Spring-DI-IOC
1. Spring导包
spring-context
spring-core
spring-beans
commons-logging
spring-aop
spring-expression
spring-test
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>5.1.5.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>5.1.5.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-beans</artifactId>
<version>5.1.5.RELEASE</version>
</dependency>
<dependency>
<groupId>commons-logging</groupId>
<artifactId>commons-logging</artifactId>
<version>1.2</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-aop</artifactId>
<version>5.1.5.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-expression</artifactId>
<version>5.1.5.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-test</artifactId>
<version>5.1.5.RELEASE</version>
<scope>test</scope>
</dependency>
2. Spring模块
3. bean配置
3.1 基本配置
- id和name:id和name功能相同,name可以使用特殊符号,Spring3.2后不区分id,name
- class:配置bean的完全限定名
- scope:singleton(单例模式)、prototype(多例模式)
- lazy-init:true(懒加载模式)、false(迫切加载)
3.2 生命周期
- init-method:配置初始化方法。
- destroy-method:配置销毁bean对象的方法。
3.3 属性注入
3.3.1 通过set方法注入
public class UserDaoImpl implements UserDao {
private DataSource dataSource;
public DataSource getDataSource() {
return dataSource;
}
public void setDataSource(DataSource dataSource) {
this.dataSource = dataSource;
}
}
<bean id="userDaoImpl" class="com.yogie.dao.impl.UserDaoImpl">
<property name="dataSource" ref="dataSource"/>
</bean>
3.3.2 通过构造方法注入
public class Admin {
public String uuid;
public User user;
public Admin(String uuid, User user) {
this.uuid = uuid;
this.user = user;
}
}
<bean id="user" class="com.yogie.domain.User" >
<property name="username" value="tom"/>
<property name="age" value="18"/>
</bean>
<bean id="admin" class="com.yogie.domain.Admin">
<constructor-arg name="uuid" value="4647ad93-f1d1-4820-b073-de6454fb476c"/>
<constructor-arg name="user" ref="user"/>
</bean>
4. BeanFactory
ClassPathResource resource = new ClassPathResource("applicationContext.xml");
BeanFactory factory = new XmlBeanFactory(resource);
User user1 = (User)factory.getBean("user");
System.out.println(user1);
5. ApplicationContext
ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");
User user2 = context.getBean(User.class);
System.out.println(user2);
6. BeanFactory与ApplicationContext的区别
- BeanFactory与ApplicationContext都是接口。
- ApplicationContext继承自BeanFactory。
- ApplicationContext是在启动容器创建上下文环境的时候就创建Bean对象(预先加载,迫切加载)。
- BeanFactory是在使用的时候才进行对象的创建(懒加载)。
7. Spring测试
- 普通的junit测试不能对spring的配置文件进行加载。
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("classpath:applicationContext.xml")
public class UserControllerTest {
@Autowired
ApplicationContext context;
@Test
public void service() {
UserController controller = context.getBean(UserController.class);
controller.service();
}
}
8. Spring配置数据库连接池
jdbc.driverClassName=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/jdbcwork?useSSL=false
jdbc.username=root
jdbc.password=123456
<context:property-placeholder location="classpath:jdbc.properties"/>
<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource">
<property name="driverClassName" value="${jdbc.driverClassName}"/>
<property name="url" value="${jdbc.url}"/>
<property name="username" value="${jdbc.username}"/>
<property name="password" value="${jdbc.password}"/>
</bean>