Spring3.0官网文档学习笔记（七）--3.4.2

标签：官网文档   spring3.0   学习笔记   

<bean id="myDataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">

<!-- results in a setDriverClassName(String) call -->
<property name="driverClassName" value="com.mysql.jdbc.Driver"/>
<property name="url" value="jdbc:mysql://localhost:3306/mydb"/>
<property name="username" value="root"/>
<property name="password" value="masterkaoli"/>
</bean>

    使用p-namespace使得拼写更加简洁（但是拼写错误会在运行时才被发现，而不是在编辑时，除非使用Intellij IDEA或者SpringSource Tool Suite）

<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"
     xsi:schemaLocation="http://www.springframework.org/schema/beans
     http://www.springframework.org/schema/beans/spring-beans-3.0.xsd">

<bean id="myDataSource" class="org.apache.commons.dbcp.BasicDataSource"
      destroy-method="close"
      p:driverClassName="com.mysql.jdbc.Driver"
      p:url="jdbc:mysql://localhost:3306/mydb"
      p:username="root"
      p:password="masterkaoli"/>

</beans>

<bean id="mappings"
    class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">

 <!-- typed as a java.util.Properties -->
 <property name="properties">
    <value>
       jdbc.driver.className=com.mysql.jdbc.Driver
       jdbc.url=jdbc:mysql://localhost:3306/mydb
    </value>
 </property>
</bean>

<bean id="theTargetBean" class="..."/>

<bean id="theClientBean" class="...">
  <property name="targetName">
      <idref bean="theTargetBean" />
  </property>
</bean>

<bean id="theTargetBean" class="..." />

<bean id="client" class="...">
  <property name="targetName" value="theTargetBean" />
</bean>

     此外，如果被引用的bean再同一个xml单元，而且bean的名字就是bean的id，那么可以使用local属性。这样一来允许xml解析器更早的去验证bean。

<property name="targetName">
 <!-- a bean with id ‘theTargetBean‘ must exist; otherwise an exception will be thrown -->
 <idref local="theTargetBean"/>
</property>

<!-- in the parent context -->
<bean id="accountService" class="com.foo.SimpleAccountService">
  <!-- insert dependencies as required as here -->
</bean>

<!-- in the child (descendant) context -->
<bean id="accountService"  <-- bean name is the same as the parent bean -->
    class="org.springframework.aop.framework.ProxyFactoryBean">
    <property name="target">
        <ref parent="accountService"/>  <!-- notice how we refer to the parent bean -->
    </property>
  <!-- insert other configuration and dependencies as required here -->
</bean>

<bean id="outer" class="...">
<!-- instead of using a reference to a target bean, simply define the target bean inline -->
<property name="target">
  <bean class="com.example.Person"> <!-- this is the inner bean -->
    <property name="name" value="Fiona Apple"/>
    <property name="age" value="25"/>
  </bean>
</property>
</bean>

3.4.2.4 集合

<bean id="moreComplexObject" class="example.ComplexObject">
<!-- results in a setAdminEmails(java.util.Properties) call -->
<property name="adminEmails">
  <props>
      <prop key="administrator">administrator@example.org</prop>
      <prop key="support">support@example.org</prop>
      <prop key="development">development@example.org</prop>
  </props>
</property>
<!-- results in a setSomeList(java.util.List) call -->
<property name="someList">
  <list>
      <value>a list element followed by a reference</value>
      <ref bean="myDataSource" />
  </list>
</property>
<!-- results in a setSomeMap(java.util.Map) call -->
<property name="someMap">
  <map>
      <entry key="an entry" value="just some string"/>
      <entry key ="a ref" value-ref="myDataSource"/>
  </map>
</property>
<!-- results in a setSomeSet(java.util.Set) call -->
<property name="someSet">
  <set>
      <value>just some string</value>
      <ref bean="myDataSource" />
  </set>
</property>
</bean>

bean | ref | idref | list | set | map | props | value | null

<beans>
<bean id="parent" abstract="true" class="example.ComplexObject">
  <property name="adminEmails">
      <props>
          <prop key="administrator">administrator@example.com</prop>
          <prop key="support">support@example.com</prop>
      </props>
  </property>
</bean>
<bean id="child" parent="parent">
  <property name="adminEmails">
      <!-- the merge is specified on the *child* collection definition -->
      <props merge="true">
          <prop key="sales">sales@example.com</prop>
          <prop key="support">support@example.co.uk</prop>
      </props>
  </property>
</bean>
<beans>

administrator=administrator@example.com
sales=sales@example.com
support=support@example.co.uk

    集合合并的约束：
    你不能使用不同类型的集合进行合并；
    merge属性只能放在子类型的集合端；
    集合合并只在spring2.0及以后的版本提供。

    强类型集合（spring在注入前，先判断accounts的属性，然后将要注入的值转成合适的类型注入）：

public class Foo {

  private Map<String, Float> accounts;

  public void setAccounts(Map<String, Float> accounts) {
      this.accounts = accounts;
  }
}

<beans>
  <bean id="foo" class="x.y.Foo">
      <property name="accounts">
          <map>
              <entry key="one" value="9.99"/>
              <entry key="two" value="2.75"/>
              <entry key="six" value="3.99"/>
          </map>
      </property>
  </bean>
</beans>

<bean class="ExampleBean">
<property name="email" value=""/>
</bean>

   上述跟exampleBean.setEmail("")的效果是一样的；

<bean class="ExampleBean">
<property name="email"><null/></property>
</bean>

3.4.2.5 xml使用p-namespace作为快捷方式
    Spring2.0及之后的版本支持。
    p-namespace并不是被定义在xsd文件，而是只存在于Spring的core。  

<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"
  xsi:schemaLocation="http://www.springframework.org/schema/beans
      http://www.springframework.org/schema/beans/spring-beans-3.0.xsd">

  <bean name="classic" class="com.example.ExampleBean">
      <property name="email" value="foo@bar.com"/>
  </bean>

  <bean name="p-namespace" class="com.example.ExampleBean"
        p:email="foo@bar.com"/>
</beans>

<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"
  xsi:schemaLocation="http://www.springframework.org/schema/beans
      http://www.springframework.org/schema/beans/spring-beans-3.0.xsd">

  <bean name="john-classic" class="com.example.Person">
      <property name="name" value="John Doe"/>
      <property name="spouse" ref="jane"/>
  </bean>

  <bean name="john-modern"
      class="com.example.Person"
      p:name="John Doe"
      p:spouse-ref="jane"/>

  <bean name="jane" class="com.example.Person">
      <property name="name" value="Jane Doe"/>
  </bean>
</beans>

<bean id="foo" class="foo.Bar">
<property name="fred.bob.sammy" value="123" />
</bean>

Spring3.0官网文档学习笔记（七）--3.4.2,布布扣,bubuko.com

Spring3.0官网文档学习笔记（七）--3.4.2

标签：官网文档   spring3.0   学习笔记   

原文地址：http://blog.csdn.net/abauch_d/article/details/32940579