The use of the Java BASE64 algorithm

Base64 is a common network encryption algorithm, and BASE64 encoding can be used to pass longer identity information in an HTTP environment. See Base64 Introduction

1 Customizing the Base64 algorithm

Base64encrypt.java

 Public classBase64encrypt {Private StaticFinal String CODES ="abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz0123456789+/="; //Base64 Decryption    Private Static byte[] Base64decode (String input) {if(Input.length ()%4!=0) {            Throw NewIllegalArgumentException ("Invalid Base64 Input"); }        byteDecoded[] =New byte[((Input.length () *3) /4)                -(Input.indexof ('=') >0? (Input.length ()-Input.indexof ('=')) :0)]; Char[] Inchars =Input.tochararray (); intj =0; intB[] =New int[4];  for(inti =0; i < inchars.length; i + =4) {            //This could is made faster (but more complicated) by precomputing//these index locations.b[0] =Codes.indexof (Inchars[i]); b[1] = Codes.indexof (inchars[i +1]); b[2] = Codes.indexof (inchars[i +2]); b[3] = Codes.indexof (inchars[i +3]); Decoded[j++] = (byte) ((b[0] <<2) | (b[1] >>4)); if(b[2] < -) {decoded[j++] = (byte) ((b[1] <<4) | (b[2] >>2)); if(b[3] < -) {decoded[j++] = (byte) ((b[2] <<6) | b[3]); }            }        }        returnDecoded; }    //Base64 Encryption    Private StaticString Base64Encode (byte[]inch) {StringBuilder out=NewStringBuilder ((inch. length *4) /3); intb;  for(inti =0; I <inch. length; i + =3) {b= (inch[I] &0xFC) >>2;  out. Append (Codes.charat (b)); b= (inch[I] &0x03) <<4; if(i +1<inch. Length) {b|= (inch[i +1] &0xF0) >>4;  out. Append (Codes.charat (b)); b= (inch[i +1] &0x0F) <<2; if(i +2<inch. Length) {b|= (inch[i +2] &0xC0) >>6;  out. Append (Codes.charat (b)); b=inch[i +2] &0x3F;  out. Append (Codes.charat (b)); } Else {                     out. Append (Codes.charat (b));  out. Append ('='); }            } Else {                 out. Append (Codes.charat (b));  out. Append ("=="); }        }        return  out. toString (); }

Test code:

     Public Static voidMain (string[] args) {String input="we are a team."; String encode=Base64Encode (Input.getbytes ()); System. out. println ("encode:"+encode); String Decode=NewString (Base64decode (encode)); System. out. println ("Decode:"+decode); }

The Base64 algorithm of 2 Bcprov

Introduction of Bcprov-jdk15on-154.jar, providing support for Base64 algorithms

Bcprov-jdk15on-154.jar Address: https://commons.apache.org/proper/commons-codec/download_codec.cgi

Test code:

String input ="we are a team."; byte[] Encodebytes =Org.bouncycastle.util.encoders.Base64.encode (Input.getbytes ()); System. out. println ("encode:"+NewString (encodebytes)); byte[] Decodebytes =Org.bouncycastle.util.encoders.Base64.decode (encodebytes); System. out. println ("Decode:"+NewString (decodebytes));

The use of the Java BASE64 algorithm