Spring基础笔记 （二）

@Bean(initMethod="init",destroyMethod = "destory")

@Test
    public void text6(){
        AnnotationConfigApplicationContext applicationContext = new AnnotationConfigApplicationContext(LifeConfig.class);
        Object car = applicationContext.getBean("car");
        System.out.println(car);
        applicationContext.close();
    }

public interface InitializingBean {
    // Bean初始化后调用
  void afterPropertiesSet() throws Exception;
}
public interface DisposableBean {
  // Bean销毁后调用
  void destroy() throws Exception;
}

@Documented
@Retention (RUNTIME)
@Target(METHOD)
public @interface PostConstruct {
}
@Documented
@Retention (RUNTIME)
@Target(METHOD)
public @interface PreDestroy {
}

public interface BeanPostProcessor {
   // 该方法,会在我们说的前三种初始化方法调用之前, 提前调用!!!
   // 返回值,可以是我们新创建好的这个bean,也可以包装一下bean 再返回     
    /* Apply this BeanPostProcessor to the given new bean instance <i>before</i> any bean
   * initialization callbacks (like InitializingBean's {@code afterPropertiesSet}
   * or a custom init-method). The bean will already be populated with property values.
   * The returned bean instance may be a wrapper around the original.
     */
  Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException;
  // 在上面我们所说的三种初始化方法调用之后,立刻调用!!!
  Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException;
}

@Component
public class MyBeanPostProcessor implements BeanPostProcessor {
@Override
public Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException {
    System.out.println("postProcessBeforeInitialization执行了!!!"+"    beanname=="+beanName+"  bean=="+bean);
    return bean;
}
@Override
public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
    System.out.println("postProcessAfterInitialization执行了!!!"+"    beanname=="+beanName+"  bean=="+bean);
    return bean;
}
}

populateBean(beanName,mdb,instanceWrapper);给bean的属性赋值
initlizeBean // 初始化
{
    applyBeanPostProcessorBeforeInitialization()  // 前置处理
    invokeInitMethods(beanName,wrappedBean,mdb); // 执行初始化方法
    applyBeanPostProcessorAfterInitialization() ; // 后置处理
}

<bean id="person" class="com.changwu.bean" scope="prototype">
    <property name="age" value="18"/>
    <property name="name" value="zhangsan"/>
</bean>

1. 基本数值  
@Value("changwu")
private String name;
2. #{}  SPEL表达式
@Value(value ="#{2*2}")
private int  age;
3. ${}  取出配置文件中的值
@Value(value ="${student.age}")
private int  age;

@Target(ElementType.TYPE)
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Repeatable(PropertySources.class)  // 可以写多个
public @interface PropertySource {
String name() default "";
//支持同时加载多个配置文件
String[] value();
// 忽略文件找不到
boolean ignoreResourceNotFound() default false;
//设置编码
String encoding() default "";
/**
 * Specify a custom {@link PropertySourceFactory}, if any.
 * <p>By default, a default factory for standard resource files will be used.
 * @since 4.3
 * @see org.springframework.core.io.support.DefaultPropertySourceFactory
 * @see org.springframework.core.io.support.ResourcePropertySource
 */
Class<? extends PropertySourceFactory> factory() default PropertySourceFactory.class;
}

@Qualifier("bookDao2")
@Autowired
private BookDao bookDao;

// 构造器, 方法,参数,属性,全能!!!
@Target({ElementType.CONSTRUCTOR, ElementType.METHOD, ElementType.PARAMETER, ElementType.FIELD, ElementType.ANNOTATION_TYPE})
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface Autowired {
  /**
   * Declares whether the annotated dependency is required.
   * <p>Defaults to {@code true}.
   */
  boolean required() default true;
}

<dependency>
    <groupId>javax.inject</groupId>
    <artifactId>javax.inject</artifactId>
    <version>1</version>
</dependency>

@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.TYPE, ElementType.METHOD})
@Documented
@Conditional(ProfileCondition.class)
public @interface Profile {
  /**
   * The set of profiles for which the annotated component should be registered.
   */
  String[] value();
}

@Configuration
@PropertySource("classpath:/dbProperlies.properties")
public class MainConfiguration {
    @Value("${db.user}")
    private String user;
    @Value("${db.driverClass}")
    private String driverClass;
    @Profile("text")
    @Bean("TextDBSource")
    public DataSource dataSourceText(@Value("${db.password}") String pwd) {
        ComboPooledDataSource dataSource = new ComboPooledDataSource();
        dataSource.setUser(user);
        dataSource.setPassword(pwd);
        dataSource.setJdbcUrl("jdbc:mysql://localhost:3306/text");
        try {
            dataSource.setDriverClass(driverClass);
        } catch (PropertyVetoException e) {
            e.printStackTrace();
        }
        return dataSource;
    }
    @Profile("dev")
    @Bean("DevDBSource")
    public DataSource dataSourceDev(@Value("${db.password}") String pwd) {
        ComboPooledDataSource dataSource = new ComboPooledDataSource();
        dataSource.setUser(user);
        dataSource.setPassword(pwd);
        dataSource.setJdbcUrl("jdbc:mysql://localhost:3306/person");
        try {
            dataSource.setDriverClass(driverClass);
        } catch (PropertyVetoException e) {
            e.printStackTrace();
        }
        return dataSource;
    }
    @Profile("pro")
    @Bean("ProductDBSource")
    public DataSource dataSourceProduct(@Value("${db.password}") String pwd) {
        ComboPooledDataSource dataSource = new ComboPooledDataSource();
        dataSource.setUser(user);
        dataSource.setPassword(pwd);
        dataSource.setJdbcUrl("jdbc:mysql://localhost:3306/ssh1");
        try {
            dataSource.setDriverClass(driverClass);
        } catch (PropertyVetoException e) {
            e.printStackTrace();
        }
        return dataSource;
    }
}

@Test
    public void text13(){
        // 创建上下文
        AnnotationConfigApplicationContext applicationContext = new AnnotationConfigApplicationContext();
        // 设置需要激活的环境
        applicationContext.getEnvironment().setActiveProfiles("dev");    // 开发环境下注册组件
        // 加载主配置类
        applicationContext.register(MainConfiguration.class);
        // 启动刷新容器
        applicationContext.refresh();
        String[] names = applicationContext.getBeanDefinitionNames();
        for (String name : names) {
            System.out.println(name);
        }
        applicationContext.close();
    }