How to find the indexing value of a number in an integer array?

Java
1

I have a java related question - if we have an integer array of size 5. Then how can we find the indexing value of a number in this integer array?

PLEASE TAKE THE INTEGER ARRAY AS { 2,1,4,3,6 }

Earlier I tried doing this with the indexOf() method but there was an error when I ran the program.

2

Could you paste your code and clarify the intended behavior? A few inputs with expected output should suffice.