Java ByteBuffer Dump hexDump(PrintStream ps, ByteBuffer bb)

Description

Prints a hex dump of the specified ByteBuffer to the specified PrintStream .

License

Open Source License

Parameter

Parameter	Description
ps	the print stream to write the hex dump to
bb	the byte buffer to be hex-dumped

Declaration

public static void hexDump(PrintStream ps, ByteBuffer bb) 

Method Source Code

//package com.java2s;
/*/* w w w  . j a  v  a  2 s.  com*/
 * Copyright (C) 2009-2013 Matthias Treydte <mt@waldheinz.de>
 *
 * This library is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as published
 * by the Free Software Foundation; either version 2.1 of the License, or
 * (at your option) any later version.
 *
 * This library 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 Lesser General Public
 * License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this library; If not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

import java.io.PrintStream;
import java.nio.ByteBuffer;

public class Main {
    /**
     * Prints a hex dump of the specified {@code ByteBuffer} to the specified
     * {@code PrintStream}. Only the "remaining" bytes in the buffer are
     * printed. The byte buffer is not modified by this method (i.e. no
     * bytes from the buffer are "consumed").
     *
     * @param ps the print stream to write the hex dump to
     * @param bb the byte buffer to be hex-dumped
     */
    public static void hexDump(PrintStream ps, ByteBuffer bb) {
        int inLine = 0;

        for (int pos = 0; pos < bb.remaining(); pos++) {
            final int b = bb.get(bb.position() + pos) & 0xff;

            if (inLine == 0)
                ps.print(hexOffset(pos, 6));

            ps.print(Character.forDigit(b / 16, 16));
            ps.print(Character.forDigit(b % 16, 16));
            ps.print(" ");

            inLine++;

            if (inLine == 8)
                ps.print("- ");

            if (inLine >= 16) {
                ps.print(": ");
                for (int i = 0; i < 16; i++) {
                    final byte get = bb.get(bb.position() + (pos - 15 + i));

                    ps.print(getChar(get));
                }

                ps.println();
                inLine = 0;
            }
        }

        if (inLine > 0) {

            for (int i = 0; i < (16 - inLine); i++)
                ps.print("   ");
            if (inLine < 8)
                ps.print("  ");
            ps.print(": ");

            for (int i = 0; i < inLine; i++) {
                final byte get = bb.get(bb.position() + bb.remaining() - inLine + i);

                ps.print(getChar(get));
            }

            ps.println();
        }
    }

    /**
     * Converts a integer value to an hex string which will have the specified
     * width.
     *
     * @param value the value to be converted to a hex string
     * @param width the desired width of the output string
     * @return the string representation of the value
     * @throws IllegalArgumentException if the {@code value} is too big for the
     *      specified {@code width}
     * @see Integer#toHexString(int)
     */
    public static String hexOffset(int value, int width) throws IllegalArgumentException {

        final String digits = Integer.toHexString(value);

        if (digits.length() > width)
            throw new IllegalArgumentException("value too big for width"); //NOI18N

        StringBuilder sb = new StringBuilder();
        for (int i = digits.length(); i < width; i++)
            sb.append("0");
        sb.append(digits);
        sb.append(" : ");

        return sb.toString();
    }

    /**
     * Returns the {@code char} corresponding to the specified {@code byte}.
     *
     * @param b the {@code byte} to convert to a {@code char}
     * @return the {@code char} for the specified {@code byte}, or '.' if
     *      the byte corresponds to no (printable) character
     */
    public static char getChar(byte b) {

        final char c = (char) b;
        final Character.UnicodeBlock bl = Character.UnicodeBlock.of(c);

        if (!Character.isISOControl(c) && bl != null && bl != Character.UnicodeBlock.SPECIALS) {

            return c;
        } else {
            return '.';
        }
    }
}

Related

1. dumpBytes(PrintStream ps, ByteBuffer buf)
2. dumpHexString(ByteBuffer bb)
3. dumpNextNBytes(ByteBuffer buffer, int n)
4. dumpToFile(ByteBuffer buf, String fileName)
5. hexDump(ByteBuffer buffer)
6. printByteDump(StringBuilder strBuilder, ByteBuffer data, int offset, int length, int columnNum)
7. setDecreasedBuffer(ByteBuffer memoryDumpReader, long baseAddressValue, int innerPointerOffset, long memoryDumpStartingOffset)
8. toHexDumpString(ByteBuffer data)