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Security Beginner

Standard Base64 encoding and decoding

Use java.util.Base64 instead of internal JDK classes or third-party codecs.

Code Comparison

✕ Internal JDK API

String encoded = new sun.misc.BASE64Encoder()
    .encode(data);

✓ Java 8+

String encoded = Base64.getEncoder()
    .encodeToString(data);

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Why the modern way wins

🛡️

Supported API

Avoids inaccessible sun.misc implementation classes.

🧩

Complete variants

Includes basic, URL-safe, and MIME encoders and decoders.

🚀

No dependency

Encoding and decoding are built into the JDK.

Old Approach

sun.misc encoder

Modern Approach

Standard Base64 API

Since JDK

Difficulty

Beginner

JDK Support

Standard Base64 encoding and decoding

Available

Widely available since JDK 8 (March 2014).

How it works

The standard Base64 API provides basic, URL-safe, and MIME encoders and decoders without relying on unsupported internal packages. Use getEncoder() and getDecoder() for standard Base64, or select the URL and MIME variants when the target format requires them.

PEM encoding/decoding

Java 8

String pem = "-----BEGIN CERTIFICATE-----\n"
    + Base64.getMimeEncoder()
        .encodeToString(
            cert.getEncoded())
    + "\n-----END CERTIFICATE-----";

Java 25 (Preview)

// Encode to PEM
String pem = PEMEncoder.of()
    .encodeToString(cert);
// Decode from PEM
var cert = PEMDecoder.of()
    .decode(pemString);

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JDK 25+ →

Date/Time Intermediate

HexFormat

Java 8

// Pad to 2 digits, uppercase
String hex = String.format(
    "%02X", byteValue);
// Parse hex string
int val = Integer.parseInt(
    "FF", 16);

Java 17+

var hex = HexFormat.of()
    .withUpperCase();
String s = hex.toHexDigits(
    byteValue);
byte[] bytes =
    hex.parseHex("48656C6C6F");

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JDK 17+ →

Strings Beginner

String chars as stream

Java 8

for (int i = 0; i < str.length(); i++) {
    char c = str.charAt(i);
    if (Character.isDigit(c)) {
        process(c);
    }
}

Java 9+

str.chars()
    .filter(Character::isDigit)
    .forEach(c -> process((char) c));

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JDK 9+ →