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/**
The MIT License (MIT) * Copyright (c) 2016 铭飞科技(mingsoft.net)
* Permission is hereby granted, free of charge, to any person obtaining a copy of
* this software and associated documentation files (the "Software"), to deal in
* the Software without restriction, including without limitation the rights to
* use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
* the Software, and to permit persons to whom the Software is furnished to do so,
* subject to the following conditions:
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
* FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
* COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
* IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package com.mingsoft.util;
import org.apache.commons.codec.binary.Base64;
/**
* base64加密&解密通用方法
* @author 王天培QQ:78750478
* @version
* 版本号：100-000-000
* 创建日期：2012-03-15
* 历史修订：
*/
public class Base64Util {
static private final int BASELENGTH = 255;
static final private byte[] base64Alphabet = new byte[BASELENGTH];
static private final int EIGHTBIT = 8;
static private final boolean fDebug = false;
static private final int FOURBYTE = 4;
static private final int LOOKUPLENGTH = 64;
static final private char[] lookUpBase64Alphabet = new char[LOOKUPLENGTH];
static private final char PAD = '=';
static private final int SIGN = -128;
@SuppressWarnings("unused")
static private final int SIXBIT = 6;
static private final int SIXTEENBIT = 16;
static private final int TWENTYFOURBITGROUP = 24;
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] = (char) ('A' + i);
for (int i = 26, j = 0; i <= 51; i++, j++)
lookUpBase64Alphabet[i] = (char) ('a' + j);
for (int i = 52, j = 0; i <= 61; i++, j++)
lookUpBase64Alphabet[i] = (char) ('0' + j);
lookUpBase64Alphabet[62] = (char) '+';
lookUpBase64Alphabet[63] = (char) '/';
}
/**
* 解码base64数据为octects
* (Decodes Base64 data into octects)
*
* @param encoded 包含Base64编码数据
* (containing Base64 data)
* @return Array 已解码的字节型数组
* (containind decoded data)
*/
@SuppressWarnings("unused")
public static byte[] decode(String encoded) {
if (encoded == null)
return null;
char[] base64Data = encoded.toCharArray();
// remove white spaces
int len = removeWhiteSpace(base64Data);
if (len % FOURBYTE != 0) {
return null;// should be divisible by four
}
int numberQuadruple = (len / FOURBYTE);
if (numberQuadruple == 0)
return new byte[0];
byte decodedData[] = null;
byte b1 = 0, b2 = 0, b3 = 0, b4 = 0, marker0 = 0, marker1 = 0;
char d1 = 0, d2 = 0, d3 = 0, d4 = 0;
int i = 0;
int encodedIndex = 0;
int dataIndex = 0;
decodedData = new byte[(numberQuadruple) * 3];
for (; i < numberQuadruple - 1; i++) {
if (!isData((d1 = base64Data[dataIndex++])) || !isData((d2 = base64Data[dataIndex++])) || !isData((d3 = base64Data[dataIndex++])) || !isData((d4 = base64Data[dataIndex++])))
return null;// if found "no data" just return null
b1 = base64Alphabet[d1];
b2 = base64Alphabet[d2];
b3 = base64Alphabet[d3];
b4 = base64Alphabet[d4];
decodedData[encodedIndex++] = (byte) (b1 << 2 | b2 >> 4);
decodedData[encodedIndex++] = (byte) (((b2 & 0xf) << 4) | ((b3 >> 2) & 0xf));
decodedData[encodedIndex++] = (byte) (b3 << 6 | b4);
}
if (!isData((d1 = base64Data[dataIndex++])) || !isData((d2 = base64Data[dataIndex++]))) {
return null;// if found "no data" just return null
}
b1 = base64Alphabet[d1];
b2 = base64Alphabet[d2];
