Java Hex Calculate toHex(StringBuffer buf, long value, int width)

Description

to Hex

License

Open Source License

Declaration

public static void toHex(StringBuffer buf, long value, int width) 

Method Source Code

//package com.java2s;

public class Main {
    public static final char[] HEX_CHARS = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D',
            'E', 'F' };

    /**//from   w ww . j a  va2  s  .com
     * The <code>toHex()</code> converts the specified long value into a hexadecimal string of the given with.
     * The value will be padded on the left with zero values to achieve the desired with.
     *
     * @param value the long value to convert to a string
     * @param width the desired length of the string
     * @return a hexadecimal string representation of the given value, padded on the left with zeroes to the
     *         length specified
     */
    public static String toHex(long value, int width) {
        char result[] = new char[width];
        return convertToHex(value, width, 0, result);
    }

    public static void toHex(StringBuffer buf, long value, int width) {
        if (value > (long) 1 << width * 4) {
            buf.append(Long.toHexString(value).toUpperCase());
            return;
        }

        for (int cntr = width - 1; cntr >= 0; cntr--)
            buf.append(HEX_CHARS[(int) (value >> (cntr * 4)) & 0xf]);
    }

    private static String convertToHex(long value, int width, int start, char[] result) {
        if (value > (long) 1 << width * 4)
            return Long.toHexString(value).toUpperCase();

        int i = start + width - 1;
        for (int cntr = 0; cntr < width; cntr++) {
            result[i - cntr] = HEX_CHARS[(int) (value >> (cntr * 4)) & 0xf];
        }

        return new String(result);
    }
}

Related

1. toHex(String source)
2. toHex(String str)
3. toHex(String string)
4. toHex(String txt)
5. toHex(String val)
6. toHex(StringBuilder s, byte b)
7. toHex00String(int c)
8. toHEX1(byte b)
9. toHex16(int w)