameterized tests.

Finally, it's worth noting that the JUnit Jupiter version 5.8.2 is added as a dependency in the build.gradle file. The command "gradle clean test" is used to run the unit tests with Gradle. While Gradle has built-in support for JUnit5, it must be enabled manually

6. Results: Evaluating the Impact of Optimization on Test Performance

Assessing the impact of optimization strategies on unit test performance necessitates a detailed examination of test execution times before and after applying the optimization techniques. Profiling tools can assist in this process by providing comprehensive statistics on the duration of individual tests.

The interpretation of these results can offer crucial insights into the effectiveness of the optimization strategies used. However, it's important to remember that while optimization can significantly improve unit test performance, it should not compromise the quality or depth of the tests. The primary goal of unit testing is to verify the accuracy of the code, which should always remain the primary focus.

In today's digital world, the speed of experimentation and site performance is critical. Page performance directly impacts business outcomes. Slow sites can have negative effects, while improvements in speed can yield substantial benefits.

Companies like Optimizely understand this, partnering with leading CDN providers and implementing CDN load balancing for efficient content delivery. They've also conducted experiments to measure the impact of longer page load times on business outcomes. Optimizely's initiatives include launching custom snippets to reduce page load time, adding batching and customizable timing to event tracking to reduce network calls, and developing an article detailing best practices for enhancing site performance.

For profiling test execution time, tools like JUnitPerf, a JUnit extension, can be valuable. It provides annotations and assertions for defining performance tests and analyzing their execution time. Other tools like JProfiler, VisualVM, and YourKit can also offer comprehensive performance analysis, including CPU and memory usage, thread contention, and more.

Optimization techniques for improving test performance can include prioritizing test cases, efficient test data management, configuring the test environment to resemble the production environment, parallel test execution, test automation, test case optimization, load testing, test environment monitoring, test suite optimization, and test reporting and analysis.

Maintaining code quality during optimization is crucial. Regular code reviews, comprehensive unit tests, proper documentation of changes made during optimization, and using version control systems can help ensure code quality.

There are numerous online platforms and websites offering resources to learn about optimizing test performance. These resources include articles, blog posts, tutorials, and videos focusing on best practices and techniques for improving the performance of tests. Online communities and forums where software testing professionals share their experiences and insights can also be a valuable resource

7. Strategies for Managing Workloads and Balancing Deadlines in Unit Testing with JUnit5

Unit testing with JUnit5 presents an opportunity to manage workload and balance timelines effectively through a combination of strategies and techniques.

A fundamental strategy is to prioritize tests based on their relevance and complexity. This involves running the most critical and intricate tests at the start of the development process. Early execution of these tests can identify potential issues at the earliest possible stage, paving the way for immediate resolution and reducing the impact on the overall project timeline.

Incorporating continuous integration tools such as Jenkins into your workflow is another key strategy. Jenkins' built-in support for JUnit testing allows you to define a job that regularly runs your JUnit tests or triggers them based on specific events. This tool can fetch the latest code from your version control system, build the project, and then execute the JUnit tests using the JUnit5 framework. By integrating Jenkins with JUnit5, the execution of your tests can be easily automated, providing continuous feedback on the health of your codebase.

Adopting a test-driven development (TDD) approach is another effective strategy. In TDD, tests are written before the code is developed, promoting better code quality by forcing developers to think about the desired behavior of the code before writing it. This approach not only ensures that all code is tested but also reduces the likelihood of bugs, thus minimizing the need for rework and further enhancing efficiency.

JUnit 5.4, the latest version of JUnit, simplifies the process of using JUnit by including a single junit-jupiter dependency. This version introduces the use of temporary directories for testing, allowing for easy creation and cleanup of temporary files. Parameterized tests in JUnit 5.4 now support null and empty values as input parameters. The display name of test methods can be generated dynamically based on the nested class or method name. JUnit 5.4 introduces the ability to order test methods using the new testmethodorder annotation.

Testing is crucial in ensuring the reliability and stability of applications. AssertJ and JUnit 5 provide a robust and user-friendly framework for testing applications. AssertJ's fluent API allows for readable and natural assertions in tests. JUnit 5's lifecycle and extension model seamlessly integrate with AssertJ, creating a powerful tool for software testing.

