What is Spring Security?

Question

Accepted Answer

**Spring Security** — authentication and authorization framework for Spring applications.

```java
@Configuration
@EnableWebSecurity
public class SecurityConfig {
    @Bean
    public SecurityFilterChain filterChain(HttpSecurity http) throws Exception {
        http
            .authorizeHttpRequests(auth -> auth
                .requestMatchers("/public/**").permitAll()
                .requestMatchers("/admin/**").hasRole("ADMIN")
                .anyRequest().authenticated()
            )
            .oauth2Login(oauth -> oauth
                .userInfoEndpoint(info -> info
                    .userService(oauth2UserService)
                )
            )
            .csrf(csrf -> csrf.disable());
        return http.build();
    }
}
```

**Features:**
- Authentication (form, OAuth2, JWT, SAML).
- Authorization (role, method-level).
- CSRF protection.
- Session management.
- Security headers.

Java: What is Spring Security?