Wiring a bean from a database

[blfinche]

I am wiring a bean with the port values from our developer machines. I would like to retrieve the value from a database. I think a custom property editor would be the right way to accomplish this. Is there another way of accomplishing this?

Thanks,
Bobby

[Alarmnummer]

You could use a PropertyPlaceholderConfigurer to externalize the properties. And there is another (spring) project that has created a few implementation (not only property files, but database access aswel), but I can`t find the link.

[Costin Leau]

Not sure if it helps, but Spring Modules provides integration with Commons Configuration.

[Dave Syer]

The Spring modules factory bean looks interesting, but I couldn't find any documentation (except the extremely minimal javadocs). Could you add a section / example to the main HTML docs?

[Costin Leau]

Sure - can you please raise an issue on JIRA to keep track of it? Thanks.

[deepannair]

I tried uisng the above setup for a properties configurer. i get the following e rror
org.springframework.beans.NotWritablePropertyExcep tion: Invalid property 'propertiesArray' of bean class [org.springframework.beans.factory.config.PropertyP laceholderConfigurer]: Bean property 'proper
tiesArray' is not writable or has an invalid setter method: Does the parameter type of the setter match the return type of the getter?

Any idea why this is happening?
Regards,
Deepa

[karldmoore]

I would presume as the method does exist, the arguments being passed in don't match the expected ones. It expects Properties[].

http://static.springframework.org/sp...perties[])

[hay7777]

Does anyone know where this is? I need it too!

cheers,

David

[wpoitras]

Here is a configuration file which loads properties from a database using Apache Commons Configuration (whose connection properties are loaded from db.properties). Since I'm using two PropertyPlaceholderConfigurer, I needed to use a different placeholderPrefix for the file based one. That way the properties in the rest of the context uses normal syntax:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http&#58;//www.springframework.org/dtd/spring-beans.dtd">
<beans>
	<bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
		<property name="location" value="db.properties"/>
		<property name="placeholderPrefix" value="$&#123;init&#58;"/>
	</bean>
	
	<bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
		<property name="properties">
			<bean factory-class="org.apache.commons.configuration.ConfigurationConversion"
	      		  factory-method="getProperties">
		  		<constructor-arg>
					<bean class="org.apache.commons.configuration.DatabaseConfiguration">
				  		<constructor-arg>
			   				<bean class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
						      <property name="driverClassName" value="$&#123;init&#58;jdbc.driver&#125;"/>
						      <property name="url" value="$&#123;init&#58;jdbc.url&#125;"/>
						      <property name="username" value="$&#123;init&#58;jdbc.username&#125;"/>
						      <property name="password" value="$&#123;init&#58;jdbc.password&#125;"/>
						    </bean> 	
						</constructor-arg>
  					    <constructor-arg value="$&#123;init&#58;table&#125;"/>
 					    <constructor-arg value="$&#123;init&#58;keyColumn&#125;"/>
					    <constructor-arg value="$&#123;init&#58;valueColumn&#125;"/>
				    </bean>
				 </constructor-arg>
			</bean>
		</property>
	</bean>
</beans>

[wpoitras]

Actually because of the recursive nature of my solution, you have to break it up into two contexts, with the bootstrap.xml being the parent to context.xml

bootstrap.xml:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http&#58;//www.springframework.org/dtd/spring-beans.dtd">
<beans>
	<bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
		<property name="location" value="db.properties"/>
	</bean>

	<bean id="myProps" class="org.apache.commons.configuration.ConfigurationConverter" factory-method="getProperties">
  		<constructor-arg>
			<bean class="org.apache.commons.configuration.DatabaseConfiguration">
		  		<constructor-arg>
					<bean id="ds1" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
				      <property name="driverClassName" value="$&#123;jdbc.driver&#125;"/>
				      <property name="url" value="$&#123;jdbc.url&#125;"/>
				      <property name="username" value="$&#123;jdbc.username&#125;"/>
				      <property name="password" value="$&#123;jdbc.password&#125;"/>
				    </bean> 	
		  		</constructor-arg>
			    <constructor-arg value="$&#123;config.table&#125;"/>
			    <constructor-arg value="$&#123;config.keyColumn&#125;"/>
			    <constructor-arg value="$&#123;config.valueColumn&#125;"/>
		    </bean>
		 </constructor-arg>
	</bean>
		
</beans>

context.xml:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http&#58;//www.springframework.org/dtd/spring-beans.dtd">
<beans>
	<bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
		<property name="properties" ref="myProps"/>
	</bean>

	<!-- Beans which use the db based properties goes here -->
</beans>