To balance workloads in JUnit 5 unit testing, it is recommended to leverage parallel execution, distributed testing environments, and prioritization techniques. These strategies optimize the test execution time and improve overall efficiency. Critical or time-sensitive test cases can be identified and tagged, giving them higher priority during execution, ensuring that they are completed first.

When it comes to managing deadlines in JUnit 5 unit testing, best practices such as setting a timeout for each individual test case using the @Timeout annotation and using the assertTimeout method to enforce a timeout for a specific block of code within a test case can be adopted. Prioritizing and organizing test cases based on their expected execution time is also crucial.

Efficiency in JUnit5 unit testing can be improved by using Parameterized Tests, Test Suites, Test Fixtures, wise use of Assertions, defining Test Dependencies, and enabling Parallel Execution. These techniques, when implemented correctly, significantly enhance the efficiency of the software development process and the reliability of the resulting software

8. Addressing Common Challenges in JUnit5 Unit Testing Automation

Addressing issues in JUnit5 unit testing automation can be a complex task, with various challenges to tackle. One of the most prevalent difficulties is the occurrence of flaky tests, which are characterized by their inconsistent results, passing or failing without any changes in code. The unpredictability of these tests can be attributed to multiple factors including non-deterministic code behavior and application performance issues.

In the face of such issues, several tools have emerged to help detect flaky tests. For instance, the JUnit Pioneer project offers a plugin called "JUnit Pioneer Flaky Test Detector" that works with JUnit 5. This plugin examines test results and generates a report indicating which tests are likely to be flaky. There is also the Flaky Test Detector plugin for IntelliJ IDEA, designed specifically for JUnit 5 projects, which highlights inconsistent results and offers suggestions for further investigation. Additionally, the Build Failure Analyzer plugin for Jenkins can be used to identify patterns that indicate flakiness, generate reports, and notify the appropriate team members when a flaky test is detected.

The process of handling flaky tests can be divided into three main stages: reproduction, diagnosis, and fixing. This involves running the test suite multiple times on a CI service to observe the inconsistent results, examining failure messages, test code, and application code to identify the root causes, and finally addressing the flaky test through applying a fix and devising a test to confirm that the bugfix is effective.

Another common challenge in JUnit5 unit testing automation is managing test data, particularly for tests that interact with databases. Tools like DBUnit or Mockito can be employed to help manage test data in your database during test execution, ensuring that tests are isolated, independent, and that the test data is consistent and predictable.

The migration from JUnit4 to JUnit5, although beneficial due to the advanced features and syntax of JUnit5, can present its own challenges. However, JUnit5 provides a compatibility layer, known as JUnit Vintage, which allows for the execution of JUnit4 tests in a JUnit5 environment. This feature considerably simplifies the migration process and allows developers to leverage the advantages of JUnit5 without having to completely rewrite their JUnit4 tests.

In essence, while JUnit5 unit testing automation does present several challenges, various strategies and techniques are available to tackle these issues effectively. By understanding and addressing these challenges, developers can significantly enhance the reliability and efficiency of their unit testing processes

Conclusion

In conclusion, JUnit5 is a powerful unit testing framework for Java that offers a range of new features and improvements. Its dynamic testing capabilities allow tests to be created at runtime, providing flexibility in the testing process. The introduction of parameterized tests enables multiple executions of a test case with varying input values, enhancing test coverage. JUnit5's compatibility with Java 8 and later versions ensures it can leverage the latest features and functionalities. The seamless integration with Kotlin makes it a versatile choice for developers working with either Java or Kotlin. By adopting JUnit5 and leveraging its features, developers can improve the efficiency and reliability of their unit tests.

The ideas discussed in this article have broader significance for software development as a whole. Efficient and reliable unit testing is crucial for building high-quality software products. By using JUnit5 and implementing the optimization techniques outlined in this article, developers can significantly improve the speed and performance of their unit tests. This leads to faster development cycles, quicker feedback loops, and ultimately, higher productivity. Additionally, by incorporating JUnit5 into their testing process, developers can ensure compatibility with modern Java development practices and take advantage of its seamless integration with Kotlin.

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