结合使用context：property-override和PropertyPlaceholderConfigurer

Question

I have a problem with the followingspring context configuration file:

...
   <context:property-override location="classpath:query_1.properties" />
        <bean
            class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
            <property name="locations" value="classpath:query_2.properties" />
        </bean>
....

The problem is that the properties in the file "query_2.properties" cannot be found. The exception I get ist he following one:

Exception in thread "main" org.springframework.beans.factory.BeanDefinitionStoreException. Could not resolve placeholder...

Now my question: is it possible that the combination of context:property-override and PropertyPlaceholderConfigurer does make no sense? Can anyone explain me in simple words what is the difference between both? Any help would be appreciated.

Thx. Horace

Answer 1

Property placeholders, normally defined using a <context:property-placeholder location=../> resolves the placeholders in bean definitions:

for eg.

<bean name="myclass" class="MyClass">
    <property name="prop1" value="${prop1val}/>
</bean>

if the location specified with property placeholder has a property with name prop1val:

prop1val=aval

then it will be replaced in the bean myclass .

PrpertyOverrideConfigurer defined using <context:property-override location="classpath:query_1.properties" /> on the other is like a push mechanism, the property is of the form beanname.property and it would push this property into the bean with name beanname .

For eg. for the above case if the location had a property of:

myclass.prop1=aval

then it would inject in prop1 of myclass bean

The exception you are getting simply indicates that it is not able to find query_2.properties file, I doubt if it is any other configuration issue.

On which one will take effect if both are defined, I think the last one will the one to take effect.