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Write a Java test as a method marked with JUnit Jupiter’s @Test, use an assertion to check the expected behavior, and run it through the build tool already configured in your project. With Maven, the usual command is mvn test; with Gradle, it is ./gradlew test. The test must be in the project’s test source set, and the build needs both JUnit’s API and a runtime engine and integration that can discover and execute the test.
Write a basic JUnit test
A JUnit Jupiter test is an ordinary Java method marked with @Test. An assertion compares the expected result with the value produced by the code under test:
import static org.junit.jupiter.api.Assertions.assertEquals;
import org.junit.jupiter.api.Test;
class CalculatorTest {
@Test
void addsTwoNumbers() {
assertEquals(4, 2 + 2);
}
}Here, 4 is the expected value and 2 + 2 is the actual value. If they differ, the assertion fails and the build reports a failed test. This small example checks an expression; in an application, call the behavior you care about and assert its meaningful result. Choose a method name that makes the behavior clear, and keep each test understandable and independent where practical.
The imports show the JUnit Jupiter API. The annotation identifies the test method, while the static import lets the test call assertEquals directly. JUnit’s foundational annotation and assertion example is documented in its User Guide; its version is an old milestone, so use it for those basic concepts rather than copying historical dependency versions.
#1 Best Overall
- Read Before You Buy — No Video Output: These adapters support charging and USB 2.0 data transfer, but cannot transmit video signals. Except for standard USB webcams (which use USB data only), they are not compatible with HDMI/DisplayPort cables, video-capable USB-C hubs, or docking stations with video output.
- Convert USB-A Ports to USB-C: Designed to connect USB-C earphones, cables, flash drives, card readers, and other USB-C accessories to standard USB-A ports. Plug-and-play with no drivers or software required.
- Aluminum Alloy Housing: Built with a sturdy aluminum alloy shell that aids in heat dissipation and protects against daily wear and scratches. Designed to maintain a stable and secure connection.
- Compact & Travel-Friendly: The ultra-compact design allows the adapter to stay plugged into your device without blocking adjacent ports or adding bulk, reducing wear and tear on your original USB ports.
- 12-Month Warranty: Backed by a 12-month manufacturer warranty for peace of mind. Designed to meet strict quality control standards for reliable everyday performance.
Run tests with Maven
- Check the project configuration. Use the Maven setup already in the repository. Add JUnit as a test-scoped dependency and make sure the selected test engine is available at test runtime. The test API is needed to compile the imports and annotations; an engine is needed to execute Jupiter tests. See the Maven Surefire JUnit Platform documentation for configuration details.
- Put the test in the test source tree. Maven’s conventional location is
src/test/java, unless the project configures another source root. A package declaration and directory structure should match the project’s conventions. - Run the test lifecycle. From the project directory, run
mvn test. To select a class, documented Surefire usage supportsmvn -Dtest=CalculatorTest test. Selection and discovery can depend on the Surefire version and project configuration, so check those settings if a targeted run finds nothing. - Read the test result and reports. Distinguish failures, errors, skips, and tests not discovered. Successful compilation alone does not mean the tests executed.
JUnit 4 projects or migrations
If an existing project uses JUnit 4 while running tests through Surefire’s JUnit Platform setup, check whether the Vintage engine is configured. The current Surefire JUnit documentation identifies JUnit 4.12 as the minimum supported JUnit 4 version in that setup. Confirm the Surefire version and project configuration rather than assuming the requirement applies to every JUnit 4 arrangement. Surefire 3.6.0 changes JUnit Platform execution behavior, so verify the version actually used by the build. See Surefire’s JUnit documentation.
Run tests with Gradle
- Add test dependencies. In a Java project, add JUnit Jupiter to the test dependency configuration. The Gradle 9.8.0 testing guide shows
testImplementationfor Jupiter andtestRuntimeOnlyfor the JUnit Platform launcher. - Enable the JUnit Platform. Configure the Gradle
testtask to use JUnit Platform, for example in Groovy DSL:dependencies { testImplementation 'org.junit.jupiter:junit-jupiter:5.10.2' testRuntimeOnly 'org.junit.platform:junit-platform-launcher' } tasks.named('test') { useJUnitPlatform() }The dependency versions above are an illustrative configuration, not a version recommendation. Use versions compatible with the project’s dependency management and current JUnit and Gradle configuration. Gradle’s current testing chapter is the Gradle 9.8.0 Java testing guide.
