Encoding as Base64 in Java

Question

I need to encode some data in the Base64 encoding in Java. How do I do that? What is the name of the class that provides a Base64 encoder?

---

I tried to use the sun.misc.BASE64Encoder class, without success. I have the following line of Java 7 code:

wr.write(new sun.misc.BASE64Encoder().encode(buf)); 

I'm using Eclipse. Eclipse marks this line as an error. I imported the required libraries:

import sun.misc.BASE64Encoder; import sun.misc.BASE64Decoder; 

But again, both of them are shown as errors. I found a similar post here.

I used Apache Commons as the solution suggested by including:

import org.apache.commons.*; 

and importing the JAR files downloaded from: http://commons.apache.org/codec/

But the problem still exists. Eclipse still shows the errors previously mentioned. What should I do?

Answer 1

You need to change the import of your class:

import org.apache.commons.codec.binary.Base64; 

And then change your class to use the Base64 class.

Here's some example code:

byte[] encodedBytes = Base64.encodeBase64("Test".getBytes()); System.out.println("encodedBytes " + new String(encodedBytes)); byte[] decodedBytes = Base64.decodeBase64(encodedBytes); System.out.println("decodedBytes " + new String(decodedBytes)); 

Then read why you shouldn't use sun.* packages.

---

Update (2016-12-16)

You can now use java.util.Base64 with Java 8. First, import it as you normally do:

import java.util.Base64; 

Then use the Base64 static methods as follows:

byte[] encodedBytes = Base64.getEncoder().encode("Test".getBytes()); System.out.println("encodedBytes " + new String(encodedBytes)); byte[] decodedBytes = Base64.getDecoder().decode(encodedBytes); System.out.println("decodedBytes " + new String(decodedBytes)); 

If you directly want to encode string and get the result as encoded string, you can use this:

String encodeBytes = Base64.getEncoder().encodeToString((userName + ":" + password).getBytes()); 

See Java documentation for Base64 for more.