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/*******************************************************************************
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 * File: P2_EncDec.java
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 * Author: Ira W. Snyder (devel@irasnyder.com)
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 * Class: CS380 - Computer Networking
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 *
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 * Assignment: Project #2
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 * Date Last Modified: 2006-02-04
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 *
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 * Purpose: Encode / Decode a number to / from 4B5B Encoding.
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 *
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 ******************************************************************************/
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import java.io.*;
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import java.io.*;
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import java.util.*;
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import java.util.*;
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public class P2_EncDec
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public class P2_EncDec
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{
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{
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    /*
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    /*
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    private final byte[][] encodingTable = {
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    private static final byte[][] encodingTable = {
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        { 0x0, 0x1E },
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        { 0x0, 0x1E },
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        { 0x1, 0x09 },
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        { 0x1, 0x09 },
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        { 0x2, 0x14 },
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        { 0x2, 0x14 },
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        { 0x3, 0x15 },
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        { 0x3, 0x15 },
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        { 0x4, 0x0A },
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        { 0x4, 0x0A },
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        { "1101", "11011" },
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        { "1101", "11011" },
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        { "1110", "11100" },
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        { "1110", "11100" },
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        { "1111", "11101" }};
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        { "1111", "11101" }};
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    /**
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     * Method: convert4B()
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     * Purpose: Convert a number from it's 4B representation to the
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     * corresponding 5B representation.
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     */
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    public static String convert4B (String _4BNum)
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    public static String convert4B (String _4BNum)
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    {
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    {
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        int i = encodingTable.length - 1;
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        int i = encodingTable.length - 1;
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        for (; i >= 0; i--)
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        for (; i >= 0; i--)
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                return encodingTable[i][1];
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                return encodingTable[i][1];
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        throw new IllegalArgumentException();
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        throw new IllegalArgumentException();
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    }
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    }
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    /**
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     * Method: convert5B()
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     * Purpose: Convert a number from it's 5B representation to the
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     * corresponding 4B representation.
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     */
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    public static String convert5B (String _5BNum)
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    public static String convert5B (String _5BNum)
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    {
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    {
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        int i = encodingTable.length - 1;
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        int i = encodingTable.length - 1;
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        for (; i>=0; i--)
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        for (; i>=0; i--)
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            if (encodingTable[i][1].equals(_5BNum))
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            if (encodingTable[i][1].equals(_5BNum))
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                return encodingTable[i][0];
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                return encodingTable[i][0];
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        throw new IllegalArgumentException();
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        throw new IllegalArgumentException();
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    }
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    }
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    public static void main (String[] args) throws Exception
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    {
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        String conv4 = "1000";
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        String conv5 = "11100";
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        System.out.printf ("Converting %s -> %s\n", conv4, convert4B (conv4));
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        System.out.printf ("Converting %s -> %s\n", conv5, convert5B (conv5));
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    }
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}
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}
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