with java program

keep it simple please

Question 2.3: (Perfect number) A positive integer is called a perfect number if it is equal to the sum of all of its positive divisors, excluding itself. For example, 6 is the first perfect number because 6=3+2+1. The next is 28=14+7+4+2+1. There are four perfect number less than 10000 . Write a program Perfect.java to find all these four numbers