Cucumber BDD in Java offers several key features that make it a popular choice for implementing BDD practices in software development:

1. Gherkin Language: Cucumber uses the Gherkin language, which is a plain-text, business-readable domain-specific language (DSL). It allows non-technical stakeholders, such as product owners and business analysts, to write executable specifications in a natural language format.
2. Step Definitions: Developers can write step definitions in Java to map Gherkin language statements to actual code implementations. This allows for the automation of acceptance criteria and facilitates collaboration between developers and non-technical team members.
3. Tagging: Cucumber allows you to tag scenarios and features, making it easy to organize and execute specific subsets of your test suite. This is particularly useful for running regression tests or testing specific features.
4. Data Tables: You can use data tables in scenarios to provide multiple input values and expected outcomes, enhancing test coverage without duplicating scenarios.
5. Hooks: Cucumber supports hooks, which are pre and post-execution actions that can be used for setup and teardown tasks, such as setting up test data or performing cleanup after a scenario.
6. Reports: Cucumber generates detailed test reports in various formats, including HTML, JSON, and XML, making it easier to analyze test results and track test coverage.
7. Integration: It seamlessly integrates with popular testing frameworks like JUnit and TestNG, making it easy to incorporate BDD into your existing testing ecosystem.