spring使用多個PropertyPlaceholderConfigurer的配置

Spring中PropertyPlaceholderConfigurer這個類，它是用來解析Java Properties屬性檔案值，並提供在spring配置期間替換使用屬性值。接下來讓我們逐漸的深入其配置。

基本的使用方法是：(1)

<bean id="propertyConfigurerForAnalysis" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
    <property name="location">
        <value>classpath:/spring/include/dbQuery.properties</value>
    </property>
</bean>

其中classpath是引用src目錄下的檔案寫法。

當存在多個Properties檔案時，配置就需使用locations了：(2)

<bean id="propertyConfigurer" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
    <property name="locations">
       <list>
          <value>classpath:/spring/include/jdbc-parms.properties</value>
          <value>classpath:/spring/include/base-config.properties</value>
        </list>
    </property>
</bean>

接下來我們要使用多個PropertyPlaceholderConfigurer來分散配置，達到整合多工程下的多個分散的Properties檔案，其配置如下：(3)

<bean id="propertyConfigurerForProject1" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
    <property name="order" value="1" />
    <property name="ignoreUnresolvablePlaceholders" value="true" />
    <property name="location">
       <value>classpath:/spring/include/dbQuery.properties</value>
    </property>
</bean>

<bean id="propertyConfigurerForProject2" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
    <property name="order" value="2" />
    <property name="ignoreUnresolvablePlaceholders" value="true" />
    <property name="locations">
      <list>
        <value>classpath:/spring/include/jdbc-parms.properties</value>
        <value>classpath:/spring/include/base-config.properties</value>
      </list>
    </property>
</bean>

其中order屬性代表其載入順序，而ignoreUnresolvablePlaceholders為是否忽略不可解析的Placeholder，如配置了多個PropertyPlaceholderConfigurer，則需設定為true

轉載至：http://wjl198408.blog.163.com/blog/static/2540214720105724845630/