package net.me2day.java.util;
| /*
| * @(#)BASE64.java
| *
| * Copyright (c) 2001-2002, JangHo Hwang
| * All rights reserved.
| *
| * Redistribution and use in source and binary forms, with or without
| * modification, are permitted provided that the following conditions
| * are met:
| *
| * 1. Redistributions of source code must retain the above copyright
| * notice, this list of conditions and the following disclaimer.
| *
| * 2. Redistributions in binary form must reproduce the above copyright
| * notice, this list of conditions and the following disclaimer in the
| * documentation and/or other materials provided with the distribution.
| *
| * 3. Neither the name of the JangHo Hwang nor the names of its contributors
| * may be used to endorse or promote products derived from this software
| * without specific prior written permission.
| *
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
| * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
| * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
| * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR
| * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
| * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
| * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
| * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
| * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
| * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
| * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
| *
| * $Id: BASE64.java,v 1.1 2007/02/28 08:43:11 xrath Exp $
| */
|
| import java.io.ByteArrayInputStream;
| import java.io.ByteArrayOutputStream;
| /**
| * BASE64 (RFC 1521)를 직접 구현한 클래스이다.
| * <p>
| * 사용법은 간단하며 다음과 같다.
| * <p>
| * <pre><code>
| * String str = "안녕하세요 오랜만입니다." );
| *
| * BASE64 b = new BASE64();
| * String encoded = b.encode( str );
| * String decode = b.decodeAsString( encoded );
| *
| * System.out.println( str.equals( decode ) );
| * </code></pre>
| * <p>
| * 위의 코드는 true를 리턴할 것이다.
| *
| * @author Jang-Ho Hwang, rath@xrath.com
| * @version 1.0.000, 2002/06/04
| */
| public class BASE64
| {
| static final char[] MAP =
| {
| 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H',
| 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
| 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X',
| 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f',
| 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n',
| 'o', 'p', 'q', 'r', 's', 't', 'u', 'v',
| 'w', 'x', 'y', 'z', '0', '1', '2', '3',
| '4', '5', '6', '7', '8', '9', '+', '/',
| };
|
| static final int[] REVERSE_MAP =
| {
| 0, // Padding for human readable index access
| 0, 0, 0, 0, 0, 0, 0, 0,
| 0, 0, 0, 0, 0, 0, 0, 0,
| 0, 0, 0, 0, 0, 0, 0, 0,
| 0, 0, 0, 0, 0, 0, 0, 0,
| 0, 0, 0, 0, 0, 0, 0, 0,
| 0, 0, 62, 0, 0, 0, 63, 52,
| 53, 54, 55, 56, 57, 58, 59, 60,
| 61, 0, 0, 0, 0, 0, 0, 0,
| 0, 1, 2, 3, 4, 5, 6, 7,
| 8, 9, 10, 11, 12, 13, 14, 15,
| 16, 17, 18, 19, 20, 21, 22, 23,
| 24, 25, 0, 0, 0, 0, 0, 0,
| 26, 27, 28, 29, 30, 31, 32, 33,
| 34, 35, 36, 37, 38, 39, 40, 41,
| 42, 43, 44, 45, 46, 47, 48, 49,
| 50, 51,
| };
|
| private boolean hasCRLF = true;
|
| public BASE64()
| {
| this( true );
| }
|
| public BASE64( boolean hasCRLF )
| {
| setCRLF( hasCRLF );
| }
|
| public void setCRLF( boolean hasCRLF )
| {
| this.hasCRLF = hasCRLF;
| }
|
| public boolean hasCRLF()
| {
| return this.hasCRLF;
| }
|
| /**
| * BASE64 로 인코딩된 문자열을 decode 한다.
| * 만약 올바르지 않은 BASE64 라도, 되는대로 계속 디코딩하게 된다.
| * <p>
| * 만약 byte[] 리턴되는 것이 귀찮을 경우 decodeAsString 메소드를
| * 사용하도록 하라.
| */
| public byte[] decode( String str )
| {
| ByteArrayOutputStream bos = new ByteArrayOutputStream(str.length());
| try
| {
| for(int i=0, len=str.length(); i<len; i++)
| {
| char c = str.charAt(i);
| if( c=='\r' || c=='\n' ) continue;
| int v0 = REVERSE_MAP[ str.charAt(i++) ];
| int v1 = REVERSE_MAP[ str.charAt(i++) ];
| int v2 = REVERSE_MAP[ str.charAt(i++) ];
| int v3 = REVERSE_MAP[ str.charAt(i) ];
| int v = (v0 << 18) | (v1 << 12) | (v2 << 6) | (v3 << 0);
| bos.write( (v >> 16) & 0xff );
| bos.write( (v >> 8) & 0xff );
| bos.write( (v >> 0) & 0xff );
| }
| }
| catch( IndexOutOfBoundsException e ) {}
| return bos.toByteArray();
| }
|
| /**
| * BASE64로 encode된 주어진 str 문자열을 decode 한 후,
| * 시스템 default encoding 으로 문자열로 생성해준다.
| * <p>
| * 이 메소드는 내부적으로 decode 메소드를 직접 호출한다.
| */
| public String decodeAsString( String str )
| {
| return new String( decode(str) );
| }
|
| /**
| * 주어진 문자열을 시스템 default encoding으로 byte[] 로 변환 후,
| * BASE64 로 인코딩한다.
| */
| public String encode( String str )
| {
| return encode( str.getBytes() );
| }
|
| /**
| * 주어진 byte[] 를 BASE64 로 인코딩한다.
| */
| public String encode( byte[] b )
| {
| StringBuffer sb = new StringBuffer(b.length);
| int padCount = 0;
| ByteArrayInputStream bis = new ByteArrayInputStream( b );
| for(int i=0; i<b.length; i+=3)
| {
| int v0 = bis.read();
| int v1 = bis.read();
| int v2 = bis.read();
| if( v1==-1 ) { v1 = 0; padCount = 2; }
| else
| if( v2==-1 ) { v2 = 0; padCount = 1; }
| int v =
| ((v0<<16) & 0x00FF0000) |
| ((v1<< 8) & 0x0000FF00) |
| ((v2<< 0) & 0x000000FF);
| sb.append( MAP[(v>>18) & 0x3f] );
| sb.append( MAP[(v>>12) & 0x3f] );
| sb.append( MAP[(v>> 6) & 0x3f] );
| sb.append( MAP[(v>> 0) & 0x3f] );
|
| if( ((i+3)%57)==0 && hasCRLF )
| sb.append( '\n' );
| }
| for(int i=padCount, last=sb.length(); i>0; i--)
| sb.setCharAt( last-i, '=' );
| if( hasCRLF )
| sb.append( '\n' );
| return sb.toString();
| }
| }
|
|
