PropertySourcesPlaceholderConfigurer with MethodInvokingFactoryBean - unresolved value - properties

Question

I am using PropertySourcesPlaceholderConfigurer to access a file that contains 2 values :
key1=value1
key2=value2.
<bean id="mainProperties"
class="org.springframework.context.support.PropertySourcesPlaceholderConfigurer" id="">
<property name="locations">
<list>
<value>file:datafile.properties</value>
</list>
</property>
</bean>
values in datafile.properties are then set into system properties using MethodInvokingFactoryBean.
<bean class="org.springframework.beans.factory.config.MethodInvokingFactoryBean">
<property name="targetObject">
<!-- System.getProperties() -->
<bean class="org.springframework.beans.factory.config.MethodInvokingFactoryBean">
<property name="targetClass" value="java.lang.System" />
<property name="targetMethod" value="getProperties" />
</bean>
</property>
<property name="targetMethod"
value="putAll" />
<property name="arguments">
<!-- The new Properties -->
<util:properties>
<prop key="my.key1">${key1}</prop>
<prop key="my.key2">${key2}</prop>
</util:properties>
</property>
</bean>
ISSUE - ${key1} & ${key2} are not resolved. I was expecting that these values will be resolved since i am loading datafile.properties using PropertySourcesPlaceholderConfigurer. Can someone please help ?

Answer 1

I am beginner in Spring. My solution is:
File datafile.properties:
key1=Hellow
key2=world.
Configuration in root-content.xml
<bean id="propertySources"
class="org.springframework.context.support.PropertySourcesPlaceholderConfigurer">
<property name="locations">
<array>
<value>/WEB-INF/jdbc.properties</value>
<value>/WEB-INF/datafile.properties</value>
</array>
</property>
</bean>
<bean id="sysProps"
class="org.springframework.beans.factory.config.MethodInvokingFactoryBean">
<property name="targetClass" value="java.lang.System"/>
<property name="targetMethod" value="getProperties"/>
</bean>
<bean id="myNewProps"
class="org.springframework.beans.factory.config.MethodInvokingFactoryBean">
<property name="targetObject" ref="sysProps"/>
<property name="targetMethod" value="putAll"/>
<property name="arguments">
<map>
<entry key="my.key1" value="${key1}"/>
<entry key="my.key2" value="${key2}"/>
</map>
</property
</bean>
In my central controller MainController.java:
#RequestMapping(value = "/", method = RequestMethod.GET)
public String home() {
//...
Properties prop = System.getProperties();
String myKey1 = prop.getProperty("my.key1");
String myKey2 = prop.getProperty("my.key2");
System.out.println("\nProperties:\n my.key1 = " + myKey1 +
"\n my.key2 = " + myKey2);
//...
}
Console output:
Properties:
my.key1 = Hellow
my.key2 = world.
Note:
When using two placeholderConfigurers, may cause exception: Could not resolve placeholder 'key1' in string value "${key1}". Each of used placeholderConfigurer must have a different placeholder.
For example:
<bean id="propertyConfigurer"
class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
<property name="location" value="/WEB-INF/jdbc.properties"/>
</bean>
<!-- default placeholder ${ } -->
<bean id="propertySources"
class="org.springframework.context.support.PropertySourcesPlaceholderConfigurer">
<property name="locations">
<array>
<value>file:datafile.properties</value>
</array>
</property>
<property name="placeholderPrefix" value="#["></property>
<property name="placeholderSuffix" value="]"></property>
</bean>
<!-- placeholder #[ ] for datafile.properties -->