NettyUtil.java

/**
 * Helios, OpenSource Monitoring
 * Brought to you by the Helios Development Group
 *
 * Copyright 2007, Helios Development Group and individual contributors
 * as indicated by the @author tags. See the copyright.txt file in the
 * distribution for a full listing of individual contributors.
 *
 * This 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 software 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 software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org. 
 *
 */
package org.helios.apmrouter.util;

import org.jboss.netty.buffer.ChannelBuffer;

/**
 * <p>Title: NettyUtil</p>
 * <p>Description: Some static netty related helper routines </p> 
 * <p>Company: Helios Development Group LLC</p>
 * @author Whitehead (nwhitehead AT heliosdev DOT org)
 * <p><code>org.helios.apmrouter.util.NettyUtil</code></p>
 */

public class NettyUtil {
    public static final String NEWLINE = String.format("%n");
    private static final String[] BYTE2HEX = new String[256];
    private static final String[] HEXPADDING = new String[16];
    private static final String[] BYTEPADDING = new String[16];
    private static final char[] BYTE2CHAR = new char[256];

    static {
        int i;

        // Generate the lookup table for byte-to-hex-dump conversion
        for (i = 0; i < 10; i ++) {
            StringBuilder buf = new StringBuilder(3);
            buf.append(" 0");
            buf.append(i);
            BYTE2HEX[i] = buf.toString();
        }
        for (; i < 16; i ++) {
            StringBuilder buf = new StringBuilder(3);
            buf.append(" 0");
            buf.append((char) ('a' + i - 10));
            BYTE2HEX[i] = buf.toString();
        }
        for (; i < BYTE2HEX.length; i ++) {
            StringBuilder buf = new StringBuilder(3);
            buf.append(' ');
            buf.append(Integer.toHexString(i));
            BYTE2HEX[i] = buf.toString();
        }

        // Generate the lookup table for hex dump paddings
        for (i = 0; i < HEXPADDING.length; i ++) {
            int padding = HEXPADDING.length - i;
            StringBuilder buf = new StringBuilder(padding * 3);
            for (int j = 0; j < padding; j ++) {
                buf.append("   ");
            }
            HEXPADDING[i] = buf.toString();
        }

        // Generate the lookup table for byte dump paddings
        for (i = 0; i < BYTEPADDING.length; i ++) {
            int padding = BYTEPADDING.length - i;
            StringBuilder buf = new StringBuilder(padding);
            for (int j = 0; j < padding; j ++) {
                buf.append(' ');
            }
            BYTEPADDING[i] = buf.toString();
        }

        // Generate the lookup table for byte-to-char conversion
        for (i = 0; i < BYTE2CHAR.length; i ++) {
            if (i <= 0x1f || i >= 0x7f) {
                BYTE2CHAR[i] = '.';
            } else {
                BYTE2CHAR[i] = (char) i;
            }
        }
    }
    
    public static String formatBuffer(ChannelBuffer buffer, int index, int maxLength) {
		if(buffer==null || buffer.readableBytes()<1) return "";
		return "";
		//TBD !!!

    }
    

    public static String formatBuffer(ChannelBuffer buffer, int maxLength) {
		if(buffer==null || buffer.readableBytes()<1) return "";
		return formatBuffer(buffer.slice(0, buffer.readableBytes()>maxLength ? maxLength : buffer.readableBytes()));

    }
    
    public static String formatBuffer(ChannelBuffer buf) {
        int length = buf.readableBytes();
        int rows = length / 16 + (length % 15 == 0? 0 : 1) + 4;
        StringBuilder dump = new StringBuilder(rows * 80);

        dump.append(
                NEWLINE + "         +-------------------------------------------------+" +
                NEWLINE + "         |  0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f |" +
                NEWLINE + "+--------+-------------------------------------------------+----------------+");

        final int startIndex = buf.readerIndex();
        final int endIndex = buf.writerIndex();

        int i;
        for (i = startIndex; i < endIndex; i ++) {
            int relIdx = i - startIndex;
            int relIdxMod16 = relIdx & 15;
            if (relIdxMod16 == 0) {
                dump.append(NEWLINE);
                dump.append(Long.toHexString(relIdx & 0xFFFFFFFFL | 0x100000000L));
                dump.setCharAt(dump.length() - 9, '|');
                dump.append('|');
            }
            dump.append(BYTE2HEX[buf.getUnsignedByte(i)]);
            if (relIdxMod16 == 15) {
                dump.append(" |");
                for (int j = i - 15; j <= i; j ++) {
                    dump.append(BYTE2CHAR[buf.getUnsignedByte(j)]);
                }
                dump.append('|');
            }
        }

        if ((i - startIndex & 15) != 0) {
            int remainder = length & 15;
            dump.append(HEXPADDING[remainder]);
            dump.append(" |");
            for (int j = i - remainder; j < i; j ++) {
                dump.append(BYTE2CHAR[buf.getUnsignedByte(j)]);
            }
            dump.append(BYTEPADDING[remainder]);
            dump.append('|');
        }

        dump.append(
                NEWLINE + "+--------+-------------------------------------------------+----------------+");

        return dump.toString();
    }

}