Program Description
Base64 is a freeware way of encoding 8-bit characters using only ASCII printable characters similar to UUENCODE. UUENCODE embeds a filename where BASE64 does not. You will see BASE64 used in encoding digital certificates, in encoding user:password string in an Authorization: header for HTTP. The spec is described in RFC 2045.
Don't confuse Base64 with x-www-form-urlencoded which is handled by java.net.URLEncoder.encode/decode or Base64u.
Base64 armouring uses only the characters A-Z a-z 0-9 +/=. This makes it suitable for encoding binary data as SQL strings, that will work no matter what the encoding. Unfortunately + / and = all have special meaning in URLs.
Base64u gets around this problem. It is a variant on Base64 that uses - _ and * in preference to + / and =, so that it can be used in URLEncoded contexts with or without URLEncoding.
Use base64 like this:
// Base64 armouring import com.mindprod.base64.Base64; ... // sample byte array to encode byte[] toSend = { (byte)0xfc, (byte)0x0f, (byte)0xc0};
// create encoder object Base64 base64 = new Base64(); base64.setLineLength( 72 ); // default
// encoding a byte[] String send = base64.encoder( toSend );
// decoding a byte[] byte[] reconstituted = base64.decoder( sent );
use Base64u the same way:
// Base64u armouring import com.mindprod.base64.Base64u; ... // sample byte array to encode byte[] toSend = { (byte)0xfc, (byte)0x0f, (byte)0xc0};
// create encoder object Base64u base64u = new Base64u(); base64u.setLineLength( 72 ); // default
// encoding a byte[] String send = base64u.encoder( toSend );
// decoding a byte[] byte[] reconstituted = base64u.decoder( sent );
For an example that starts and ends with a String, see Example.java
to run: java.exe com.mindprod.base64.Example