Question

I have a Java EE 6 app that I build with Maven, code in NetBeans 7 and deploy on GlassFish 3.1.2. As I near completion, I find myself deploying demo builds.

The problem is that I don’t have any dead easy way to build for different environment such as dev, QA, demo, prod, etc. For some stuff, I’ve been using a Java class with a bunch of static getters that return values based on the value of an environment constant. But this doesn’t help me with conditionally setting

• javax.faces.PROJECT_STAGE (web.xml)
• database credentials (glassfish-resources.xml)
• mail servers (glassfish-resources.xml)
• JPA logging level (persistence.xml)

and probably a number of other things I can’t think about now that are scattered across XML files.

Is there any way to define multiple versions of these configuration files and just set a flag at build time to select the environment, while defaulting to dev when no environment is specified? Is there a way I could make Maven work for me in this instance?

Answer 1

You can use maven to achieve that. Especially using resource filtering.

First, you can define list of profiles:

  <profiles>
    <profile>
      <id>dev</id>
      <properties>
        <env>development</env>
      </properties>
      <activation>
        <activeByDefault>true</activeByDefault> <!-- use dev profile by default -->
      </activation>
    </profile>
    <profile>
      <id>prod</id>
      <properties>
        <env>production</env>
      </properties>
    </profile>
  </profiles>

Then the resources that you need to filter:

  <build>
    <outputDirectory>${basedir}/src/main/webapp/WEB-INF/classes</outputDirectory>
    <filters>
      <filter>src/main/filters/filter-${env}.properties</filter> <!-- ${env} default to "development" -->
    </filters>
    <resources>
      <resource>
        <directory>src/main/resources</directory>
        <includes>
          <include>**/*.xml</include>
          <include>**/*.properties</include>
        </includes>
        <filtering>true</filtering>
      </resource>
    </resources>
  </build>

And then your custom properties based on profiles in src/main/filters directory:

filter-development.properties

# profile for developer
db.driver=org.hsqldb.jdbcDriver
db.url=jdbc:hsqldb:mem:web

and

filter-production.properties

# profile for production
db.driver=com.mysql.jdbc.Driver
db.url=jdbc:mysql://localhost:3306/web?createDatabaseIfNotExist=true

to use production profile, you can package war using mvn clean package -Pprod command.

Here you can see the sample project that use profile in maven.