Selenium is an open-source web-based automation tool. Java, on the other hand, is a high-level, class-based, object-oriented programming language. The unique thing about Selenium Java is the combination of these two elements: the robust automation capabilities of Selenium with the versatility and ubiquity of Java.

1. Compatibility: Selenium is compatible with multiple browsers, including Firefox, Chrome, Edge, Safari, and more. Therefore, tests written in Selenium can be run on virtually any web browser. Coupled with Java, which can run on any platform that supports the Java Virtual Machine (JVM), you have a highly versatile testing platform.

2. Community and Documentation: Java has one of the biggest programming communities, which means that support, in terms of troubleshooting and open-source libraries, is easily available. Selenium also has a very active community. This makes Selenium Java a reliable choice for web testing.

3. Advanced Interactions: Selenium provides the ability to simulate complex user interactions like clicking, double-clicking, drag-and-drop, and more. These can be written using Java, which provides robust exception handling and the ability to build complex logic into your tests.

4. Integration: Selenium Java integrates well with various tools. It’s compatible with testing frameworks like JUnit and TestNG. It also works with build tools like Maven and ANT, as well as continuous integration tools like Jenkins.

5. Scaling and Distributed Testing: With Selenium Grid and Java, you can perform distributed testing, i.e., executing tests on different machines with different browsers, simultaneously. This reduces the time taken for testing and accelerates the whole process.

6. Page Object Model: With Selenium Java, testers can use the Page Object Model (POM), which is an object-oriented class-based representation of a web page. This enhances the maintainability of the test code.

7. Test Driven Development (TDD) and Behavior Driven Development (BDD): Selenium Java supports both TDD and BDD approaches, making it a flexible choice for different teams and testing requirements. It can be integrated with BDD frameworks like Cucumber-JVM, JBehave, etc.

8. Robust Reporting: With Java’s powerful libraries and integration with frameworks like TestNG, Selenium Java provides robust reporting capabilities. Reports can include information about the number of test cases passed, failed, and their detailed breakdown.

In conclusion, Selenium Java is a powerful combination that provides extensive capabilities for web automation testing. It harnesses the robustness of Java and the versatility of Selenium, making it a popular choice for testers around the globe.