Rank #2
Anker USB-C Hub, 5-in-1 USB Hub for Laptops, 4K HDMI Multiport Adapter- 5-in-1 USB-C Hub: Experience comprehensive connectivity featuring a Power Delivery input, two USB-A 2.0 ports, a USB-A 3.0 port, and an HDMI port. (Note: The USB-C power delivery input port is only for connecting an external wall charger to power your laptop and cannot power peripheral devices.)
- 90W Pass-Through Charging: Achieve optimal charging with 90W pass-through power to your laptop, supported by a total input of 100W, with the hub reserving 10W for operational efficiency. (Note: Wall charger not included.)
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- 4K HDMI Display: Enhance your visual experience with a hub capable of delivering 4K resolution at 30Hz in both mirror and extend modes. Please note that this hub is compatible with MacBook (macOS 12 and newer), Windows 10 and 11, ChromeOS, and laptops equipped with DP Alt Mode and Power Delivery. Note: This device is not compatible with Linux.
- What You Get: Anker USB-C Hub (5-in-1, 4K HDMI), welcome guide, 18-month warranty, and our friendly customer service.
- Use the test source set. The Java plugin provides a dedicated test source set, with its source files, classpath, and test task wired into the build. Put the test in the configured test source location; do not assume a custom project has retained defaults.
- Run the test task. If the project includes the Gradle wrapper, run
./gradlew teston macOS or Linux, orgradlew teston Windows. The wrapper helps run the Gradle version selected by the project. Review the task output and test report to see what ran and what failed.
Target a test in Gradle
Gradle supports test filtering. For example, a class can be selected from the command line with:
./gradlew test --tests 'CalculatorTest'Use the project’s fully qualified class or method pattern when needed, and check the configured filters if the task reports no matching tests. The Gradle guide covers filtering, logging, reports, detection, and troubleshooting.
Rank #3
- Sleek 7-in-1 USB-C Hub: Features an HDMI port, two USB-A 3.0 ports, and a USB-C data port, each providing 5Gbps transfer speeds. It also includes a USB-C PD input port for charging up to 100W and dual SD and TF card slots, all in a compact design.
- Flawless 4K@60Hz Video with HDMI: Delivers exceptional clarity and smoothness with its 4K@60Hz HDMI port, making it ideal for high-definition presentations and entertainment. (Note: Only the HDMI port supports video projection; the USB-C port is for data transfer only.)
- Double Up on Efficiency: The two USB-A 3.0 ports and a USB-C port support a fast 5Gbps data rate, significantly boosting your transfer speeds and improving productivity.
- Fast and Reliable 85W Charging: Offers high-capacity, speedy charging for laptops up to 85W, so you spend less time tethered to an outlet and more time being productive.
- What You Get: Anker USB-C Hub (7-in-1), welcome guide, 18-month warranty, and our friendly customer service.
Choose the build workflow your project uses
For an existing repository, follow its build system rather than adding a second one just to run tests. If both are options for a new project, make the decision based on the repository’s dependency setup, test filtering and reports, CI integration, and the team’s familiarity. The documented capabilities do not establish a universal performance or quality winner.
| Question | Maven | Gradle |
|---|---|---|
| Typical test source arrangement | src/test/java by convention; projects can configure another root. |
The Java plugin provides a dedicated test source set. |
| JUnit Platform setup | Configure a compatible Surefire setup and ensure a test engine is available at runtime. | Declare Jupiter test dependencies and configure the test task with useJUnitPlatform(). |
| Common test command | mvn test |
./gradlew test when the wrapper is present |
| Targeting and diagnosis | Surefire supports class selection with -Dtest=ClassName; consult the configured plugin version and generated reports. |
Use test filtering and task reports; consult configured filters and Gradle’s test output. |
Troubleshoot tests that will not run
- No tests found: Confirm the file is in the configured test source set, the class and method match discovery conventions, and no include, exclude, or command-line filter is excluding it. Maven documents default patterns and configurable discovery rules; Gradle documents test detection and filtering.
