How can I implement authentication in Java microservices?

How can I implement authentication in Java microservices?

You can implement authentication in Java microservices using OAuth2 or JWT. Would you like a detailed explanation of either?

Yes, please explain how to use JWT for authentication.

To use JWT, first, you need to create a token when a user logs in. This token is then sent with each request to authenticate the user.

What libraries can I use to handle JWT in Java?

You can use libraries like jjwt or Java JWT. They provide easy methods to create and verify tokens.

Can you show me a code example?

Sure! Here's a simple example using jjwt:

String jwt = Jwts.builder()
    .setSubject("[email protected]")
    .setExpiration(new Date(System.currentTimeMillis() + 86400000))
    .signWith(SignatureAlgorithm.HS512, "secretkey")
    .compact();