先导，对IOC容器的理解
先导，对IOC容器的理解
- 通俗的讲就是把你的class类交给spring的IOC容器去管理
- 需要对该类的属性注入一些值，就可以通过spring提供的xml文件或者注解进行注入
- 自己使用时在IOC容器工厂中去获取就可以了，从而实现控制
1、导入maven依赖 5.3.15版本
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<parent>
<artifactId>pro01-maven-ider-parent</artifactId>
<groupId>com.mhy.maven</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<artifactId>pro06-module-spring</artifactId>
<dependencies>
<!-- https://mvnrepository.com/artifact/junit/junit -->
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
<scope>test</scope>
</dependency>
<!-- https://mvnrepository.com/artifact/org.springframework/spring-webmvc -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>5.3.15</version>
</dependency>
</dependencies>
</project>
2、xml配置文件的常用bean注入
- 实体类
public class Student {
private String name;
private Address address;
private String[] books;
private List<String> hobbys;
private Map<String,String> card;
private Set<String> games;
private Properties info;
private String wife;
}
- bean.xml的依赖注入
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans
https://www.springframework.org/schema/beans/spring-beans.xsd">
<bean id="address" class="com.mhy.pojo.Address">
<property name="address" value="重庆交通大学"/>
</bean>
<bean id="student" class="com.mhy.pojo.Student">
<property name="name" value="mhy"/>
<property name="address" ref="address"/>
<property name="books">
<array>
<value>西游记</value>
<value>红楼梦</value>
<value>水浒传</value>
<value>三国演义</value>
</array>
</property>
<property name="hobbys">
<list>
<value>数学</value>
<value>代码</value>
</list>
</property>
<property name="games">
<set>
<value>LOL</value>
<value>CF</value>
<value>DMF</value>
</set>
</property>
<property name="card">
<map>
<entry key="身份证" value="5002372222287878787"/>
<entry key="学生卡" value="631910040417"/>
</map>
</property>
<property name="info">
<props>
<prop key="driver">com.mysql.jdbc.Driver</prop>
<prop key="url">url=jdbc:mysql://localhost:3306/smbms?characterEncoding=utf8</prop>
<prop key="username">root</prop>
<prop key="password">123456</prop>
</props>
</property>
<property name="wife">
<null/>
</property>
</bean>
</beans>
- 测试的代码
@Test
public void testSpring2(){
ApplicationContext context = new ClassPathXmlApplicationContext("beans2.xml");
Student student = context.getBean("student", Student.class);
System.out.println(student);
/*结果--->
Student{name='mhy',
address=Address{address='重庆交通大学'},
books=[西游记, 红楼梦, 水浒传, 三国演义],
hobbys=[数学, 代码],
card={身份证=5002372222287878787, 学生卡=631910040417},
games=[LOL, CF, DMF],
info={
password=123456,
url=url=jdbc:mysql://localhost:3306/smbms?characterEncoding=utf8,
driver=com.mysql.jdbc.Driver,
username=root},
wife='null'}
*/
}
- p和c标签的使用
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:p="http://www.springframework.org/schema/p"
xmlns:c="http://www.springframework.org/schema/c"
xsi:schemaLocation="http://www.springframework.org/schema/beans
https://www.springframework.org/schema/beans/spring-beans.xsd">
<bean id="hello" class="com.mhy.pojo.Hello">
<property name="str" value="hello spring"/>
</bean>
<bean id="hello4" class="com.mhy.pojo.Hello">
<property name="str" value="hello spring 2"/>
</bean>
<bean id="hello2" class="com.mhy.pojo.Hello" p:str="hello spring p"/>
<bean id="hello3" class="com.mhy.pojo.Hello" c:str="hello spring c"/>
</beans>
注意:
- c标签是set注入
- p标签是有参数构造注入
