Spring IOC again
参数值注入
注入基本值
注入Bean对象
注入Spring表达式值
注入null或空字符串
注入集合
注入集合方式1:
<!-- 指定配置文件路径,注入Spring表达式 -->
<util:properties id="jdbcProperties" location="classpath:db.properties"/>
<bean id="messageBean" class="org.com.ky.MessageBean">
<property name="moduleName" value="资费管理"></property>
<property name="pageSize" value="5"></property>
<!-- 注入基本值 -->
<!-- <property name="userName" value="scott"></property> -->
<!-- 注入Spring表达式 -->
<property name="userName" value="#{jdbcProperties.user}">
</property>
<!-- <property name="passWord" value="tiger"></property>-->
<!-- 注入null或空字符串 -->
<property name="passWord" >
<null/>
</property>
<!-- 注入集合List,Set,Map,Property 方式1 -->
<property name="someList" >
<list>
<value>北京</value>
<value>上海</value>
<value>南京</value>
</list>
</property>
<property name="someSet" >
<set>
<value>AAA</value>
<value>BBB</value>
<value>CCC</value>
</set>
</property>
<property name="someMap" >
<map>
<entry key="1001" value="muji"></entry>
<entry key="1002" value="family"></entry>
<entry key="1003" value="Love"></entry>
</map>
</property>
<property name="somePro" >
<props>
<prop key="userName">root</prop>
<prop key="pwd">123</prop>
</property>
</bean>
注入集合方式2:
<util:list id="firList">
<value>A0</value>
<value>A1</value>
<value>A2</value>
</util:list>
<util:set id="firSet">
<value>AMD</value>
<value>Intel</value>
<value>IOS</value>
</util:set>
<util:map id="firMap">
<entry key="0001" value="OOO"></entry>
<entry key="0002" value="OOP"></entry>
<entry key="0003" value="OOJ"></entry>
</util:map>
<util:properties id="firPro">
<prop key="1001">rooot</prop>
<prop key="username">1234</prop>
</util:properties>
<bean id="ms2" class="org.com.ky.MessageBean">
<property name="moduleName" value="资费管理"></property>
<property name="pageSize" value="5"></property>
<property name="userName" value="scott"></property>
<property name="passWord" value="tiger"></property>
<!-- 引用方式注入集合属性 -->
<property name="someList" ref="firList"></property>
<property name="someSet" ref="firSet"></property>
<property name="someMap" ref="firMap"></property>
<property name="somePro" ref="firPro"></property>
</bean>
码代码过程中遇到的问题:
解决方案:
<?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:context="http://www.springframework.org/schema/context"
xmlns:jdbc="http://www.springframework.org/schema/jdbc"
xmlns:jee="http://www.springframework.org/schem/jee"
xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:jpa="http://www.springframework.org./schema/data/jpa"
xmlns:util="http://www.springframework.org/schema/util"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.2.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.2.xsd
http://www.springframework.org/schema/jdbc
http://www.springframework.org/schema/jdbc/spring-jdbc-3.2.xsd
http://www.springframework.org/schema/jee
http://www.springframework.org/schema/jee/spring-jee-3.2.xsd
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
http://www.springframework.org/schema/data/jpa
http://www.springframework.org/schema/data/jpa/spring-jpa-1.3.xsd
http://www.springframework.org/schema/util
http://www.springframework.org.schema/util/spring-util-3.2.xsd">
</beans>
添加上:
报错2:
解决方法,改成
http://www.springframework.org/schema/util
http://www.springframework.org/schema/util/spring-util-3.2.xsd
基于注解的组件扫描
- What is 组件扫描
指定包的路径,Spring会自动扫描包及其子包所有组件类, 当发现组件类定义前有特定的注解标记时,就将该组件纳入到Spring容器中,相当于在XML配置文件中<bean>的定义 - 指定扫描路径
- 自动扫描的注解标记
| 注解标记| 描述 |
|: -------------: |:-------------|
|@Name | 通用注解|
| @Component | 通用注解 |
| @Repository| 持久化层组件注解,数据层 |
| @Service| 业务层注解 |
| @Controller| 控制层注解 |
| @Resource| 用于字段定义或setter方法定义前 ,默认首先按名称匹配注入,然后按类型匹配注入|
| @Autowired| 按照类型自动装配, 用于字段定义或setter方法定义前,默认按类型匹配 |
| @Inject| 用于字段定义或setter方法定义前,默认按类型匹配 |
| @Value| 注入Spring表达式值 |
@Resource 注解:
@Resource
private UserDao userDao;
public UserDao getUserDao() {
return userDao;
}
//@Resource
public void setUserDao(UserDao userDao) {
this.userDao = userDao;
}
@Autowired注解:多个匹配Bean注入发生错误,解决方法
@Autowired
//@Qualifier("mySqlUserDao")
private UserDao userDao;
public UserDao getUserDao() {
return userDao;
}
public void setUserDao(@Qualifier("mySqlUserDao")UserDao userDao) {
this.userDao = userDao;
}
@Inject注解:多个匹配Bean注入发生错误,可以用@Named指定名称限定
private UserDao userDao;
@Inject
public UserDao getUserDao() {
return userDao;
}
public void setUserDao(@Named("mySqlUserDao")UserDao userDao) {
this.userDao = userDao;
}
@Value注解:
<!-- 指定配置文件路径,注入Spring表达式 -->
<util:properties id="jdbcProperties" location="classpath:db.properties"/>
@Value("#{jdbcProperties.driver}")
private String driver;
@Value("#{jdbcProperties.url}")
private String url;
@Value("#{jdbcProperties.user}")
private String user;