You just need nested loop, that will surve the purpose,
public class HelloWorld {
   public static void main(String a[]) {
      int[] arr1 = {4,7,3,9,2};
      int[] arr2 = {3,2,12,9,40,32,4};      
      for(int i = 0;i < arr1.length; i++) {
         for(int j = 0; j < arr2.length; j++) {
            if(arr1[i] == arr2[j]) { 
               System.out.println(arr1[i]);
            } 
         } 
      }
   }
}