// copyright (c) Hiroyuki Murata 1997.
// free to use, distribute or modify.
import java.io.*;

public class Ue2Utf {

    static String usage =
        " Unicode-escape to UTF-8 Converter for JDK 1.0.2.\n" +
        "  Usage:\n" +
        "   1) Replace all \'\\\'s in Japanese native file with \'\\\\\'s.\n" +
        "   2) Use J2Uc (or native2ascii) to generate \"inputfile\".\n" +
        "   3) java Ue2Utf inputfile outputfile\n"
    ;

    static final int MAXLEN = 1024;
    static char[] buf = new char[MAXLEN];

    static public void main(String[] args) {
        if (args.length < 2) {
            System.out.print(usage);
            System.exit(0);
        }

        try {
            DataInputStream dis = new DataInputStream (
                new BufferedInputStream(
                    new FileInputStream(args[0])
                )
            );
            DataOutputStream dos = new DataOutputStream (
                new BufferedOutputStream(
                    new FileOutputStream(args[1])
                )
            );

            char[] unibuf = new char[4];
            char c1, c2=0;
            int column = 0;

            try {
                for (;;) {
                    c1 = c2;
                    c2 = (char)dis.readUnsignedByte();
                    if (column >= MAXLEN) {
                        System.err.println("too long line!");
                        System.exit(1);
                    }

                    if (c1=='\\' && c2=='u') {
                        for (int i=0; i<4; i++)
                            unibuf[i] = (char)dis.readUnsignedByte();
                        buf[column-1] = (char)Integer.parseInt(
                            new String(unibuf), 16
                        );
                    } else if (c1=='\\' && c2=='\\') {
                        c2 = 0;
                    } else {
                        buf[column++] = c2;
                    }


                    if (c2=='\n') {
                        String line = new String(buf, 0, column);
                        dos.writeUTF(line);
                        //System.out.print(line);
                        column = 0;
                    }
                }
            } catch (EOFException e) {
                dos.close();
                dis.close();
            }

        } catch (FileNotFoundException e) {
            System.err.println("file " + args[0] + " not found.");
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}