d3 = base64Data[dataIndex++];
d4 = base64Data[dataIndex++];
if (!isData((d3)) || !isData((d4))) {// Check if they are PAD characters
if (isPad(d3) && isPad(d4)) { // Two PAD e.g. 3c[Pad][Pad]
if ((b2 & 0xf) != 0)// last 4 bits should be zero
return null;
byte[] tmp = new byte[i * 3 + 1];
System.arraycopy(decodedData, 0, tmp, 0, i * 3);
tmp[encodedIndex] = (byte) (b1 << 2 | b2 >> 4);
return tmp;
} else if (!isPad(d3) && isPad(d4)) { // One PAD e.g. 3cQ[Pad]
b3 = base64Alphabet[d3];
if ((b3 & 0x3) != 0)// last 2 bits should be zero
return null;
byte[] tmp = new byte[i * 3 + 2];
System.arraycopy(decodedData, 0, tmp, 0, i * 3);
tmp[encodedIndex++] = (byte) (b1 << 2 | b2 >> 4);
tmp[encodedIndex] = (byte) (((b2 & 0xf) << 4) | ((b3 >> 2) & 0xf));
return tmp;
} else {
return null;// an error like "3c[Pad]r", "3cdX", "3cXd", "3cXX"
// where X is non data
}
} else { // No PAD e.g 3cQl
b3 = base64Alphabet[d3];
b4 = base64Alphabet[d4];
decodedData[encodedIndex++] = (byte) (b1 << 2 | b2 >> 4);
decodedData[encodedIndex++] = (byte) (((b2 & 0xf) << 4) | ((b3 >> 2) & 0xf));
decodedData[encodedIndex++] = (byte) (b3 << 6 | b4);
}
return decodedData;
}
/**
* 编码octects为Base64数据
* (Encodes hex octects into Base64)
*
* @param binaryData
* 二进制数据数组(Array containing binaryData)
*
* @return 编码的Base64字符串(Encoded Base64 array)
*/
public static String encode(byte[] binaryData) {
if (binaryData == null)
return null;
int lengthDataBits = binaryData.length * EIGHTBIT;
if (lengthDataBits == 0) {
return "";
}
int fewerThan24bits = lengthDataBits % TWENTYFOURBITGROUP;
int numberTriplets = lengthDataBits / TWENTYFOURBITGROUP;
int numberQuartet = fewerThan24bits != 0 ? numberTriplets + 1 : numberTriplets;
int numberLines = (numberQuartet - 1) / 19 + 1;
char encodedData[] = null;
encodedData = new char[numberQuartet * 4 + numberLines];
byte k = 0, l = 0, b1 = 0, b2 = 0, b3 = 0;
int encodedIndex = 0;
int dataIndex = 0;
int i = 0;
if (fDebug) {
System.out.println("number of triplets = " + numberTriplets);
}
for (int line = 0; line < numberLines - 1; line++) {
for (int quartet = 0; quartet < 19; quartet++) {
b1 = binaryData[dataIndex++];
b2 = binaryData[dataIndex++];
b3 = binaryData[dataIndex++];
if (fDebug) {
System.out.println("b1= " + b1 + ", b2= " + b2 + ", b3= " + b3);
}
l = (byte) (b2 & 0x0f);
k = (byte) (b1 & 0x03);
byte val1 = ((b1 & SIGN) == 0) ? (byte) (b1 >> 2) : (byte) ((b1) >> 2 ^ 0xc0);
byte val2 = ((b2 & SIGN) == 0) ? (byte) (b2 >> 4) : (byte) ((b2) >> 4 ^ 0xf0);
byte val3 = ((b3 & SIGN) == 0) ? (byte) (b3 >> 6) : (byte) ((b3) >> 6 ^ 0xfc);
if (fDebug) {
System.out.println("val2 = " + val2);
System.out.println("k4 = " + (k << 4));
System.out.println("vak = " + (val2 | (k << 4)));
}
encodedData[encodedIndex++] = lookUpBase64Alphabet[val1];
encodedData[encodedIndex++] = lookUpBase64Alphabet[val2 | (k << 4)];
encodedData[encodedIndex++] = lookUpBase64Alphabet[(l << 2) | val3];
encodedData[encodedIndex++] = lookUpBase64Alphabet[b3 & 0x3f];
i++;
}
encodedData[encodedIndex++] = 0xa;
}
for (; i < numberTriplets; i++) {
b1 = binaryData[dataIndex++];
b2 = binaryData[dataIndex++];
b3 = binaryData[dataIndex++];
if (fDebug) {
System.out.println("b1= " + b1 + ", b2= " + b2 + ", b3= " + b3);
}
l = (byte) (b2 & 0x0f);
k = (byte) (b1 & 0x03);
byte val1 = ((b1 & SIGN) == 0) ? (byte) (b1 >> 2) : (byte) ((b1) >> 2 ^ 0xc0);
byte val2 = ((b2 & SIGN) == 0) ? (byte) (b2 >> 4) : (byte) ((b2) >> 4 ^ 0xf0);
