Question

My servlet.xml file holds all my spring configuration related information like datasource bean etc.

<bean id="..." class="...">
</bean>

Now my application has other settings that I need to save in a configuration file, is it possible to create my own settings in here or is there a better way?

I want something that loads up once and is very fast to reference in my project.

I need this to store some file paths, and other database settings for things like mongodb etc.

Answer 1

You can use .properties file:

<context:property-placeholder location="file:///my/cfg.properties"/>

If the file contents are:

driver=com.mysql.jdbc.Driver
dbname=mysql:mydb
mysetting=42

You can reference them in Spring XML like this:

<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
 <property name="driverClassName"><value>${driver}</value></property>
 <property name="url"><value>jdbc:${dbname}</value></property>
</bean>

Reference: 4.8.2.1 Example: the PropertyPlaceholderConfigurer.

You can also inject these properties into your own classes:

@Service
public class MyService {
    @Value("${mysetting}")
    private int mysetting;  //Spring will inject '42' on bean creation

    //...
}

Of course you can also use setter-injection like in the example with DriverManagerDataSource if you prefer XML.

Also have a look at: Spring 3.1 M1: Unified Property Management.