Decoding a Base64 string in Java
JavaBase64Java Problem Overview
I'm trying to decode a simple Base64 string, but am unable to do so. I'm currently using the org.apache.commons.codec.binary.Base64 package.
The test string I'm using is: abcdefg, encoded using PHP YWJjZGVmZw==.
This is the code I'm currently using:
Base64 decoder = new Base64();
byte[] decodedBytes = decoder.decode("YWJjZGVmZw==");
System.out.println(new String(decodedBytes) + "\n") ;
The above code does not throw an error, but instead doesn't output the decoded string as expected.
Java Solutions
Solution 1 - Java
Modify the package you're using:
import org.apache.commons.codec.binary.Base64;
And then use it like this:
byte[] decoded = Base64.decodeBase64("YWJjZGVmZw==");
System.out.println(new String(decoded, "UTF-8") + "\n");
Solution 2 - Java
The following should work with the latest version of Apache common codec
byte[] decodedBytes = Base64.getDecoder().decode("YWJjZGVmZw==");
System.out.println(new String(decodedBytes));
and for encoding
byte[] encodedBytes = Base64.getEncoder().encode(decodedBytes);
System.out.println(new String(encodedBytes));
Solution 3 - Java
If you don't want to use apache, you can use Java8:
byte[] decodedBytes = Base64.getDecoder().decode("YWJjZGVmZw==");
System.out.println(new String(decodedBytes) + "\n");
Solution 4 - Java
Commonly base64 it is used for images. if you like to decode an image (jpg in this example with org.apache.commons.codec.binary.Base64 package):
byte[] decoded = Base64.decodeBase64(imageJpgInBase64);
FileOutputStream fos = null;
fos = new FileOutputStream("C:\\output\\image.jpg");
fos.write(decoded);
fos.close();