spring-injection parameters in detail-[simplified configuration method]

Overview Literal property value literal property constructor parameter collection element Reference object property literal Value property constructor parameter collection element use P namespace reference literal property values through p namespace reference other beans by P namespace

Overview

Spring provides a simplified configuration for literals, reference beans, and collections, and can be used in a simplified configuration if no special features are used in full format. Literal property value Literal attributes

<?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 http://www.springframework.org/schema/beans/spring-beans.xsd ">
            <bean id= "Plane" class= "Com.xgj.ioc.inject.set.Plane" > <!--<property name= "Brand" > <value>Airbus&amp; a380</value> </property> <property name= "Color" > <value>red</value > </property> <property name= "Speed" > <value>700</value> & Lt;/property>-<!--simplified configuration--<property name= "brand" value= "airbus&amp;
    A380 "/> <property name=" color "value=" red "/> <property name=" Speed "value=" ></property> " </bean> </beans> 

Using a simplified method, you cannot use constructor parameters

<?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 http://www.springframework.org/schema/beans/spring-beans.xsd ">

    < Bean id= "Tank" class= "Com.xgj.ioc.inject.construct.type.Tank" >

        <!-- 
        <constructor-arg type= " Java.lang.String ">
            <value>T72</value>
        </constructor-arg>

        <constructor-arg Type= "Double" >
            <value>20000.00</value>
        </constructor-arg>--

         < !--Simplified Way-
         <constructor-arg type= "java.lang.String"  value= "T72"/>
         <constructor-arg  type= "Double" value= "20000.00"/>

    </bean>
</beans>

Collection Elements

<?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 Http://www.springframework.org/schema/beans/spring-beans.xsd "> <bean id=" Pets "class=" Com.xgj.ioc.inject.construct.jihe.strongType.Pets "> <property name=" Map "> <!--& Lt;map> <entry> <key> provides a value for integer, and when spring sets the value, it
                    Convert to defined integer type <value>111</value> </key> <value>cat</value> </entry> <entry> <key > <value>113</value> </key> <value
      >bird</value> </entry>          <entry> <key> <value>115</value> </key> <value>dog</value> </entry> </m Ap>-<!--simplified-<map> <entry key= "111" value= "C
            At "/> <entry key=" 113 "value=" Bird "/> <entry key=" $ "value=" dog "/> </map> </property> </bean> <bean id= "PetShop" class= "com.xgj.ioc.inject.constr
 Uct.jihe.strongType.PetShop "> <property name=" Pets "ref=" pets "/> </bean> </beans>

Referencing Object Properties Literal attributes

A complex way

<property name= "Plane" >
    <ref bean= "plane"/>
</property>

A simplified approach

<property name= "plane" ref= "plane"/>

constructor Parameters

A complex way

<constructor-arg>
    <ref bean= "plane" >
</constructor-arg>

A simplified approach

<constructor-arg ref= "Plane" >

Collection Elements

A complex way

<map>
    <entry>
        <key>
            <ref bean= "Keybean"/>
        </key>
        <ref bean= "Valuebean"/>
    </entry>
</map>

A simplified approach

<map>
    <entry key-ref= "Keybena" value-ref= "Valuebean"/>
</map>

The simplified form of the ref label corresponds to <ref bean= "xxx" > <ref local= "xxx" > and <ref parent= "xxx" > No corresponding simplified form using the P-namespace

The new P-namespace is introduced after the Spring2.5 version, and the Bean's properties can be configured through the bean element properties.

With the P namespace, XML-based configuration is further simplified.

Need to introduce

xmlns:p= "http://www.springframework.org/schema/p"

referencing literal property values through the P-namespace

<?xml version= "1.0" encoding= "UTF-8"?> <beans
xmlns= "Http://www.springframework.org/schema/beans"
    xmlns:xsi= "Http://www.w3.org/2001/XMLSchema-instance"
    introduces the P-namespace
    xmlns:p= "/http www.springframework.org/schema/p "

    xsi:schemalocation=" Http://www.springframework.org/schema/beans/http Www.springframework.org/schema/beans/spring-beans.xsd ">


    <!--use P namespace--
    <bean id=" Plane " class= "Com.xgj.ioc.inject.set.Plane"
        p:brand= "airbus&amp; A380 "
        p:color=" Red "
        p:speed="
    >
    </bean>

</beans>

referencing other beans through the P-namespace

<?xml version= "1.0" encoding= "UTF-8"?> <beans
xmlns= "Http://www.springframework.org/schema/beans"
    xmlns:p= "http://www.springframework.org/schema/p"
    xmlns:xsi= "http://www.w3.org/2001/ Xmlschema-instance "
    xsi:schemalocation=" Http://www.springframework.org/schema/beans/http Www.springframework.org/schema/beans/spring-beans.xsd ">

    <!-- 
    <bean id=" police "class=" Com.xgj.ioc.inject.construct.ref.Police ">
        <property name=" Gun ">
             by using the gun in the REF application container, Build police and gun dependencies 
            <ref bean= "gun"/>
        </property> </bean>-

     <!-- Use the P namespace to  refer to other bean-->
    <bean id= "police" class= "Com.xgj.ioc.inject.construct.ref.Police"
        p: Gun-ref= "Gun"/>

    <bean id= "gun" class= "Com.xgj.ioc.inject.construct.ref.Gun"/>
</beans>

,<bean> use <property> child elements to configure bean properties before the P namespace is used.
With the P namespace, the attributes of the bean are configured with the element attributes of <bean>.

For literal attributes, the format is

p:< property name >-ref= "XXX"

The property of the referenced object, in the form of:

p:< property name >-ref= "XXX"

Because property names in the P namespace are mutable, there is no schema definition file for the P namespace and no schema definition file for the P namespace in xsi:schemalocation.