Spring Security Config for Form based as well as OAuth2

SecurityConfig.java

@Configuration
@EnableWebSecurity
public class SecurityConfig extends WebSecurityConfigurerAdapter {

	@Override
	protected void configure(HttpSecurity http) throws Exception {

		http.authorizeRequests().antMatchers("/login").permitAll()
		        .anyRequest().authenticated() 
		        .and().formLogin() // enable form based login
			.loginPage("/login").defaultSuccessUrl("/formLoginSuccess")
			.and().logout() // enable logout 
			.and().oauth2Login() // enable OAuth2 
			.loginPage("/login").defaultSuccessUrl("/oauth2LoginSuccess")
			.and().csrf().disable(); // disable CSRF
	}
	
	@Override
	protected void configure(AuthenticationManagerBuilder auth) throws Exception {
	   // Adding in memory User for form based login
		auth.inMemoryAuthentication()
		.passwordEncoder(NoOpPasswordEncoder.getInstance()) 
		.withUser("admin")
		.password("admin")
		.roles("USER");	
	}
}