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Using Spring XML Schema based bean definitions

Spring's bean definitions (and configuration files) may go very verbose after your projects goes two or three iterations old. By verbose I mean, too many bean definitions, and complex injection graph. And many a times, these xml files go fat because of common definition types - props, lists, etc. These beans are generally configured using FactoryBeans.

To reduce this verbatim Spring provides XML schema based configuration, for various types of FactoryBeans. There are some shortcuts presented in that appendix, I frequently use. I recomend those to others too.

Here are some of those.

<!-- creates a java.util.Properties instance with values loaded from the supplied location -->
<bean id="jdbcConfiguration" class="org.springframework.beans.factory.config.PropertiesFactoryBean">
  <property name="location" value="classpath:com/foo/jdbc-production.properties"/>
</bean>
Could be written as
<!-- creates a java.util.Properties instance with values loaded from the supplied location -->
<util:properties id="jdbcConfiguration" location="classpath:com/foo/jdbc-production.properties"/>

<bean id="emails" class="org.springframework.beans.factory.config.ListFactoryBean">
  <property name="sourceList">
      <list>
        <value>pechorin@hero.org</value>
        <value>raskolnikov@slums.org</value>
        <value>stavrogin@gov.org</value>
        <value>porfiry@gov.org</value>
      </list>
  </property>
</bean>
Could be Written as
<!-- creates a java.util.List instance with values loaded from the supplied 'sourceList' -->
<util:list id="emails">
    <value>pechorin@hero.org</value>
    <value>raskolnikov@slums.org</value>
    <value>stavrogin@gov.org</value>
    <value>porfiry@gov.org</value>
</util:list>

<util:map/> is similar.


<bean id="simple" class="org.springframework.jndi.JndiObjectFactoryBean">
    <property name="jndiName" value="jdbc/MyDataSource"/>
</bean>
Could become..
<jee:jndi-lookup id="simple" jndi-name="jdbc/MyDataSource"/>

And I love this one

<bean id="simple" class="org.springframework.jndi.JndiObjectFactoryBean">
    <property name="jndiName" value="jdbc/MyDataSource"/>
    <property name="cache" value="true"/>
    <property name="resourceRef" value="true"/>
    <property name="lookupOnStartup" value="false"/>
    <property name="expectedType" value="com.myapp.DefaultFoo"/>
    <property name="proxyInterface" value="com.myapp.Foo"/>
</bean>
becomes
<jee:jndi-lookup id="simple"
             jndi-name="jdbc/MyDataSource"
             cache="true"
             resource-ref="true"
             lookup-on-startup="false"
             expected-type="com.myapp.DefaultFoo"
             proxy-interface="com.myapp.Foo"/>

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