The method: javax.xml.bind.DatatypeConverter#printBase64Binary(byte) encodes a byte into a Base64 encoded string.
To encode a String with JDK 1.6+ use the static method
String encodedDuke = DatatypeConverter.printBase64Binary("duke".getBytes("UTF-8"));
Java 8 comes with the java.util.Base64 class entirely dedicated to Basic, URL, Filenames and MIMEs encoding and decoding.
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