Encode.java

import java.io.*;
import java.nio.*;
import java.nio.file.*;
public class Encode {
    private static final byte INIT_BYTE = (byte) 0x17;
    private static final byte ESCAPE_BYTE = (byte) 0x18;
    private static final byte EXIT_BYTE = (byte) 0x19;
    public static void main(String[] args) throws Exception {
        try (InputStream in = System.in; OutputStream out = Files.newOutputStream(Paths.get("./encoded.jar"))) {
            int read = -1;
            out.write(INIT_BYTE);
            while ((read = in.read()) != -1) {
                if (read == INIT_BYTE || read == ESCAPE_BYTE || read == EXIT_BYTE) {
                    out.write(ESCAPE_BYTE);
                }
                out.write(read);
            }
            out.write(EXIT_BYTE);
        }
    }
}