This is a Java configuration class for Spring Security that enables users to configure Spring Security easily without the use of XML. Create a secure config file named SecurityConfiguration.kt. Here's the code for the class:

@Configuration
@EnableWebSecurity
class SecurityConfiguration: WebSecurityConfigurerAdapter() {

    @Throws(Exception::class)
    override fun configure(auth: AuthenticationManagerBuilder?) {
        auth!!
                .inMemoryAuthentication()
                .passwordEncoder(passwordEncoder())
             // user1 as USER
                .withUser("sunnat")
                .password(passwordEncoder().encode("password"))
                .roles("USER")
                .and()

                // user2 as ADMIN
               .withUser("admin")        
               .password(passwordEncoder().encode("password"))
                .roles("ADMIN")
    }

    @Throws(Exception::class)
    override fun configure(http: HttpSecurity?) {
        http!!
                .antMatcher("/**").authorizeRequests()
                .anyRequest().authenticated()
                .and()
                .formLogin()
                .and()
                .httpBasic()
    }

    @Bean(name = [BeanIds.AUTHENTICATION_MANAGER])
    @Throws(Exception::class)
    override fun authenticationManagerBean(): AuthenticationManager {
        return super.authenticationManagerBean()
    }


    @Bean
    fun passwordEncoder(): BCryptPasswordEncoder {
        return BCryptPasswordEncoder(16)
    }
}

This is a configuration class, so you need to add the @Configuration annotation. 

This class extends WebSecurityConfigurerAdapter, and the @EnableWebSecurity annotation provides the web-based security mechanism.  

According to this code, we use two @Bean annotations in the required functions. We inject AuthenticationManager and configure it via AuthorizationServerEndpointsConfigurer. The BCryptPasswordEncoder instance is used to encode the passwords.

In configure(http: HttpSecurity?), note the following:

• antMatcher("/**").authorizeRequests() means that this HttpSecurity will only be applicable to URLs that start with /**.
• anyRequest().authenticated() utilization guarantees that any request to our application requires the client to be confirmed.
• formLogin() allows users to authenticate with form-based logins.
• httpBasic() means the user is validated with HTTP Basic authentication.

In configure(auth: AuthenticationManagerBuilder?), note the following:

• inMemoryAuthentication() includes memory confirmation to AuthenticationManagerBuilder and restores InMemoryUserDetailsManagerConfigurer to permit customization of the in-memory validation.
• passwordEncoder(passwordEncoder()) means that the password will be an encoded password.
• withUser("user") and withUser("admin") is the name of the user.
• password(passwordEncoder().encode("password")) is the encoded password.
• roles("USER") and roles("ADMIN") is the role of a user.