【第六篇】深入理解SecurityConfigurer源码

//  O（DefaultSecurityFilterChain）  B（HttpSecurity）
public interface SecurityConfigurer<O, B extends SecurityBuilder<O>> {

	/**
	 * Initialize the {@link SecurityBuilder}. Here only shared state should be created
	 * and modified, but not properties on the {@link SecurityBuilder} used for building
	 * the object. This ensures that the {@link #configure(SecurityBuilder)} method uses
	 * the correct shared objects when building. Configurers should be applied here.
	 * @param builder
	 * @throws Exception
	 */
	void init(B builder) throws Exception;

	/**
	 * Configure the {@link SecurityBuilder} by setting the necessary properties on the
	 * {@link SecurityBuilder}.
	 * @param builder
	 * @throws Exception
	 */
	void configure(B builder) throws Exception;

}

@Order(100)
public abstract class GlobalAuthenticationConfigurerAdapter
		implements SecurityConfigurer<AuthenticationManager, AuthenticationManagerBuilder> {

	@Override
	public void init(AuthenticationManagerBuilder auth) throws Exception {
	}

	@Override
	public void configure(AuthenticationManagerBuilder auth) throws Exception {
	}

}

public abstract class UserDetailsAwareConfigurer<B extends ProviderManagerBuilder<B>, U extends UserDetailsService>
		extends SecurityConfigurerAdapter<AuthenticationManager, B> {

	/**
     * 返回的是UserDetailsService 接口的实现
	 * Gets the {@link UserDetailsService} or null if it is not available
	 * @return the {@link UserDetailsService} or null if it is not available
	 */
	public abstract U getUserDetailsService();

}

public abstract class AbstractDaoAuthenticationConfigurer<B extends ProviderManagerBuilder<B>, C extends AbstractDaoAuthenticationConfigurer<B, C, U>, U extends UserDetailsService>
		extends UserDetailsAwareConfigurer<B, U> {
// 声明了一个 provider
	private DaoAuthenticationProvider provider = new DaoAuthenticationProvider();
// 声明了一个 userDetailsService 的泛型属性

	private final U userDetailsService;

	/**
	 * Creates a new instance
构造器 传递的对象可以是UserDetailsService或者UserDetailsPasswordService
	 * @param userDetailsService
	 */
	AbstractDaoAuthenticationConfigurer(U userDetailsService) {
		this.userDetailsService = userDetailsService;
		this.provider.setUserDetailsService(userDetailsService);
		if (userDetailsService instanceof UserDetailsPasswordService) {
			this.provider.setUserDetailsPasswordService((UserDetailsPasswordService) userDetailsService);
		}
	}

	/**
	 * Adds an {@link ObjectPostProcessor} for this class.
添加了一个ObjectPostProcessor 后置处理器
	 * @param objectPostProcessor
	 * @return the {@link AbstractDaoAuthenticationConfigurer} for further customizations
	 */
	@SuppressWarnings("unchecked")
	public C withObjectPostProcessor(ObjectPostProcessor<?> objectPostProcessor) {
		addObjectPostProcessor(objectPostProcessor);
		return (C) this;
	}

	/**
添加密码编码器 加密
	 * Allows specifying the {@link PasswordEncoder} to use with the
	 * {@link DaoAuthenticationProvider}. The default is to use plain text.
	 * @param passwordEncoder The {@link PasswordEncoder} to use.
	 * @return the {@link AbstractDaoAuthenticationConfigurer} for further customizations
	 */
	@SuppressWarnings("unchecked")
	public C passwordEncoder(PasswordEncoder passwordEncoder) {
		this.provider.setPasswordEncoder(passwordEncoder);
		return (C) this;
	}

	public C userDetailsPasswordManager(UserDetailsPasswordService passwordManager) {
		this.provider.setUserDetailsPasswordService(passwordManager);
		return (C) this;
	}

	@Override
	public void configure(B builder) throws Exception {
// 调用后置处理器 将provider添加到SpringIoC容器中
		this.provider = postProcess(this.provider);
// 将provider添加到builder对象中
		builder.authenticationProvider(this.provider);
	}

	/**
	 * Gets the {@link UserDetailsService} that is used with the
	 * {@link DaoAuthenticationProvider}  重写父类的方法
	 * @return the {@link UserDetailsService} that is used with the
	 * {@link DaoAuthenticationProvider}
	 */
	@Override
	public U getUserDetailsService() {
		return this.userDetailsService;
	}

}

public class UserDetailsServiceConfigurer<B extends ProviderManagerBuilder<B>, C extends UserDetailsServiceConfigurer<B, C, U>, U extends UserDetailsService>
		extends AbstractDaoAuthenticationConfigurer<B, C, U> {

	/**
	 * Creates a new instance
	 * @param userDetailsService the {@link UserDetailsService} that should be used
	 */
	public UserDetailsServiceConfigurer(U userDetailsService) {
		super(userDetailsService);
	}

	@Override
	public void configure(B builder) throws Exception {
		initUserDetailsService();
		super.configure(builder);
	}

	/**
	 * Allows subclasses to initialize the {@link UserDetailsService}. For example, it
	 * might add users, initialize schema, etc.
	 */
	protected void initUserDetailsService() throws Exception {
	}

}

public class InMemoryUserDetailsManagerConfigurer<B extends ProviderManagerBuilder<B>>
		extends UserDetailsManagerConfigurer<B, InMemoryUserDetailsManagerConfigurer<B>> {

	/**
	 * Creates a new instance
	 */
	public InMemoryUserDetailsManagerConfigurer() {
		super(new InMemoryUserDetailsManager(new ArrayList<>()));
	}

}