 # Java Program to Implement Bubble Sort algorithm

To understand this example, you should have the knowledge of the following Java programming topics:

## Example: Java Program to Implement Bubble Sort Algorithm

``````// import the Class
import java.util.Arrays;
import java.util.Scanner;

class Main {

// create an object of scanner
// to take input from the user
Scanner input = new Scanner(System.in);

// method to perform bubble sort
void bubbleSort(int array[]) {
int size = array.length;

// for ascending or descending sort
System.out.println("Choose Sorting Order:");
System.out.println("1 for Ascending \n2 for Descending");
int sortOrder = input.nextInt();

// run loops two times
// first loop access each element of the array
for (int i = 0; i < size - 1; i++)

// second loop performs the comparison in each iteration
for (int j = 0; j < size - i - 1; j++)

// sort the array in ascending order
if (sortOrder == 1) {
if (array[j] > array[j + 1]) {

// swap if left element is greater than right
int temp = array[j];
array[j] = array[j + 1];
array[j + 1] = temp;
}
}

// sort the array in descending order
else {
if (array[j] < array[j + 1]) {

// swap if left element is smaller than right
int temp = array[j];
array[j] = array[j + 1];
array[j + 1] = temp;
}
}

}

// driver code
public static void main(String args[]) {

// create an array
int[] data = { -2, 45, 0, 11, -9 };

// create an object of Main class
Main bs = new Main();

// call the method bubbleSort using object bs
// pass the array as the method argument
bs.bubbleSort(data);
System.out.println("Sorted Array in Ascending Order:");

// call toString() of Arrays class
// to convert data into the string
System.out.println(Arrays.toString(data));
}
}``````

Output 1

```Choose Sorting Order:
1 for Ascending
2 for Descending
1
Sorted Array:
[-9, -2, 0, 11, 45]```

In this case, we have entered 1 as input. Hence, the program sort the array in ascending order.

Output 2

```Choose Sorting Order:
1 for Ascending
2 for Descending
2
Sorted Array:
[45, 11, 0, -2, -9]```

In this case, we have entered 2 as input. Hence, the program sort the array in descending order.