Spring config custom namespace - spring

Question

I have a standalone spring application with an embedded Apache FTP server. The config looks like this -
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:afs="http://mina.apache.org/ftpserver/spring/v1"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd
http://mina.apache.org/ftpserver/spring/v1 http://mina.apache.org/ftpserver/ftpserver-1.0.xsd">
<context:property-placeholder location="classpath:config.properties" system-properties-mode="OVERRIDE"/>
<afs:server id="server" anon-enabled="false">
<afs:listeners>
<afs:nio-listener name="default" port="2222"
idle-timeout="60" />
</afs:listeners>
<!-- other AFS config -->
</afs:server>
</beans>
I would like to load the port property of nio-listener from a properties files, but
<afs:nio-listener name="default" port="${ftp.port}"
idle-timeout="60" />
doesn't work, since port is defined in the xsd as xs:int. I'd like to know if there is any workaround (using SpEL?) that will allow me to use the AFS namespace and load the port property from a file or from system properties.

Answer 1

You could try with PropertyOverrideConfigurer.
The problem is that you need to know the bean name that the <afs:server> tag define (may be 'server') and the property type that <afs:listeners> define (may be a managed list of bean definitions).
Look at STS bean explorer to find correct answers and try whith something like
<context:property-override location="classpath:config.properties" />
server.listeners[0].port=2222
Other option is disable schema validation setting validating to false before refresh in the xml application context.
ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext(
new String[] {"applicationContext.xml"}, false);
context.setValidating(false);
context.refresh();

Answer 2

After exploring a few options, I've decided that the easiest way is to step outside the afs namespace for the just the listener configuration. Final config looks like this -
<bean id="listenerFactory" class="org.apache.ftpserver.listener.ListenerFactory">
<property name="port" value="${ftp.port}" />
<property name="dataConnectionConfiguration">
<bean factory-bean="dataConnectionConfigurationFactory"
factory-method="createDataConnectionConfiguration" />
</property>
</bean>
<bean id="dataConnectionConfigurationFactory" class="org.apache.ftpserver.DataConnectionConfigurationFactory" />
<bean id="nioListener" factory-bean="listenerFactory" factory-method="createListener" />
<afs:server id="server" anon-enabled="false">
<afs:listeners>
<afs:listener name="default">
<ref bean="nioListener"/>
</afs:listener>
</afs:listeners>
<!-- other AFS config -->
</<afs:server>