QuickPerf Documentation

When writing JUnit 4 tests for Spring 5 applications, use SpringRunnerWithQuickPerfFeatures as your test runner to enable QuickPerf performance monitoring features alongside the Spring TestContext Framework. This runner combines the capabilities of SpringJUnit4ClassRunner with QuickPerfJUnitRunner.

@RunWith(SpringRunnerWithQuickPerfFeatures.class)
@ContextConfiguration(classes = MyConfig.class)
public class MySpringTest {
    // Your performance-monitored Spring tests
}

QuickPerf provides annotations to assert the number of SQL statements executed during a test. This is particularly useful for detecting N+1 select issues in Hibernate or Spring Data JPA.

Example: Use @ExpectSelect(n) to assert that exactly n select statements are executed.

QuickPerf automatically detects Hibernate and Spring Data JPA and provides actionable suggestions (e.g., using JOIN FETCH or @EntityGraph) when assertions fail.

    @ExpectSelect(1)
    @Test
    public void should_find_all_players() {
     ...
    }

You can monitor JVM performance metrics by applying annotations to your test methods. For example, to measure heap allocation and assert a specific heap size limit, use @MeasureHeapAllocation and @HeapSize.

Supported test frameworks include JUnit 4, JUnit 5, and TestNG.

    @MeasureHeapAllocation
    @HeapSize(value = 1, unit = AllocationUnit.GIGA_BYTE)
    @Test
    public void execute_batch() {
        ...
    }

When troubleshooting QuickPerf configuration or execution order, you can view debug information in the standard output. The displayQuickPerfDebugInfos method outputs:

1. JVM Options: A list of the JVM options used during execution.
2. Recorder Execution Order: The priority and class names of recorders executed before and after test methods, determined by the QuickPerfConfigLoader implementations found via ServiceLoader.

This is useful for verifying if your custom recorders are being loaded in the expected priority order.

// Note: ConsoleReporter is package-private in the source, 
// but its methods are used by the framework to output debug info.
consoleReporter.displayQuickPerfDebugInfos(jvmOptions);

The displayQuickPerfAnnotations method outputs the specific QuickPerf annotations applied to a test or class to the console.

It provides:

• A comma-separated list of the applied annotations (formatted via AnnotationFormatter).
• The canonical name of the class that specifies global annotations (if any are configured via SpecifiableGlobalAnnotations).

Note that the DisplayAppliedAnnotations annotation itself is filtered out of the output to avoid redundancy.

// This method is called by the framework to report which 
// annotations are currently active in the test context.
consoleReporter.displayQuickPerfAnnotations(perfAnnotations);