org.apache.catalina.util.Base64 Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.catalina.util;
import java.io.UnsupportedEncodingException;
import org.apache.tomcat.util.buf.ByteChunk;
import org.apache.tomcat.util.buf.CharChunk;
/**
* This class provides encode/decode for RFC 2045 Base64 as defined by
* RFC 2045, N. Freed and N. Borenstein. RFC 2045:
* Multipurpose Internet Mail Extensions (MIME) Part One: Format of
* Internet Message Bodies. Reference 1996
*
* @author Jeffrey Rodriguez
* @version $Id: Base64.java 1043105 2010-12-07 15:42:32Z markt $
*/
public final class Base64
{
private static final int BASELENGTH = 255;
private static final int LOOKUPLENGTH = 64;
private static final int TWENTYFOURBITGROUP = 24;
private static final int EIGHTBIT = 8;
private static final int SIXTEENBIT = 16;
private static final int FOURBYTE = 4;
private static final int SIGN = -128;
private static final byte PAD = (byte) '=';
private static byte [] base64Alphabet = new byte[BASELENGTH];
private static byte [] lookUpBase64Alphabet = new byte[LOOKUPLENGTH];
static
{
for (int i = 0; i < BASELENGTH; i++ )
{
base64Alphabet[i] = -1;
}
for (int i = 'Z'; i >= 'A'; i--)
{
base64Alphabet[i] = (byte) (i - 'A');
}
for (int i = 'z'; i>= 'a'; i--)
{
base64Alphabet[i] = (byte) (i - 'a' + 26);
}
for (int i = '9'; i >= '0'; i--)
{
base64Alphabet[i] = (byte) (i - '0' + 52);
}
base64Alphabet['+'] = 62;
base64Alphabet['/'] = 63;
for (int i = 0; i <= 25; i++ )
lookUpBase64Alphabet[i] = (byte) ('A' + i);
for (int i = 26, j = 0; i <= 51; i++, j++ )
lookUpBase64Alphabet[i] = (byte) ('a'+ j);
for (int i = 52, j = 0; i <= 61; i++, j++ )
lookUpBase64Alphabet[i] = (byte) ('0' + j);
lookUpBase64Alphabet[62] = (byte) '+';
lookUpBase64Alphabet[63] = (byte) '/';
}
public static boolean isBase64( String isValidString )
{
return isArrayByteBase64(isValidString.getBytes());
}
public static boolean isBase64( byte octect )
{
//shall we ignore white space? JEFF??
return (octect == PAD || base64Alphabet[octect] != -1);
}
public static boolean isArrayByteBase64( byte[] arrayOctect )
{
int length = arrayOctect.length;
if (length == 0)
{
// shouldn't a 0 length array be valid base64 data?
// return false;
return true;
}
for (int i=0; i < length; i++)
{
if ( !Base64.isBase64(arrayOctect[i]) )
return false;
}
return true;
}
/**
* Encodes hex octets into Base64.
*
* @param binaryData Array containing binary data to encode.
* @return Base64-encoded data.
*/
public static String encode(byte[] binaryData) {
int lengthDataBits = binaryData.length*EIGHTBIT;
int fewerThan24bits = lengthDataBits%TWENTYFOURBITGROUP;
int numberTriplets = lengthDataBits/TWENTYFOURBITGROUP;
byte encodedData[] = null;
if (fewerThan24bits != 0)
{
//data not divisible by 24 bit
encodedData = new byte[ (numberTriplets + 1 ) * 4 ];
}
else
{
// 16 or 8 bit
encodedData = new byte[ numberTriplets * 4 ];
}
byte k = 0, l = 0, b1 = 0, b2 = 0, b3 = 0;
int encodedIndex = 0;
int dataIndex = 0;
int i = 0;
//log.debug("number of triplets = " + numberTriplets);
for ( i = 0; i