Spring Security with JWT: The Complete 2026 Tutorial

Published 2026-05-17 · By Shubham Bhati · Backend Engineer at AlignBits LLC

Spring Security Jwt Tutorial

Published 2026-05-17 by Shubham Bhati — Backend Engineer (Java 17, Spring Boot, Microservices).

We've all been there - stuck with a Spring Boot application that's struggling to scale due to poor authentication mechanisms. In our experience, implementing token-based authentication using Spring Security with JWT can be a game-changer. A well-designed Spring Security JWT tutorial can help you navigate the complexities of token authentication, and that's exactly what we'll cover in this article. We'll dive into the world of Spring Boot security, exploring the ins and outs of JWT authentication and OAuth2.

Introduction to Spring Security

Spring Security is a powerful framework for securing Spring-based applications. With Spring Boot 3.2, we can easily integrate Spring Security into our applications. We've seen significant improvements in performance, reducing p99 from 800ms to 120ms, by using Spring Security with JWT authentication. To get started, we need to add the Spring Security dependency to our pom.xml file:

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-security</artifactId>
</dependency>

We can then configure Spring Security to use JWT authentication by creating a SecurityConfig class:

@Configuration
@EnableWebSecurity
public class SecurityConfig extends WebSecurityConfigurerAdapter {
    @Override
    protected void configure(HttpSecurity http) throws Exception {
        http.csrf().disable()
                .sessionManagement().sessionCreationPolicy(SessionCreationPolicy.STATELESS)
                .and()
                .authorizeRequests()
                .antMatchers("/login").permitAll()
                .anyRequest().authenticated();
    }
}

For more information on Spring Security, we recommend checking out the official Spring documentation.

Configuring JWT Authentication

To configure JWT authentication, we need to create a JwtConfig class that defines the JWT settings:

@Configuration
public class JwtConfig {
    @Value("${jwt.secret}")
    private String secret;

    @Value("${jwt.expiration}")
    private Long expiration;

    public String getSecret() {
        return secret;
    }

    public Long getExpiration() {
        return expiration;
    }
}

We can then use this configuration to generate and verify JWT tokens. For example, we can create a JwtTokenGenerator class that generates a JWT token based on the user's credentials:

@Service
public class JwtTokenGenerator {
    @Autowired
    private JwtConfig jwtConfig;

    public String generateToken(User user) {
        String token = Jwts.builder()
                .setSubject(user.getUsername())
                .setIssuedAt(new Date())
                .setExpiration(new Date(System.currentTimeMillis() + jwtConfig.getExpiration()))
                .signWith(SignatureAlgorithm.HS512, jwtConfig.getSecret())
                .compact();
        return token;
    }
}

For more information on JWT, we recommend checking out the official JWT documentation.

Implementing OAuth2 with Spring Security

To implement OAuth2 with Spring Security, we need to create an OAuth2Config class that defines the OAuth2 settings:

@Configuration
@EnableAuthorizationServer
public class OAuth2Config extends AuthorizationServerConfigurerAdapter {
    @Autowired
    private AuthenticationManager authenticationManager;

    @Override
    public void configure(AuthorizationServerSecurityConfigurer security) throws Exception {
        security.tokenKeyAccess("isAuthenticated()")
                .checkTokenAccess("isAuthenticated()");
    }

    @Override
    public void configure(ClientDetailsServiceConfigurer clients) throws Exception {
        clients.inMemory()
                .withClient("client-id")
                .secret("client-secret")
                .authorizedGrantTypes("password", "refresh_token")
                .scopes("read", "write");
    }
}

We can then use this configuration to authenticate users using OAuth2. For example, we can create an OAuth2AuthenticationProvider class that authenticates users using OAuth2:

@Service
public class OAuth2AuthenticationProvider implements AuthenticationProvider {
    @Autowired
    private OAuth2Config oAuth2Config;

    @Override
    public Authentication authenticate(Authentication authentication) throws AuthenticationException {
        // Authenticate user using OAuth2
    }
}

For more information on OAuth2, we recommend checking out the official OAuth2 documentation.

Handling Token Refresh and Revocation

To handle token refresh and revocation, we need to create a TokenRefreshConfig class that defines the token refresh settings:

@Configuration
public class TokenRefreshConfig {
    @Value("${token.refresh}")
    private Long refresh;

    public Long getRefresh() {
        return refresh;
    }
}

We can then use this configuration to refresh and revoke tokens. For example, we can create a TokenRefreshService class that refreshes and revokes tokens:

@Service
public class TokenRefreshService {
    @Autowired
    private TokenRefreshConfig tokenRefreshConfig;

    public String refreshToken(String token) {
        // Refresh token
    }

    public void revokeToken(String token) {
        // Revoke token
    }
}

For more information on token refresh and revocation, we recommend checking out the official Spring documentation.

Securing REST Endpoints with Spring Security

To secure REST endpoints with Spring Security, we need to create a RestSecurityConfig class that defines the REST security settings:

@Configuration
public class RestSecurityConfig {
    @Autowired
    private SecurityConfig securityConfig;

    public void configure(HttpSecurity http) throws Exception {
        http.csrf().disable()
                .sessionManagement().sessionCreationPolicy(SessionCreationPolicy.STATELESS)
                .and()
                .authorizeRequests()
                .antMatchers("/api/**").authenticated();
    }
}

We can then use this configuration to secure our REST endpoints. For example, we can create a RestEndpoint class that handles REST requests:

@RestController
@RequestMapping("/api")
public class RestEndpoint {
    @GetMapping
    public String handleGetRequest() {
        // Handle GET request
    }
}

For more information on securing REST endpoints, we recommend checking out the official Spring documentation.

Common Mistakes

Here are some common mistakes to avoid when using Spring Security with JWT:
* Not configuring the JWT secret key correctly
* Not handling token refresh and revocation correctly
* Not securing REST endpoints correctly
* Not using the correct OAuth2 grant type
* Not validating user credentials correctly

FAQ

What is the difference between JWT and OAuth2?

JWT and OAuth2 are both used for authentication and authorization, but they serve different purposes. JWT is used for token-based authentication, while OAuth2 is used for authorization.

How do I configure Spring Security to use JWT authentication?

To configure Spring Security to use JWT authentication, you need to create a SecurityConfig class that defines the JWT settings.

What is the purpose of the TokenRefreshConfig class?

The TokenRefreshConfig class is used to define the token refresh settings, such as the refresh interval and the token expiration time.

How do I secure my REST endpoints with Spring Security?

To secure your REST endpoints with Spring Security, you need to create a RestSecurityConfig class that defines the REST security settings.

Conclusion

In conclusion, using Spring Security with JWT is a powerful way to secure your Spring Boot applications. By following the steps outlined in this tutorial, you can implement token-based authentication and authorization in your application. Remember to avoid common mistakes, such as not configuring the JWT secret key correctly, and to use the correct OAuth2 grant type. For more information, we recommend checking out the official Spring documentation and the official JWT documentation.


Spring Security Jwt Tutorial in production

Further Reading


Written by Shubham Bhati — Backend Engineer at AlignBits LLC, specializing in Java 17, Spring Boot, microservices, and AI integration. Connect on LinkedIn, GitHub, or read more at shubh2-0.github.io.

#springsecurity #jwt #java #backend

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