The following OAuth2AuthorizationServerConfigurer will configure all the necessary filters required to run an Authorization Server:

@Configuration
@EnableAuthorizationServer
public class OAuth2AuthorizationServerConfigurer extends AuthorizationServerConfigurerAdapter {

    @Autowired
    private AuthenticationManager authenticationManagerBean;

    @Override
    public void configure(ClientDetailsServiceConfigurer clients) 
    throws Exception {
        clients.inMemory().withClient("angularjsapp").secret("
        {noop}angularjs123").authorizedGrantTypes("password").
         scopes("read,write");
    }

    @Override
    public void configure(AuthorizationServerEndpointsConfigurer 
    endpoints) throws Exception {
        endpoints.authenticationManager(authenticationManagerBean);
    }
}

The preceding configuration class extends from AuthorizationServerConfigurerAdapter and is annotated with @EnableAuthorizationServer to set up all the necessary filters. Also, in the configure(ClientDetailsServiceConfigurer clients) method, it configures in-memory OAuth2 client credentials for accessing the protected /oauth/token endpoint, and in the configure(AuthorizationServerEndpointsConfigurer endpoints) method, it configures AuthenticationManager, which is injected.