package com.hrms.util;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.Reader;
import java.io.StringReader;
import java.security.Key;
import java.security.SecureRandom;
import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
public class EncryptUtil {
/************************************** base64加密解密 **************************************/
private static final char[] SIXTY_FOUR_CHARS = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"
.toCharArray();
private static final int[] REVERSE_MAPPING = new int[123];
static {
for (int i = 0; i < SIXTY_FOUR_CHARS.length; i++)
REVERSE_MAPPING[SIXTY_FOUR_CHARS[i]] = i + 1;
}
/**
* 使用base64对字节数组进行加密，加密成一个字符串
*
* @param input
* 待加密的字节数组
* @return 加密后的字符串
*/
public static String encryptByteBYBase64(byte[] input) {
StringBuffer result = new StringBuffer();
int outputCharCount = 0;
for (int i = 0; i < input.length; i += 3) {
int remaining = Math.min(3, input.length - i);
int oneBigNumber = (input[i] & 0xff) << 16
| (remaining <= 1 ? 0 : input[i + 1] & 0xff) << 8
| (remaining <= 2 ? 0 : input[i + 2] & 0xff);
for (int j = 0; j < 4; j++)
result
.append(remaining + 1 > j ? SIXTY_FOUR_CHARS[0x3f & oneBigNumber >> 6 * (3 - j)]
: '=');
if ((outputCharCount += 4) % 76 == 0)
result.append('\n');
}
return result.toString();
}
/**
* 用base64对字符串进行加密，解密成一个字节数组
*
* @param input
* 待解密的字符串
* @return 解密后的字节数组
*/
public static byte[] dencryptStringBYBase64(String input) {
try {
ByteArrayOutputStream out = new ByteArrayOutputStream();
StringReader in = new StringReader(input);
for (int i = 0; i < input.length(); i += 4) {
int a[] = { mapCharToInt(in), mapCharToInt(in),
mapCharToInt(in), mapCharToInt(in) };
int oneBigNumber = (a[0] & 0x3f) << 18 | (a[1] & 0x3f) << 12
| (a[2] & 0x3f) << 6 | (a[3] & 0x3f);
for (int j = 0; j < 3; j++)
if (a[j + 1] >= 0)
out.write(0xff & oneBigNumber >> 8 * (2 - j));
}
return out.toByteArray();
} catch (IOException e) {
throw new Error(e + ": " + e.getMessage());
}
}
private static int mapCharToInt(Reader input) throws IOException {
int c;
while ((c = input.read()) != -1) {
int result = REVERSE_MAPPING[c];
if (result != 0)
return result - 1;
if (c == '=')
return -1;
}
return -1;
}
/*************************************** MD5加密 ***************************************/
/**
* 使用MD5算法对字符串进行加密
*
* @param target
* 要进行加密的字符串
* @return 加密后的字符串
*/
public static String encryptStringByMD5(String target) {
byte[] source = target.getBytes();
String s = null;
// 用来将字节转换成 16 进制表示的字符
char hexDigits[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
'a', 'b', 'c', 'd', 'e', 'f' };
try {
java.security.MessageDigest md = java.security.MessageDigest
.getInstance("MD5");
md.update(source);
byte tmp[] = md.digest(); // MD5 的计算结果是一个 128 位的长整数，
// 用字节表示就是 16 个字节
char str[] = new char[16 * 2]; // 每个字节用 16 进制表示的话，使用两个字符，
// 所以表示成 16 进制需要 32 个字符
int k = 0; // 表示转换结果中对应的字符位置
for (int i = 0; i < 16; i++) { // 从第一个字节开始，对 MD5 的每一个字节
// 转换成 16 进制字符的转换
byte byte0 = tmp[i]; // 取第 i 个字节
str[k++] = hexDigits[byte0 >>> 4 & 0xf]; // 取字节中高 4 位的数字转换,
// >>> 为逻辑右移，将符号位一起右移
str[k++] = hexDigits[byte0 & 0xf]; // 取字节中低 4 位的数字转换
}
s = new String(str); // 换后的结果转换为字符串
} catch (Exception e) {
e.printStackTrace();
}
return s;
}
/************************************ DES加密解密 ************************************/
static Key key;
public static final String defaultKey = "daijj";
/**
* 根据参数生成KEY
*
* @param strKey
*/
private static void getKey(String strKey) {
try {
KeyGenerator kg = KeyGenerator.getInstance("DES");
kg.init(new SecureRandom(strKey.getBytes()));
key = kg.generateKey();
kg = null;
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* 使用DES算法对字符串进行加密，返回加密后的字符串
*
* @param strMing
* 待加密的字符串
* @param strKey
* 加密密钥
* @return 加密后的字符串
*/
public static String encryptStringByDES(String strMing, String strKey) {
getKey(strKey);
byte[] byteMi = null;
byte[] byteMing = null;
String strMi = "";
try {
byteMing = strMing.getBytes("UTF8");
byteMi = encryptByteByDES(byteMing, strKey);
strMi = encryptByteBYBase64(byteMi);
} catch (Exception e) {
e.printStackTrace();
} finally {
byteMing = null;
byteMi = null;
}
return strMi;
}
/**
* 使用DES算法对字符串进行解密，返回解密后的字符串
*
* @param strMi
* 待解密的字符串
* @param strKey
* 解密密钥
* @return 解密后的字符串
*/
public static String dencryptStringByDES(String strMi, String strKey) {
getKey(strKey);
byte[] byteMing = null;
byte[] byteMi = null;
String strMing = "";
try {
byteMi = dencryptStringBYBase64(strMi);
byteMing = dencryptByteByDES(byteMi, strKey);
strMing = new String(byteMing, "UTF8");
} catch (Exception e) {
e.printStackTrace();
} finally {
byteMing = null;
byteMi = null;
}
return strMing;
}
/**
* 使用DES算法对字节数组进行加密，返回加密后的字节数组
*
* @param byteS
* 待加密的字节数组
* @param strKey
* 加密密钥
* @return 加密后的字节数组
*/
private static byte[] encryptByteByDES(byte[] byteS, String strKey) {
getKey(strKey);
Cipher cipher;
byte[] byteFina = null;
try {
cipher = Cipher.getInstance("DES");
cipher.init(Cipher.ENCRYPT_MODE, key);
byteFina = cipher.doFinal(byteS);
} catch (Exception e) {
e.printStackTrace();
} finally {
cipher = null;
}
return byteFina;
}
/**
* 使用DES算法对字节数组进行解密，返回解密后的字节数组
*
* @param byteD
* 待解密的字节数组
* @param strKey
* 解密密钥
*
* @return 解密后的字节数组
*/
private static byte[] dencryptByteByDES(byte[] byteD, String strKey) {
getKey(strKey);
Cipher cipher;
byte[] byteFina = null;
try {
cipher = Cipher.getInstance("DES");
cipher.init(Cipher.DECRYPT_MODE, key);
byteFina = cipher.doFinal(byteD);
} catch (Exception e) {
e.printStackTrace();
} finally {
cipher = null;
}
return byteFina;
}
public static void main(String[] args) {
String ming = "dreajay";
String mi = EncryptUtil.encryptStringByDES(ming, defaultKey);
System.out.println(mi);
System.out.println(mi.length());
}
}