byte val3 = ((b3 & SIGN) == 0) ? (byte) (b3 >> 6) : (byte) ((b3) >> 6 ^ 0xfc);
if (fDebug) {
System.out.println("val2 = " + val2);
System.out.println("k4 = " + (k << 4));
System.out.println("vak = " + (val2 | (k << 4)));
}
encodedData[encodedIndex++] = lookUpBase64Alphabet[val1];
encodedData[encodedIndex++] = lookUpBase64Alphabet[val2 | (k << 4)];
encodedData[encodedIndex++] = lookUpBase64Alphabet[(l << 2) | val3];
encodedData[encodedIndex++] = lookUpBase64Alphabet[b3 & 0x3f];
}
// form integral number of 6-bit groups
if (fewerThan24bits == EIGHTBIT) {
b1 = binaryData[dataIndex];
k = (byte) (b1 & 0x03);
if (fDebug) {
System.out.println("b1=" + b1);
System.out.println("b1<<2 = " + (b1 >> 2));
}
byte val1 = ((b1 & SIGN) == 0) ? (byte) (b1 >> 2) : (byte) ((b1) >> 2 ^ 0xc0);
encodedData[encodedIndex++] = lookUpBase64Alphabet[val1];
encodedData[encodedIndex++] = lookUpBase64Alphabet[k << 4];
encodedData[encodedIndex++] = PAD;
encodedData[encodedIndex++] = PAD;
} else if (fewerThan24bits == SIXTEENBIT) {
b1 = binaryData[dataIndex];
b2 = binaryData[dataIndex + 1];
l = (byte) (b2 & 0x0f);
k = (byte) (b1 & 0x03);
byte val1 = ((b1 & SIGN) == 0) ? (byte) (b1 >> 2) : (byte) ((b1) >> 2 ^ 0xc0);
byte val2 = ((b2 & SIGN) == 0) ? (byte) (b2 >> 4) : (byte) ((b2) >> 4 ^ 0xf0);
encodedData[encodedIndex++] = lookUpBase64Alphabet[val1];
encodedData[encodedIndex++] = lookUpBase64Alphabet[val2 | (k << 4)];
encodedData[encodedIndex++] = lookUpBase64Alphabet[l << 2];
encodedData[encodedIndex++] = PAD;
}
encodedData[encodedIndex] = 0xa;
return new String(encodedData);
}
/**
* base64位加密
*
* @param bytes 字符串子节数组
* @return 返回加密后的字符串
*/
public static String getBASE64(byte[] bytes) {
byte[] s = null;
if (bytes != null) {
s = Base64.encodeBase64(bytes);
}
return new String(s);
}
/**
* base64位解密
*
* @param str 需要解密的base64为字符串
* @return 返回解密后的字符串字节数组
*/
public static byte[] getFromBASE64(String str) {
byte[] b = null;
if (str != null) {
try {
b = Base64.encodeBase64(str.getBytes());
return b;
} catch (Exception e) {
e.printStackTrace();
}
}
return b;
}
/**
* 判断是否是base64加密数据
* @param octect 加密的字符
* @return 如果是加密字符，则返回true，否则返回false
*/
protected static boolean isBase64(char octect) {
return (isWhiteSpace(octect) || isPad(octect) || isData(octect));
}
/**
* 判断是否是-1
* @param octect 加密的字符
* @return 如果是-1，则返回true，否则返回false
*/
protected static boolean isData(char octect) {
return (base64Alphabet[octect] != -1);
}
/**
* 判断是否是等号
* @param octect
* @return 如果是等号，则返回true，否则返回false
*/
protected static boolean isPad(char octect) {
return (octect == PAD);
}
/**
* 判断是否是空格
* @param octect
* @return 如果是空格，则返回true，否则返回false
*/
protected static boolean isWhiteSpace(char octect) {
return (octect == 0x20 || octect == 0xd || octect == 0xa || octect == 0x9);
}
/**
* 加密测试方法
* @param args 主方法形参
*/
public static void main(String[] args) {
String str = "asfd";
System.out.println(Base64Util.getBASE64(str.getBytes()));
}
/**
* remove WhiteSpace from MIME containing encoded Base64 data.
*
* @param data
* the byte array of base64 data (with WS)
* @return the new length
*/
protected static int removeWhiteSpace(char[] data) {
if (data == null)
return 0;
// count characters that's not whitespace
int newSize = 0;
int len = data.length;
for (int i = 0; i < len; i++) {
if (!isWhiteSpace(data[i]))
data[newSize++] = data[i];
}
return newSize;
}
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