Java example source code file (Decode.java)

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Java - Java tags/keywords

byte, charset, decode, esc, exception, ss2, ss3, string, throwable, usage

The Decode.java Java example source code

/*
 * Copyright (c) 2008, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

/**/

public class Decode {
    private static boolean isAscii(char c) {
        return c < '\u0080';
    }

    private static boolean isPrintable(char c) {
        return ('\u0020' < c) && (c < '\u007f');
    }

    public static void main(String[] args) throws Throwable {
        if (args.length < 2)
            throw new Exception("Usage: java Decode CHARSET BYTE [BYTE ...]");
        String cs = args[0];
        byte[] bytes = new byte[args.length-1];
        for (int i = 1; i < args.length; i++) {
            String arg = args[i];
            bytes[i-1] =
                (arg.length() == 1 && isAscii(arg.charAt(0))) ?
                (byte) arg.charAt(0) :
                arg.equals("ESC") ? 0x1b :
                arg.equals("SO")  ? 0x0e :
                arg.equals("SI")  ? 0x0f :
                arg.equals("SS2") ? (byte) 0x8e :
                arg.equals("SS3") ? (byte) 0x8f :
                arg.matches("0x.*") ? Integer.decode(arg).byteValue() :
                Integer.decode("0x"+arg).byteValue();
        }
        String s = new String(bytes, cs);

        for (int j = 0; j < s.length(); j++) {
            if (j > 0)
                System.out.print(' ');
            char c = s.charAt(j);
            if (isPrintable(c))
                System.out.print(c);
            else if (c == '\u001b') System.out.print("ESC");
            else
                System.out.printf("\\u%04x", (int) c);
        }
        System.out.print("\n");
    }
}