- JUnit imports or annotations do not compile: Make sure the JUnit API is a test compile dependency, and that the project resolved the dependency successfully.
- Tests compile but do not execute: Check that a compatible test engine is on the runtime classpath and that the build tool is configured to run the JUnit Platform. In Gradle, verify
useJUnitPlatform(); in Maven, inspect the Surefire and engine configuration. - JUnit 4 tests disappear after a platform migration: Check the Vintage engine and, for Surefire’s documented platform setup, the JUnit 4 version requirement. Also verify the Surefire version because platform execution behavior varies by version.
- The command line and IDE disagree: Compare the build configuration, JDK, and resolved dependencies used by each. IDE-specific behavior depends on the IDE and project setup; the build tool’s test task or lifecycle is the useful reference for confirming what the configured build discovers.
- A build passes but no test result is visible: Inspect test summaries and generated reports. Compilation is not evidence that tests were discovered or executed.
Or skip the browser setup
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Rank #4
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- Next-Level 10Gbps & 3A Charging: No more slow 480Mbps, this usb to usb c adapter has a transfer speed of up to 10Gbps, allowing you to do more transferring in less time. This usb adapter fits both USB A and USB C charger, supporting up to 3A fast charging
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- Broad Compatible: The usb c to usb adapter widely supports all USB C/ USB A devices like laptops, tablets, cellphones, car chargers, and phone chargers. Such as compatible with MacBook Pro/Air 2023/2022, Thunderbolt 4/3 Devices,Apple MagSafe Watch 9/8/7/SE/Ultra, iPad Pro 2022/2021, Samsung Galaxy S23/S20/S10, and iPhone 17/16/15 Pro. Plug and play
- Please Note: To reach 10Gbps speed, keep the cable under 3.3 ft. For USB A Male to USB C adapters, try flipping the USB C connector. USB C Male to USB A adapters support bidirectional 10Gbps transfer within 3.3 ft
curl -G "https://api.screenshotneo.com/v1/shot" -d access_key=YOUR_API_KEY --data-urlencode url=https://stripe.com -o shot.webpSee the ScreenshotNeo API documentation for request options. It can accept cookie or consent banners and remove more than 60 known consent platforms, newsletter popups, and chat widgets before capture; each of those steps can be turned off. Bot checks or CAPTCHAs, blank pages, timeouts, failed loads, and cache hits cost nothing, and responses identify the page verdict and billing status in headers. Its MCP server offers take_screenshot, get_page_info, and capture_pdf for AI agents using Claude, Cursor, or another MCP client. The free plan includes 1,000 screenshots a month with no card; paid plans start at $5 for 3,000 shots.
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Quick Recap
Best Value
- 5-in-1 Connectivity: Equipped with a 4K HDMI port, a 5 Gbps USB-C data port, two 5 Gbps USB-A ports, and a USB C 100W PD-IN port. Note: The USB C 100W PD-IN port supports only charging and does not support data transfer devices such as headphones or speakers.
- Powerful Pass-Through Charging: Supports up to 85W pass-through charging so you can power up your laptop while you use the hub. Note: Pass-through charging requires a charger (not included). Note: To achieve full power for iPad, we recommend using a 45W wall charger.
- Transfer Files in Seconds: Move files to and from your laptop at speeds of up to 5 Gbps via the USB-C and USB-A data ports. Note: The USB C 5Gbps Data port does not support video output.
- HD Display: Connect to the HDMI port to stream or mirror content to an external monitor in resolutions of up to 4K@30Hz. Note: The USB-C ports do not support video output.
- What You Get: Anker 332 USB-C Hub (5-in-1), welcome guide, our worry-free 18-month warranty, and friendly customer service.
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