Java: I am comparing two strings but did not recognize it

I have this problem:

I wrote this function because I need to get the index of the occurrence of a particular string st

in a String array

static public int indicestring(String[] array, String st) {
    int ret = -1;

    for (int i = 0; i < array.length; i++){
        if (st.equals(array[i])) {
            ret=i;
            break;
        }
    }

    return ret;
}

      

        
        
        
      

    

Then I called:

System.out.println("indicestring(NODO,"ET2"));

      

        
        
        
      

    

and I got the correct number.

But when I do this:

String[] arcos2 = linea.split("-");//reading from a file and separating by "-"
String aux = arcos2[1];

System.out.println(arcos2[1]);
System.out.println(aux);

if (aux.equals(arcos2[1])) {
    System.out.println("Is equal 1");
}

if (aux.equals("ET2")) {
    System.out.println("Is equal 2");
}

if ("ET2".equals(aux)) {
    System.out.println("is equal 3");
}

      

        
        
        
      

    

The first two prints were ET2

, but then it only printed from 3 ifs: "Is is equal to 1" .... The thing is, I have almost 200 nodes like "ET2" and only 3 don't work and give me - 1 in the first function ...

My question is: I am using the wrong arrays to store and compare data, because if aux = arcos2 [1] = "ET2" then why is' aux.equals ("ET2") 'or' arcos2 [1] .equals ("ET2 " ) does not work ? Is there another feature you can recommend to try? (I tried changing the equals with compareTo() == 0

and that didn't work either, and the fix was recommended.)

Earlier I had a similar error when I was comparing two arrays like this:

if(a[0] == b[0] && a[1] == b[1])

      

        
        
        
      

    

There was a case that was clearly right, but it was ignored ... But it got fixed when I changed it to:

if (Arrays.equals(a, b))

      

        
        
        
      

    

Maybe some changes like this