spring注解

随着越来越多地使用Springboot敏捷开发，更多地使用注解配置Spring,而不是Spring的applicationContext.xml文件。

• Configuration注解： Spring解析为配置类，相当于spring配置文件

• Bean注解：容器注册Bean组件，默认id为方法名

  @Configuration public class AppConfig { @Bean public MyService myService() { return new MyServiceImpl(); } }

等同于beans.xml文件

1<beans>
2    <bean id="myService" class="com.acme.services.MyServiceImpl"/>
3</beans>

1）applicationContext.xml文件-包扫描

1@ComponentScans(value = {@ComponentScan(value = "com.self",excludeFilters = {
2                @Filter(type = FilterType.ANNOTATION,classes = {Controller.class})
3        })
4})
5@Configuration
6public class RootConfig {
7    
8      //测试Bean
9      @Bean
10      public Person person() {
11          return new Person("张励",22,"工程师");
12      }
13}

2）导入properties文件

1@PropertySource(value = {"classpath:person.properties"})
2@Configuration
3public class MainConfigOfProperty {
4
5	@Bean
6	public Person person() {
7		return new Person();
8	}
9}

赋值

1public class Person {
2
3   @Value("${person.name}")//配置文件属性
4	private String name;
5
6}

3）数据源

1@EnableTransactionManagement//开启基于注解的事务管理功能
2@ComponentScan("com.self.ds")
3@Configuration
4public class TxConfig {
5	
6	//数据源
7	@Bean
8	public DataSource dataSource() throws Exception{
9		ComboPooledDataSource dataSource = new ComboPooledDataSource();
10		dataSource.setUser("root");
11		dataSource.setPassword("000111");
12		dataSource.setDriverClass("com.mysql.jdbc.Driver");
13		dataSource.setJdbcUrl("jdbc:mysql://localhost:3306/self");
14		return dataSource;
15	}
16	
17	 
18	@Bean
19	public JdbcTemplate jdbcTemplate() throws Exception{ 
20		JdbcTemplate jdbcTemplate = new JdbcTemplate(dataSource());
21		return jdbcTemplate;
22	}
23	
24	//事务管理器
25	@Bean
26	public PlatformTransactionManager transactionManager() throws Exception{
27		return new DataSourceTransactionManager(dataSource());
28	}
29	
30
31}

单元测试

1public class IOCTest {
2	
3	AnnotationConfigApplicationContext applicationContext = new AnnotationConfigApplicationContext(MainConfig.class);  
4	
5	@Test
6	public void test02() {
7		Object bean1 = applicationContext.getBean("person");
8		Object bean2 = applicationContext.getBean("person");
9		System.out.println( bean1 == bean2);
10	}
11	
12	@Test
13	public void test01() {
14		Object bean = applicationContext.getBean("person01");
15		System.out.println("结果: " + bean);
16	}
17	
18	
19	@Test
20	public void test() { 
21		String[] beanDefinitionNames = applicationContext.getBeanDefinitionNames();
22		for(String beanDef:beanDefinitionNames) {
23			System.out.println("输出: " + beanDef);
24		}
25		
26	}
27
28}

执行结果