ascii.java

一个简单的visio程序。

package servlet.util;


public class Ascii
{

    public static int toUpper(int i)
    {
        return toUpper[i & 0xff] & 0xff;
    }

    public static int toLower(int i)
    {
        return toLower[i & 0xff] & 0xff;
    }

    public static boolean isAlpha(int i)
    {
        return isAlpha[i & 0xff];
    }

    public static boolean isUpper(int i)
    {
        return isUpper[i & 0xff];
    }

    public static boolean isLower(int i)
    {
        return isLower[i & 0xff];
    }

    public static boolean isWhite(int i)
    {
        return isWhite[i & 0xff];
    }

    public static boolean isDigit(int i)
    {
        return isDigit[i & 0xff];
    }

    public static int parseInt(byte abyte0[], int i, int j)
        throws NumberFormatException
    {
        byte byte0;
        if(abyte0 == null || j <= 0 || !isDigit(byte0 = abyte0[i++]))
            throw new NumberFormatException();
        int k;
        for(k = byte0 - 48; --j > 0; k = (k * 10 + byte0) - 48)
            if(!isDigit(byte0 = abyte0[i++]))
                throw new NumberFormatException();

        return k;
    }

    public Ascii()
    {
    }

    private static final byte toUpper[];
    private static final byte toLower[];
    private static final boolean isAlpha[];
    private static final boolean isUpper[];
    private static final boolean isLower[];
    private static final boolean isWhite[];
    private static final boolean isDigit[];

    static 
    {
        toUpper = new byte[256];
        toLower = new byte[256];
        isAlpha = new boolean[256];
        isUpper = new boolean[256];
        isLower = new boolean[256];
        isWhite = new boolean[256];
        isDigit = new boolean[256];
        for(int i = 0; i < 256; i++)
        {
            toUpper[i] = (byte)i;
            toLower[i] = (byte)i;
        }

        for(int j = 97; j <= 122; j++)
        {
            int k = (j + 65) - 97;
            toUpper[j] = (byte)k;
            toLower[k] = (byte)j;
            isAlpha[j] = true;
            isAlpha[k] = true;
            isLower[j] = true;
            isUpper[k] = true;
        }

        isWhite[32] = true;
        isWhite[9] = true;
        isWhite[13] = true;
        isWhite[10] = true;
        isWhite[12] = true;
        isWhite[8] = true;
        for(int l = 48; l <= 57; l++)
            isDigit[l] = true;

    }
}