How to use property-placeholder for file on filesystem

Question

We used to have a way to load properties from a file on the classpath:

<context:property-placeholder location="classpath:myConfigFile.properties" />

and it worked great. But now we want to load properties from a specific file on the system that is NOT in the classpath. We wanted to be able to dynamically load the file, so we are using a Java environment variable to populate it. I'll give a simple example below:

In Java:

  System.setProperty("my.prop.file", "/path/to/myConfigFile.properties");

In Spring XML:

<context:property-placeholder location="${my.prop.file}" />

I've also tried it this way, thanks to an idea from Luciano:

<context:property-placeholder properties-ref="prop" />

<util:properties id="prop" location="reso"/>

<bean id="reso" class="org.springframework.core.io.FileSystemResource">
    <constructor-arg index="0" value="${my.prop.file}" />
</bean>

Everything I've tried has failed. No matter what I set my.prop.file to. Greatest hits include:

<context:property-placeholder location="/path/to/myConfigFile.properties" />
(ClassNotFoundException: .path.to.myConfigFile.properties)

<context:property-placeholder location="file:/path/to/myConfigFile.properties" />
(ClassNotFoundException: file:.path.to.myConfigFile.properties)

<context:property-placeholder location="file:///path/to/myConfigFile.properties" />
(ClassNotFoundException: file:...path.to.myConfigFile.properties)

How do you use property-placeholders with a location that is on the file system and NOT on the classpath? We are using Spring 3.0.5.

It turns out there was a problem with the script running the Java program that loads the spring file. Thank you for helping. I am going to request that this question be deleted, as the original code works after all. Thank you for your help.

Answer 1

This did work for me:

<context:property-placeholder location="file:/path/to/myConfigFile.properties" />

But this (interestingly) did not:

<context:property-placeholder location="#{ systemProperties['foo'] }" />

I got

java.io.FileNotFoundException: Could not open ServletContext resource [/#{ systemProperties['foo'] }]

You're not going to be able to use a property placeholder ${..} with the definition of a PropertyPlaceholderConfigurer. It's the chicken before the egg.

You can always subclass PropertyPlaceholderConfigurer and have it do whatever you want (for example, call setLocations() in a @PostConstruct method. Then, instead of using <context:property-placeholder>, use:

<bean class="com.foo.MyPropertyPlaceholderConfigurer"/>

Answer 2

What about this way?

<context:property-placeholder properties-ref="prop" />

<util:properties id="prop" location="reso"/>

<bean id="reso" class="org.springframework.core.io.FileSystemResource">
    <constructor-arg index="0" value="/yourpathandfile" />
</bean>