????????java???????У?
????1??BASE64 ???????????????????????????
????2??MD5(Message Digest algorithm 5?????????)
????3??SHA(Secure Hash Algorithm??????????)
????4??HMAC(Hash Message Authentication Code??????????????)
????1. BASE64
????Base64????????????????????8Bit??????????????????????RFC2045??RFC2049????????MIME??????淶??Base64???????????HTTP?????′?????????????????磬??Java Persistence??Hibernate?У???????Base64??????????????????????128-bit??UUID?????????????????????HTTP?????HTTP GET URL?е?????????????????????У???????????????????????????????URL???????????????е???????????????Base64??????в?????????????????????????????????????????
????java??????
package com.cn.???????;
import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;
/*
BASE64???????????????????????.
BASE64Encoder??BASE64Decoder?????JDK??????????????JDK???????????????????API??鯔????
JRE ?? sun ?? com.sun ???????????δ?????????????????? java?? javax ????????????е???????????????й??
?????????????????
BASE64 ???????????????????????????
?????BASE64Encoder??BASE64Decoder??????????????????????????????ɡ?
???BASE?????????????λ????8??????????????λ????=???????
BASE64
????RFC2045????壬Base64?????????Base64??????????????????????????е?8λ?????????????????????????????
??The Base64 Content-Transfer-Encoding is designed to represent arbitrary sequences of octets in a form that need not be humanly readable.??
???????????http????????http???????????????????????????????????BASE64??????
*/
public class BASE64 {
/**
* BASE64????
*
* @param key
* @return
* @throws Exception
*/
public static byte[] decryptBASE64(String key) throws Exception {
return (new BASE64Decoder()).decodeBuffer(key);
}
/**
* BASE64????
*
* @param key
* @return
* @throws Exception
*/
public static String encryptBASE64(byte[] key) throws Exception {
return (new BASE64Encoder()).encodeBuffer(key);
}
public static void main(String[] args) {
String str="12345678";
try {
String result1= BASE64.encryptBASE64(str.getBytes());
System.out.println("result1=====????????=========="+result1);
byte result2[]= BASE64.decryptBASE64(result1);
String str2=new String(result2);
System.out.println("str2========????????========"+str2);
} catch (Exception e) {
e.printStackTrace();
}
}
}
????2. MD5
????MD5??Message-Digest Algorithm 5?????-????5????????????????????????????????????????????????????????????????????????????????????MD5????????????紡?????????????????????????????????????MD5???????MD2??MD3??MD4?????????????????????????????У?顣У?飿??????????????MD5?????????MD5???????????ISOУ?飬????MD5У?顣????????????ISO????MD5?????MD5????????????linux-ISO?????????????????????????MD5??????????????????????μ??
????java???
package com.cn.???????;
import java.math.BigInteger;
import java.security.MessageDigest;
/*
MD5(Message Digest algorithm 5?????????)
??????????????????MD5??????????MD5????????????齻??BASE64??????????????????????
Digest:???
*/
public class MD5 {
public static final String KEY_MD5 = "MD5";
public static String getResult(String inputStr)
{
System.out.println("=======???????????:"+inputStr);
BigInteger bigInteger=null;
try {
MessageDigest md = MessageDigest.getInstance(KEY_MD5);
byte[] inputData = inputStr.getBytes();
md.update(inputData);
bigInteger = new BigInteger(md.digest());
} catch (Exception e) {e.printStackTrace();}
System.out.println("MD5?????:" + bigInteger.toString(16));
return bigInteger.toString(16);
}
public static void main(String args[])
{
try {
String inputStr = "??????8888888888888888888";
getResult(inputStr);
} catch (Exception e) {
e.printStackTrace();
}
}
}
????MD5?????????????
????1?????????????????????????MD5?????????????
????2????????????????????MD5????????
????3?????????????????????κθ????????????1?????????????MD5????к??????
????4??????????????????????MD5??????????????????MD5??????????α?????????????????
????5??????????????????????????????????????????MD5?????????????
????MD5????????????????????????????????????????????”???”???????????????????????????????任?????????????????????????????MD5???????б???????????sha-1??RIPEMD???Haval???
????3.SHA
??????????????Secure Hash Algorithm???????????????????????Digital Signature Standard DSS?????漲??????????????Digital Signature Algorithm DSA???????????С??2^64λ???????SHA1????????160λ????????????????????????????????????????????????????????á??????????????????????????????????????????????????Σ??????С???????????????????????????????????????????????????????????????λ?????????????м????????????????????????????????????к????????????????????“???”????“??”??????????????????????????????????????????
????java????
package com.cn.???????;
import java.math.BigInteger;
import java.security.MessageDigest;
/*
SHA(Secure Hash Algorithm??????????????????????????????????????????
??????????????????????????????????SHA??MD5??????????????????
????SHA??????????????????????MD5??????*/
public class SHA {
public static final String KEY_SHA = "SHA";
public static String getResult(String inputStr)
{
BigInteger sha =null;
System.out.println("=======???????????:"+inputStr);
byte[] inputData = inputStr.getBytes();
try {
MessageDigest messageDigest = MessageDigest.getInstance(KEY_SHA);
messageDigest.update(inputData);
sha = new BigInteger(messageDigest.digest());
System.out.println("SHA?????:" + sha.toString(32));
} catch (Exception e) {e.printStackTrace();}
return sha.toString(32);
}
public static void main(String args[])
{
try {
String inputStr = "??????";
getResult(inputStr);
} catch (Exception e) {
e.printStackTrace();
}
}
}
????SHA-1??MD5????
??????????????MD4??????SHA-1??MD5????????????????????????????????????????????????????????
????l ????й???????????????????????????SHA-1????MD5????32 λ???????м??????????κ??????????????????????????????MD5??2^128?????????????????SHA-1????2^160???????????????????SHA-1????й????и????????
????l ????????????????????MD5????????????????????????SHA-1??ò????????????????
????l ?????????????????SHA-1??????????MD5????