I don't understand what you're trying to do, but I can comment on your code:
letters[ctr_x] = letters[ctr_x];
This is a noop: it sets an array element value to the value it already has.
char[] lettersr1 = null;
for(int ctr_x = (ctr_r1 + 2) ; ctr_x < letters.length - 2 ; ctr_x++) {
lettersr1[ctr_x] = letters[ctr_x];
This obviously causes a NullPointerException, since you're trying to access an array which is null. You must initialize the array before being able to modify it:
char[] lettersr1 = new char[someLength];
Additional note: you should choose better names for your variables. The names should tell what the variable represents, and they should respect the Java naming conventions (no underscores in variable names, camelCase). ctr_x
, ctr_r1
and lettersr1
don't mean anything.
EDIT:
I'm still not sure what you want to do, and why you don't simply use substring()
, but here's how to transform EUCHARIST to HARIST:
char[] eucharist = "EUCHARIST".toCharArray();
char[] harist = new char[6];
System.arraycopy(eucharist, 3, harist, 0, 6);
String haristAsString = new String(harist);
System.out.println(haristAsString);
// or
char[] harist2 = new char[6];
for (int i = 0; i < 6; i++) {
harist2[i] = eucharist[i + 3];
}
String harist2AsString = new String(harist2);
System.out.println(harist2AsString);
// or
String harist3AsString = "EUCHARIST".substring(3);
char[] harist3 = harist3AsString.toCharArray();
System.out.println(harist3AsString);