Spring属性注入的5种方式

 

1.构造方法注入     

　　在xml配置文件中

2.Set注入 

　　　在Java代码中

　　在实体类中必须有set方法

3.复杂类型注入

  　　数组型数据

数组类型
 <bean id="emp" class="com.atguigu.spring6.iocxml.ditest.Emp">
        <!--普通属性-->
        <property name="ename" value="lucy"></property>
        <property name="age" value="20"></property>
        <!--对象类型属性-->
        <property name="dept" ref="dept"></property>
        <!--数组类型属性-->
        <property name="loves">
            <array>
                <value>吃饭</value>
                <value>睡觉</value>
                <value>敲代码</value>
            </array>
        </property>





list 类型

<bean id="dept" class="com.atguigu.spring6.iocxml.ditest.Dept">
  <property name="dname" value="技术部"></property>
  <property name="empList">
        <list>
            <ref bean="empone"></ref>
            <ref bean="emptwo"></ref>
        </list>
  </property>
</bean>




map类型

<bean id="teacherone" class="com.atguigu.spring6.iocxml.dimap.Teacher">
    <!--注入普通类型属性-->
    <property name="teacherId" value="100"></property>
    <property name="teacherName" value="西门讲师"></property>
</bean>
<bean id="teachertwo" class="com.atguigu.spring6.iocxml.dimap.Teacher">
    <!--注入普通类型属性-->
    <property name="teacherId" value="200"></property>
    <property name="teacherName" value="上官讲师"></property>
</bean>

<bean id="student" class="com.atguigu.spring6.iocxml.dimap.Student">
    <!--注入普通类型属性-->
    <property name="sid" value="2000"></property>
    <property name="sname" value="张三"></property>
    <!--在学生bean注入map集合类型属性-->
    <property name="teacherMap">
        <map>
            <entry>
                <key>
                    <value>10010</value>
                </key>
                <ref bean="teacherone"></ref>
            </entry>
            <entry>
                <key>
                    <value>10086</value>
                </key>
                <ref bean="teachertwo"></ref>
            </entry>
        </map>
    </property>
</bean>




p命名空间

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:util="http://www.springframework.org/schema/util"
       xmlns:p="http://www.springframework.org/schema/p"
       xsi:schemaLocation="http://www.springframework.org/schema/util
       http://www.springframework.org/schema/util/spring-util.xsd
       http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans.xsd">

　　<bean id="studentp" class="com.atguigu.spring6.iocxml.dimap.Student"
　　p:sid="100" p:sname="mary" p:lessonList-ref="lessonList" p:teacherMap-ref="teacherMap">
　　</bean>

部属性文件

<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"
       xsi:schemaLocation="http://www.springframework.org/schema/context
       http://www.springframework.org/schema/context/spring-context.xsd
       http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans.xsd">

    <!--引入外部属性文件-->
    <context:property-placeholder location="classpath:jdbc.properties"></context:property-placeholder>