JSON Web Token (JWT) Explained With Java jjwt Examples
Learn how a JSON Web Token (JWT) works, create and validate one with jjwt 0.13 and nimbus-jose-jwt, and avoid the storage, key and expiry mistakes.
Java EdDSA Example: Sign and Verify With Ed25519 and Ed448
Java EdDSA example with Ed25519 and Ed448. Generate keys, sign and verify messages, save and load keys, and compare EdDSA with ECDSA, RSA and ML-DSA.
Secure Random Number Generation in Java with SecureRandom
Secure random number generation in Java with SecureRandom. Create tokens and codes, pick NativePRNG, DRBG or getInstanceStrong and avoid seeding mistakes.
InvalidKeyException: Parameters missing in Java AES (Fixed)
Fix InvalidKeyException Parameters missing by passing the IV to Cipher.init(), with AES-GCM IV storage and InvalidAlgorithmParameterException causes.
Java AES Encryption and Decryption: AES-256-GCM Example
Java AES encryption and decryption with AES-256-GCM, random IVs, key storage, PBKDF2 and HKDF keys, file encryption, tamper detection and common mistakes.
Bypass SSL Certificate Checking in Java (and Safer Fixes)
Bypass SSL certificate checking in Java only in local tests, and fix PKIX errors safely with a truststore, a trusted PEM certificate or Spring SSL bundles.
REST API Security Guide: Checklist With OWASP API Top 10
A current REST API security checklist with OAuth 2.1, JWT validation, TLS, authorization checks, input validation, rate limiting and OWASP API Top 10.
Java File Checksum: MD5 and SHA-256 Hash Examples
Java file checksum examples for MD5 and SHA-256 with MessageDigest, streaming for large files, HexFormat, Guava, Commons Codec and verifying downloads.
Java Password Hashing: MD5, SHA, PBKDF2, bcrypt and Argon2
Java password hashing done right with PBKDF2, bcrypt, scrypt and Argon2id, OWASP parameters, salts, real timings, and why MD5 and SHA-256 fail.
