# 2026-02-02 This release introduces support for Java 25 projects and enhances the CLI to detect when generated tests fail project style checks, such as Apache Checkstyle. *** ## Language Support * **Java 25 Support:** Diffblue Cover now supports writing tests for Java 25 projects. ## CLI & Integration * **Style Check Detection:** Cover now detects when generated tests fail a project's style checks (e.g., Apache Checkstyle) during validation. It reports a new `E171` warning with guidance on resolving formatting incompatibilities. *** ## Enhancements * Diffblue Cover now supports writing tests for projects using Java 25 language features. \[Ref: TG-24170] * CLI: Diffblue Cover now detects when generated tests fail a project's style checks (e.g., Apache Checkstyle) during validation and reports a new `E171` warning with guidance on resolving formatting incompatibilities. \[Ref: TG-24169] ## Known Issues * Plugin: Diffblue Cover incorrectly displays a menu option to write tests for existing test files. \[Ref: TG-17163] * Using JDKs other than the supported Open JDK and Oracle JDK may produce unexpected results due to implementation differences. \[Ref: TG-19345] * Cover may encounter an `F009` (Internal error) caused by a `ClassCircularityError` involving `org/mockito/configuration/MockitoConfiguration` when writing tests with Mockito 5. The recommended workaround is to downgrade to Mockito 4.x. \[Ref: TG-19610] * Reports: The total line count metric in Reports only includes Java code. Kotlin code is not included. \[Ref: TG-22088] * Reports: Total lines of code metric can incorrectly count a multi-line comment at the end of a line of code, resulting in fewer than expected lines counted. \[Ref: TG-22089] * Reports: Following an upgrade, the 'Total Lines of Code' card may show 0 until a new reports bundle has been uploaded. \[Ref: TG-22094] * Cover may write more simplistic tests with less meaningful assertions when Spring Boot dependency injection is disabled. \[Ref: TG-22102] * In some circumstances, Cover will still write Spring Boot tests when Spring Boot dependency injection is disabled. \[Ref: TG-22103] * Cover may write failing TestNG tests when Spring Boot dependency injection is disabled. \[Ref: TG-22107] * Plugin: On some displays, the Test Review subsection title 'Tests for review' is malformed. \[Ref: TG-22805] * When test formatting settings are changed, the Test Review feature may incorrectly remove the `@ManagedByDiffblue` annotation from tests, particularly in cases involving static import formatting changes. \[Ref: TG-23750] * Plugin: Using the Test Review feature may create tests that have incompatible dependency injection systems. \[Ref: TG-23935] * CLI: In rare circumstances, Cover may remove existing tests when using merge mode (`--merge`). The recommended workaround is to use the `@WriteTestsTo` annotation to specify a separate test class. \[Ref: TG-24166] * Plugin: When writing tests for a project that targets a JDK version newer than IntelliJ's runtime JDK (e.g., Java 25 with IntelliJ's bundled Java 21), generated tests may not match the project's non-default formatting style and will instead use default IntelliJ formatting. \[Ref: TG-24168] --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://cover-docs-preview.diffblue.com/updates-and-upgrades/release-archive/2026-02-02.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.