The following could work for you, see the method search(byte[] input, byte[] searchedFor)
which returns the index where the first match matches, or -1.
public class SearchBuffer {
public static void main(String[] args) throws UnsupportedEncodingException {
String charset= "US-ASCII";
byte[] searchedFor = "ciao".getBytes(charset);
byte[] input = "aaaciaaaciaojjcia".getBytes(charset);
int idx = search(input, searchedFor);
System.out.println("index: "+idx); //should be 8
}
public static int search(byte[] input, byte[] searchedFor) {
//convert byte[] to Byte[]
Byte[] searchedForB = new Byte[searchedFor.length];
for(int x = 0; x<searchedFor.length; x++){
searchedForB[x] = searchedFor[x];
}
int idx = -1;
//search:
Deque<Byte> q = new ArrayDeque<Byte>(input.length);
for(int i=0; i<input.length; i++){
if(q.size() == searchedForB.length){
//here I can check
Byte[] cur = q.toArray(new Byte[]{});
if(Arrays.equals(cur, searchedForB)){
//found!
idx = i - searchedForB.length;
break;
} else {
//not found
q.pop();
q.addLast(input[i]);
}
} else {
q.addLast(input[i]);
}
}
return idx;
}
}