How provided scope version works in mavan

Question

I know when provided scope define for any maven dependency ,it will provided by web server or runtime environment. But not sure how version can help here.

Take an example

<dependency>
    <groupId>org.eclipse.persistence</groupId>
    <artifactId>eclipselink</artifactId>
    <version>2.6.4</version>
    <scope>provided</scope>
</dependency>

In compile, it will use eclipselink version 2.6.4 but in runtime what will be it? Is it solely depends on the provider of the dependency while bundling it or it will depend on any other factor?

If it solely depends on the provider then what is the purpose of defining the version in provided scope? Or while defining provided scope version we should be cognizant of web server bundle version?

Answer 1

The version is to let Maven know which version of dependency should it uses when compiling the codes during packaging WAR/JAR/EAR etc.

The provided scoped is to let Maven know if it needs to include this dependency into WAR/JAR/EAR . If it is provided scoped, does not include. Otherwise , include it.

Maven will not know the version of the dependencies in your runtime environment (i.e application server) . It is the developers' responsibility to match the version specified in pom.xml to the version of the dependency of the runtime environment manually. Otherwise , you could end up with the situation like the application can actually run in the runtime environment , but since you specify a older version in pom.xml which causes you fail to package the application due to the older version does not contain the new feature classes that were introduced in the newer version.