Multiple DataSource configurations using Spring

While developing Java based applications we might frequently need to change the database properties based on the environment we are working like PRODUCTION, DEVELOPMENT OR UAT environments. In that situations the following approach will be useful and easy to configure database properties for each environment.

If we want to change the environment we just need to change the ENV property value.

<bean id="placeholderConfigurer" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
      <property name="ignoreResourceNotFound" value="true"></property>
      <property name="ignoreUnresolvablePlaceholders" value="true"></property>
      <property name="nullValue" value="NULL"></property>
      <property name="locations">
<list>
<value>jdbc.properties</value>
</list>
</property>
</bean>

<bean id="dataSource" class="com.spring.dao.JDBCConfig">
<property name="driverClassName" value="${${Env}.jdbc.driverClassName}"></property>
<property name="url" value="${${Env}.jdbc.url}"></property>
<property name="username" value="${${Env}.jdbc.username1}"></property>
<property name="password" value="${${Env}.jdbc.password}"></property>
</bean>


jdbc.properties
*****************************
Env=PROD

jdbc.driverClassName=${${Env}.jdbc.driverClassName}
jdbc.url=${${Env}.jdbc.url}
jdbc.username=${${Env}.jdbc.username}
jdbc.password=${${Env}.jdbc.password}


######### JDBC Configuration for DEV Environment ###############
DEV.jdbc.driverClassName=com.mysql.jdbc.Driver
DEV.jdbc.url=jdbc:mysql://localhost:3306/devportal
DEV.jdbc.username=DEVuser
DEV.jdbc.password=DEVpwd

######### JDBC Configuration for UAT Environment ############
UAT.jdbc.driverClassName=com.mysql.jdbc.Driver
UAT.jdbc.url=jdbc:mysql://localhost:3306/UATportal
UAT.jdbc.username=UATuser
UAT.jdbc.password=UATpwd

########## JDBC Configuration for PROD Environment ############
PROD.jdbc.driverClassName=com.mysql.jdbc.Driver
PROD.jdbc.url=jdbc:mysql://localhost:3306/portal
PROD.jdbc.username=root
PROD.jdbc.password=admin