Java Built-In Implementation of Base64

Data Encoding Tutorials - Herong's Tutorial Examples

∟Java Built-In Implementation of Base64

This section provides a test program for the default Java implementation of the Base64 encoding algorithm java.util.Base64.Encoder.encode() and java.util.Base64.Decoder.decode() methods.

The Base64 encoding algorithm bas been implemented in Java language as 2 built-in methods since Java 8:

java.util.Base64.Encoder.encode() - Encodes data with the Base64 algorithm from byte[] to byte[].
java.util.Base64.Decoder.decode() - Decodes data with the Base64 algorithm from byte[] to byte[].

To test these built-in functions, I wrote this simple testing program:

/* Base64EncoderTest.java
 * Copyright (c) 2002 HerongYang.com. All Rights Reserved.
 */
import java.io.*;
import java.util.Base64;
class Base64EncoderTest {
  public static void main(String[] args) {
    String theInput = null;
    String theExpected = null; 
    
    System.out.println("Test 1:");
    theInput = "A";
    theExpected = "QQ==";
    test(theInput, theExpected);
    
    System.out.println("Test 2:");
    theInput = "AB";
    theExpected = "QUI=";
    test(theInput, theExpected);

    System.out.println("Test 3:");
    theInput = "ABC";
    theExpected = "QUJD";
    test(theInput, theExpected);
       
    System.out.println("Test 4:");
    theInput = "The quick brown fox jumps over the lazy dog.";
    theExpected = 
      "VGhlIHF1aWNrIGJyb3duIGZveCBqdW1wcyBvdmVyIHRoZSBsYXp5IGRvZy4=";
    test(theInput, theExpected);
  }

  private static void test(String theInput, String theExpected) { 
    
    byte[] inputBytes = theInput.getBytes();
    Base64.Encoder encoder = Base64.getEncoder();
    byte[] encodedBytes = encoder.encode(inputBytes);
    
    Base64.Decoder decoder = Base64.getDecoder();
    byte[] decodedBytes = decoder.decode(encodedBytes);
    
    System.out.println("   Input   : "+theInput);
    System.out.println("   Encoded : "+new String(encodedBytes));
    System.out.println("   Expected: "+theExpected);
    System.out.println("   Decoded : "+new String(decodedBytes));
  }
}

Here is the test result:

herong> java Base64EncoderTest.java

Test 1:
   Input   : A
   Encoded : QQ==
   Expected: QQ==
   Decoded : A
Test 2:
   Input   : AB
   Encoded : QUI=
   Expected: QUI=
   Decoded : AB
Test 3:
   Input   : ABC
   Encoded : QUJD
   Expected: QUJD
   Decoded : ABC
Test 4:
   Input   : The quick brown fox jumps over the lazy dog.
   Encoded : VGhlIHF1aWNrIGJyb3duIGZveCBqdW1wcyBvdmVyIHRoZSBsYXp5IGRvZy4=
   Expected: VGhlIHF1aWNrIGJyb3duIGZveCBqdW1wcyBvdmVyIHRoZSBsYXp5IGRvZy4=
   Decoded : The quick brown fox jumps over the lazy dog.