Convert Encoding : Encoding « I18N « Java

Convert Encoding

 * Copyright (c) 2000 David Flanagan.  All rights reserved.
 * This code is from the book Java Examples in a Nutshell, 2nd Edition.
 * It is provided AS-IS, WITHOUT ANY WARRANTY either expressed or implied.
 * You may study, use, and modify it for any non-commercial purpose.
 * You may distribute it non-commercially as long as you retain this notice.
 * For a commercial use license, or to purchase the book (recommended),
 * visit


/** A program to convert from one character encoding to another */
public class ConvertEncoding {
  public static void main(String[] args) {
    String from = null, to = null;
    String infile = null, outfile = null;
    for (int i = 0; i < args.length; i++) { // Parse command-line arguments.
      if (i == args.length - 1)
        usage(); // All args require another.
      if (args[i].equals("-from"))
        from = args[++i];
      else if (args[i].equals("-to"))
        to = args[++i];
      else if (args[i].equals("-in"))
        infile = args[++i];
      else if (args[i].equals("-out"))
        outfile = args[++i];

    try {
      convert(infile, outfile, from, to);
    } // Attempt conversion.
    catch (Exception e) { // Handle exceptions.

  public static void usage() {
    System.err.println("Usage: java ConvertEncoding <options>\n"
        + "Options:\n\t-from <encoding>\n\t" + "-to <encoding>\n\t"
        + "-in <file>\n\t-out <file>");

  public static void convert(String infile, String outfile, String from,
      String to) throws IOException, UnsupportedEncodingException {
    // Set up byte streams.
    InputStream in;
    if (infile != null)
      in = new FileInputStream(infile);
      in =;
    OutputStream out;
    if (outfile != null)
      out = new FileOutputStream(outfile);
      out = System.out;

    // Use default encoding if no encoding is specified.
    if (from == null)
      from = System.getProperty("file.encoding");
    if (to == null)
      to = System.getProperty("file.encoding");

    // Set up character streams.
    Reader r = new BufferedReader(new InputStreamReader(in, from));
    Writer w = new BufferedWriter(new OutputStreamWriter(out, to));

    // Copy characters from input to output. The InputStreamReader
    // converts from the input encoding to Unicode, and the
    // OutputStreamWriter converts from Unicode to the output encoding.
    // Characters that cannot be represented in the output encoding are
    // output as '?'
    char[] buffer = new char[4096];
    int len;
    while ((len = != -1)
      // Read a block of input.
      w.write(buffer, 0, len); // And write it out.
    r.close(); // Close the input.
    w.close(); // Flush and close output.


Related examples in the same category

1.Utility class for working with character sets
2.Utility methods for ASCII character checking.
3.Reader for UCS-2 and UCS-4 encodings. (i.e., encodings from ISO-10646-UCS-(2|4)).
4.Conversions between IANA encoding names and Java encoding names, and vice versa.
5.ASCII character handling functions
6.This class represents an encoding.
7.Provides information about encodings.
8.Codec for the Quoted-Printable section of (RFC 1521)
9.ISO 8859-8, ASCII plus Hebrew
10.TIS-620 does not have the non-breaking space or the C1 controls.
11.ISO-8859-1; a.k.a. Latin-1
12.ISO 8859-2, a.k.a. Latin-2
13.ISO 8859-3
14.ISO 8859-4, Latin plus the characters needed for Greenlandic, Icelandic, and Lappish.
15.ISO 8859-9 for Turkish.
16.ISO-8859-10, for Lithuanian, Estonian, Greenlandic, Icelandic, Inuit, Lappish, and other Northern European languages.
17.ISO-8859-13, for Latvian and other Baltic languages.
18.ISO-8859-14, for Gaelic, Welsh, and other Celtic languages.
19.ISO 8859-9 for Western Europe. Includes the Euro sign and several uncommon French letters
20.ISO 8859-16, Romanian
21.ASCII Writer
22.UCS Writer
23.Unicode Writer
24.Whether a character is or is not available in a particular encoding
25.ISO 8859-6, ASCII plus Arabic
26.ISO 8859-5, ASCII plus Cyrillic (Russian, Byelorussian, etc.)
27.ISO 8859-7, ASCII plus Greek
28.IANA to Java Mapping
29.Java to IANA Mapping
30.EncodingMap is a convenience class which handles conversions between IANA encoding names and Java encoding names, and vice versa.
31.Get file encoding