How to random a numbers ....

For Example this are my inputs ..

arr1[0] : 5
arr1[1] : 1
arr1[2] : 2
arr1[3] : 3
arr1[4] : 6
arr1[5] : 4

how to random this numbers .... using java ....

when i want to random those numbers it should be random .... for example i want to randomize those numbers 3 times ... how can do it /