Implementing a recursive function in Java involves writing a function that calls itself to solve a problem by breaking it down into smaller, more manageable subproblems. Recursive functions consist of two main parts: the base case(s) and the recursive case(s). The base case defines when the recursion should stop, and the recursive case defines how the function calls itself. Here's a general outline of how to implement a recursive function in Java:

```java
public class RecursiveExample {
    public static void main(String[] args) {
        // Call the recursive function
        int result = recursiveFunction(5);
        System.out.println("Result: " + result);
    }

    // Recursive function
    static int recursiveFunction(int n) {
        // Base case(s)
        if (n <= 0) {
            // Return a value or perform an action when the base case is reached
            return 0;
        }

        // Recursive case(s)
        int subproblemResult = recursiveFunction(n - 1); // Recursive call
        // Perform operations on the subproblem result and return the final result
        int result = n + subproblemResult;

        return result;
    }
}
```

In this example, we implement a simple recursive function called `recursiveFunction` that calculates the sum of integers from 1 to `n`. Here's how it works:

1. The base case is defined as `if (n <= 0)`. When `n` becomes less than or equal to 0, we return a value (in this case, 0) or perform an action to stop the recursion. This is essential to prevent infinite recursion.

2. In the recursive case, we make a recursive call to `recursiveFunction(n - 1)`, which solves a smaller subproblem (summing integers from 1 to `n - 1`).

3. After obtaining the result of the subproblem (`subproblemResult`), we perform additional operations (in this case, adding `n` to the subproblem result) to calculate the final result.

4. The final result is returned to the caller.

5. In the `main` method, we call `recursiveFunction(5)` to find the sum of integers from 1 to 5 and then print the result.

Remember that it's crucial to define base cases correctly to ensure that the recursion terminates. Recursive functions are a powerful tool, but they can lead to stack overflow errors if not used carefully. Also, excessive recursion may result in performance issues, so consider alternative approaches for solving complex problems when necessary.