/*
 * Copyright (c) 2005, 2006, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code 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 General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */
/*
 * @(#)ASCIIUtility.java      1.9 02/03/27
 */


package com.sun.xml.internal.messaging.saaj.packaging.mime.util;

import com.sun.xml.internal.messaging.saaj.util.ByteOutputStream;

import java.io.*;

public class ASCIIUtility {

    // Private constructor so that this class is not instantiated
    private ASCIIUtility() { }
	
    	
    /**
     * Convert the bytes within the specified range of the given byte 
     * array into a signed integer in the given radix . The range extends 
     * from <code>start</code> till, but not including <code>end</code>. <p>
     *
     * Based on java.lang.Integer.parseInt()
     */
    public static int parseInt(byte[] b, int start, int end, int radix)
		throws NumberFormatException {
	if (b == null)
	    throw new NumberFormatException("null");
	
	int result = 0;
	boolean negative = false;
	int i = start;
	int limit;
	int multmin;
	int digit;

	if (end > start) {
	    if (b[i] == '-') {
		negative = true;
		limit = Integer.MIN_VALUE;
		i++;
	    } else {
		limit = -Integer.MAX_VALUE;
	    }
	    multmin = limit / radix;
	    if (i < end) {
		digit = Character.digit((char)b[i++], radix);
		if (digit < 0) {
		    throw new NumberFormatException(
			"illegal number: " + toString(b, start, end)
			);
		} else {
		    result = -digit;
		}
	    }
	    while (i < end) {
		// Accumulating negatively avoids surprises near MAX_VALUE
		digit = Character.digit((char)b[i++], radix);
		if (digit < 0) {
		    throw new NumberFormatException("illegal number");
		}
		if (result < multmin) {
		    throw new NumberFormatException("illegal number");
		}
		result *= radix;
		if (result < limit + digit) {
		    throw new NumberFormatException("illegal number");
		}
		result -= digit;
	    }
	} else {
	    throw new NumberFormatException("illegal number");
	}
	if (negative) {
	    if (i > start + 1) {
		return result;
	    } else {	/* Only got "-" */
		throw new NumberFormatException("illegal number");
	    }
	} else {
	    return -result;
	}
    }

    /**
     * Convert the bytes within the specified range of the given byte 
     * array into a String. The range extends from <code>start</code>
     * till, but not including <code>end</code>. <p>
     */
    public static String toString(byte[] b, int start, int end) {
	int size = end - start;
	char[] theChars = new char[size];

	for (int i = 0, j = start; i < size; )
	    theChars[i++] = (char)(b[j++]&0xff);
	
	return new String(theChars);
    }

    public static byte[] getBytes(String s) {
	char [] chars= s.toCharArray();
	int size = chars.length;
	byte[] bytes = new byte[size];
    	
	for (int i = 0; i < size;)
	    bytes[i] = (byte) chars[i++];
	return bytes;
    }

    /**
     *
     * @deprecated
     *      this is an expensive operation that require an additional
     *      buffer reallocation just to get the array of an exact size.
     *      Unless you absolutely need the exact size array, don't use this.
     *      Use {@link ByteOutputStream} and {@link ByteOutputStream#write(InputStream)}.
     */
    public static byte[] getBytes(InputStream is) throws IOException {
        ByteOutputStream bos = new ByteOutputStream();
        try {
            bos.write(is);
        } finally {
            is.close();
        }
        return bos.toByteArray();
    }
}