Here is a basic Java function that takes an array of 10 items and segments it into arrays of 3:

```
public static int[][] segmentArray(int[] arr) {
    int[][] result = new int[4][3];
    int index = 0;
    for(int i = 0; i < result.length; i++) {
        for(int j = 0; j < result[i].length; j++) {
            if(index < arr.length) {
                result[i][j] = arr[index];
                index++;
            }
        }
    }
    return result;
}
```

This function creates a 2D array with 4 rows and 3 columns, which can hold the segmented arrays. It then uses a nested loop to iterate through the rows and columns of the 2D array and assigns values from the original array to each cell.

The function returns the segmented 2D array. Note that if the original array does not have a length that is a multiple of 3, some rows in the 2D array will contain 0s.
Scrivi una funzione Java che segmenta un array di 10 elementi in array di 3.