How to find the index of an element in an int array?

Question

How can I find an index of a certain value in a Java array of type int?

I tried using Arrays.binarySearch on my unsorted array, it only som

Answer 1

You need to sort values before using binary search. Otherwise, the manual way is to try all ints in your tab.

public int getIndexOf( int toSearch, int[] tab )
{
  for( int i=0; i< tab.length ; i ++ )
    if( tab[ i ] == toSearch)
     return i;

  return -1;
}//met

An alternative method could be to map all index for each value in a map.

tab[ index ] = value;
if( map.get( value) == null || map.get( value) > index )
    map.put( value, index );

and then map.get(value) to get the index.

Regards, Stéphane

@pst, thanks for your comments. Can you post an other alternative method ?