neotest-java

Neotest adapter for Java, using JUnit.

• ✅ Maven & Gradle - Full support for both build systems (Groovy & Kotlin DSL)
• ✅ Multi-module projects - Automatic detection and per-module test execution
• ✅ JUnit 5 (Jupiter) - Support for @Test, @ParameterizedTest, @TestFactory, nested tests
• ✅ JUnit Platform 1.10.x & 6.x - Compatible with both legacy and latest versions
• ✅ Spring Framework - Auto-loads application.yml, application-test.yml, and .properties files
• ✅ Debugging with nvim-dap - Full integration with breakpoints, JDWP, and DAP REPL output
• ✅ Incremental compilation - Smart compilation of only changed files via nvim-jdtls
• ✅ Automatic classpath management - Retrieves runtime and test classpaths from LSP
• ✅ JUnit JAR management - Automatic installation, version detection, and upgrade prompts
• ✅ Health check - Comprehensive diagnostics with :checkhealth neotest-java

Check ROADMAP.md to see what's coming!

• Neovim 0.10.4+
• nvim-treesitter with Java parser: :TSInstall java
• nvim-jdtls - Language server for Java
• nvim-dap - For debugging support (optional)

return {
  {
    "rcasia/neotest-java",
    ft = "java",
    dependencies = {
      "mfussenegger/nvim-jdtls",
      "mfussenegger/nvim-dap", -- for debugging (optional)
      "rcarriga/nvim-dap-ui", -- recommended
      "theHamsta/nvim-dap-virtual-text", -- recommended
    },
  },
  {
    "nvim-neotest/neotest",
    dependencies = {
      "nvim-neotest/nvim-nio",
      "nvim-lua/plenary.nvim",
      "antoinemadec/FixCursorHold.nvim",
      "nvim-treesitter/nvim-treesitter",
    },
    config = function()
      require("neotest").setup({
        adapters = {
          require("neotest-java")({
            -- Optional configuration here
          }),
        },
      })
    end,
  },
}

After setting up the plugin, run:

:NeotestJava setup

This will automatically download and verify the JUnit Platform Console Standalone JAR from Maven Central with SHA-256 checksum verification.

All configuration options are optional. Pass them to require("neotest-java")({}):

require("neotest").setup({
  adapters = {
    require("neotest-java")({
      junit_jar = nil, -- default: auto-detected
      jvm_args = { "-Xmx512m" }, -- custom JVM arguments
      incremental_build = true, -- recompile only changed files
      disable_update_notifications = false, -- show JUnit update prompts
      test_classname_patterns = { "^.*Tests?$", "^.*IT$", "^.*Spec$" },
    }),
  },
})

If you're running Spring tests that use reflection (e.g., @MockBean, @WebMvcTest) and encounter errors like:

java.lang.IllegalArgumentException: Name for argument of type [int] not specified,
and parameter name information not available via reflection.
Ensure that the compiler uses the '-parameters' flag.

Solution: Configure the JDTLS compiler to preserve parameter names in bytecode by adding the following to your project's .settings/org.eclipse.jdt.core.prefs file:

org.eclipse.jdt.core.compiler.codegen.methodParameters=generate

If the .settings directory doesn't exist, create it in your project root:

mkdir -p .settings
echo "org.eclipse.jdt.core.compiler.codegen.methodParameters=generate" > .settings/org.eclipse.jdt.core.prefs

After adding this setting, restart your LSP server (:LspRestart) and run your tests again.

Contributions are welcome! Please feel free to:

• 🐛 Report bugs and issues
• 💡 Suggest new features or improvements
• 🔧 Submit pull requests

See CONTRIBUTING.md for guidelines.

The project includes both unit tests and end-to-end (E2E) tests:

# Run unit tests
make test

# Run E2E tests (requires Java and JAVA_HOME)
make test-e2e

# Run all tests
make test && make test-e2e

E2E Test Requirements:

• Java JDK (11 or higher)
• JAVA_HOME environment variable set
• Maven wrapper is included in the test fixture

See tests/e2e/README.md for detailed E2E test documentation.

Thanks to all contributors who have helped improve this project!