In this source code example, we show you how to encode and decode(Base64) any arbitrary text in Java using the Base64 API that was introduced in Java 8.

Base64 is a binary-to-text encoding scheme that represents binary data in a printable ASCII string format.

Java Base64 Encode and Decode Example

import java.io.UnsupportedEncodingException;
import java.nio.charset.StandardCharsets;
import java.util.Base64;

class Base64DecodeExample {

    private static String base64Decode(String value) {
        try {
            byte[] decodedValue = Base64.getDecoder().decode(value);
            return new String(decodedValue, StandardCharsets.UTF_8.toString());
        } catch(UnsupportedEncodingException ex) {
            throw new RuntimeException(ex);
        }
    }

    private static String base64Encode(String value) {
        try {
            return Base64.getEncoder()
                    .encodeToString(value.getBytes(StandardCharsets.UTF_8.toString()));
        } catch(UnsupportedEncodingException ex) {
            throw new RuntimeException(ex);
        }
    }

    public static void main(String[] args) {
        String data = "https://www.sourcecodeexamples.net";

        String encodedData = base64Encode(data);

        System.out.println("encodedData -> " + encodedData);

        String decodedData = base64Decode(encodedData);

        System.out.println("decodedData -> " + decodedData);
    }
}

Output:

encodedData -> aHR0cHM6Ly93d3cuc291cmNlY29kZWV4YW1wbGVzLm5ldA==
decodedData -> https://www.sourcecodeexamples.net

References

https://docs.oracle.com/javase/8/docs/api/java/util/Base64.html