Seek for an array of bytes[]/chars[] in an OutputStream/Reader in java

StreamSeeker.java

import java.io.IOException;
import java.io.InputStream;
import java.io.Reader;
import java.io.StringReader;

public class StreamSeeker {

    public static int seek(InputStream stream, byte[] bytes) throws IOException {
        boolean[] checks = new boolean[bytes.length];
        for (int s = bytes.length, z = 0, i = 0, x; (x = stream.read()) != -1; z++, i = i ==  s - 1 ? 0 : i + 1) {
            for (int j = 0; j < s; j++, i = i == 0 ? s - 1 : i - 1) {
                if ((checks[i] = x == bytes[j] && (checks[i] || j == 0)) && j == s - 1) {
                    return z - s + 1;
                }
            }
        }
        return -1;
    }

    public static int seek(Reader reader, char[] chars) throws IOException {
        boolean[] checks = new boolean[chars.length];
        for (int s = chars.length, z = 0, i = 0, x; (x = reader.read()) != -1; z++, i = i ==  s - 1 ? 0 : i + 1) {
            for (int j = 0; j < s; j++, i = i == 0 ? s - 1 : i - 1) {
                if ((checks[i] = x == chars[j] && (checks[i] || j == 0)) && j == s - 1) {
                    return z - s + 1;
                }
            }
        }
        return -1;
    }

    public static int seek(Reader reader, String string) throws IOException {
        return seek(reader, string.toCharArray());
    }
}