冒泡排序算法

                int[] array = new int[10];
		//将10个随机整数放入数组
		for(int i = 0;i< array.length;i++){
			array[i] = (int) (Math.random()*100);
			System.out.print(array[i]+" ");
		}
		for (int i = 0;i < array.length;i++){
			for(int j = 0;j<array.length-1-i;j++){
				if(array[j] > array[j+1]){
					int temp = array[j];
					array[j] = array[j+1];
					array[j+1] = temp;
				}
			}
		}
		System.out.println("冒泡排序后");
		for (int i = 0;i<array.length;i++){
			System.out.print(array[i]+" ");
		}

特别注意内层array.length-1后还要再减去i。(好处是让上一层已经排好序的数不再参与排序)

方式二： 

 public static void bubbleSort(int[] arr) {
        if (arr == null || arr.length < 2) {
            return;
        }
        int size = arr.length;
        // 0~end  之间每两个比较  前面比后面大的话  交换
        // 0 1   1 2   2 3  ...  end-1 end
        for (int end = size -1; end >= 0; end--) {
            for (int second = 1; second <= end; second++) {
                if (arr[second -1] > arr[second]) {
                    swap(arr, second -1, second);
                }
            }
        }
        System.out.println(Arrays.toString(arr));
    }

    public static void bubbleSort(int[] arr) {
        if (arr == null || arr.length < 2) {
            return;
        }

        int N = arr.length;
        for (int end = N - 1;end >= 0;end--) {
            for (int second = 1;second<=end;second++) {
                if (arr[second -1] > arr[second]) {
                    int temp = arr[second];
                    arr[second] = arr[second -1];
                    arr[second -1] = temp;
                }
            }
        }
    }