JAVA Syntax Meaning Inquiry

public static void bubbleSort(int[] arr) {
    for(int i = 0; i < arr.length; i++) {
        for(int j = 0; j < arr.length - i -1 ; j++) {
            if(arr[j] > arr[j+1]) {
                int temp = arr[j+1];
                arr[j+1] = arr[j];
                arr[j] = temp;
            }
        }
    }
}
public static void main(String[] args) {
    int[] arr = new int[]{3,6,41,2,4,1,5,743};
    BubbleSort Sort = new BubbleSort();
    Sort.bubbleSort(arr);
    for(int i : arr) { 
        System.out.print(i+" ");
    }
}