Best way to extract DataBase connection settings to external file in Java EE Maven project

Question

On my local machine I am creating Java EE Maven project on Tomcat7 that collaborates with local MySQL database.

For now I have all db connection settings like (user, password, host, dbname, ... etc) hardcoded in DatabaseQueries.java directly in Java EE Maven project, but I know it is not right and I want to take out this setting from project for example to db.properties file, so when I deploy the project on my remote Tomcat7 server it will use different db.properties file with corresponing settings or if I share the project in GitHub, other people will not see my db username and password.

Thus I have few questions:

1. What is the best practice of externalizing the db settings from Maven project ?

2. Does Maven project has already build-in functionality to do this ?

3. How to be sure, that when I export a project as a *.WAR file it will not include this db.properties file ?

4. Is it correct to use the name as "db.properties" for this purposes ?

Answer 1

For example , in your project add 4 folders :

1. Your Project\src\main\resources\

   \local > db.properties
   \integration > db.properties
   \deploy > db.properties
   \Default > db.properties
   

2. in pom.xml add :

    <properties>
        <param>Default</param>
    </properties>
   

   and

    <build>
        <resources>
            <resource>
                <directory>src/main/resources/${param}</directory>           
            </resource>
        </resources>
    </build> 
   
    if : mvn clean install   : classpath => db.properties(from Default)
   
    if : mvn clean install -Dparam=local : classpath => db.properties(from local)
   
    if : mvn clean install -Dparam=integration : classpath => db.properties(from integration)
   
    if : mvn clean install -Dparam=deploy : classpath => db.properties(from deploy)
   

Much better than using profiles is more extensible without touching the pom.