使用Spring(在XML中进行显式连接，自动装配或它们的某种组合)来定义常量"配置，然后将其余部分外部化到属性文件中.数据库凭证是这种情况的常见示例.

Use Spring, being explicit wiring in XML, auto-wiring or some combination thereof, to define "constant" config and then externalize the rest in properties files. Database credentials are a common example of this.

有关基准，请参见 Spring和Ibatis教程这个例子.简短版本:

See Spring and Ibatis Tutorial for a baseline example of this. Short version:

<bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
    <property name="location" value="classpath:database.properties"/>
</bean>

<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
    <property name="driverClassName" value="${database.class}"/>
    <property name="url" value="${database.url}"/>
    <property name="username" value="${database.username}"/>
    <property name="password" value="${database.password}"/>
</bean>

with database.properties(在类路径中):

with database.properties (in the classpath):

database.username=scratch
database.password=scratch
database.class=oracle.jdbc.OracleDriver
database.url=jdbc:oracle:thin:@localhost:1521:XE