Bubble sort in java | sorting algorithms

class bubble{
   public static void main(String args[]){
      int a[] = {4, 3, 2, 1};
      int n = a.length;
      for (int i = 0; i <= n-1; i++){
         for (int j = 0; j < n-1; j++){    
            if (a[j+1] < a[j]){
            int temp = a[j+1];
            a[j+1] = a[j];
            a[j] = temp;
            }
         }
      }
      for (int item: a ){ 
         System.out.print(item+" ");
      }
   }
}

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