Maven dependency scope attribute is used to specify the visibility of a dependency, relative to the different lifecycle phases (build, test, runtime etc). Maven provides six scopes i.e. compile
, provided
, runtime
, test
, system
, and import
.
Table of Contents 1. Compile Scope 2. Provided Scope 3. Runtime Scope 4. Test Scope 5. System Scope 6. Import Scope 7. Transitivity Resolution
Maven dependency scope – compile
This is maven default scope. Dependencies with compile
scope are needed to build, test, and run the project.
Scope compile
is to be required in most of the cases to resolve the import statements into your java classes sourcecode.
<dependencies> <dependency> <groupId>log4j</groupId> <artifactId>log4j</artifactId> <version>1.2.14</version> <!-- You can ommit this because it is default --> <scope>compile</scope> </dependency> </dependencies>
Maven dependency scope – provided
Maven dependency scope provided is used during build and test the project. They are also required to run, but should not exported, because the dependency will be provided by the runtime, for instance, by servlet container or application server.
<dependency> <groupId>javax.servlet</groupId> <artifactId>servlet-api</artifactId> <version>3.0.1</version> <scope>provided</scope> </dependency>
Maven dependency scope – runtime
Dependencies with maven dependency scope runtime
are not needed to build, but are part of the classpath to test and run the project.
<dependency> <groupId>com.thoughtworks.xstream</groupId> <artifactId>xstream</artifactId> <version>1.4.4</version> <scope>runtime</scope> </dependency>
Maven dependency scope – test
Dependencies with maven dependency scope test are not needed to build and run the project. They are needed to compile and run the unit tests.
<dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.12</version> <scope>test</scope> </dependency>
Maven dependency scope – system
Dependencies with system
are similar to ones with scope provided
. The only difference is system
dependencies are not retrieved from remote repository. They are present under project’s subdirectory and are referred from there. See external dependency for more detail.
<dependency> <groupId>extDependency</groupId> <artifactId>extDependency</artifactId> <scope>system</scope> <version>1.0</version> <systemPath>${basedir}\war\WEB-INF\lib\extDependency.jar</systemPath> </dependency>
Maven dependency scope – import
import
scope is only supported on a dependency of type pom
in the dependencyManagement
section. It indicates the dependency to be replaced with the effective list of dependencies in the specified POM’s dependencyManagement
section.
<dependencyManagement> <dependencies> <dependency> <groupId>other.pom.group.id</groupId> <artifactId>other-pom-artifact-id</artifactId> <version>SNAPSHOT</version> <scope>import</scope> <type>pom</type> </dependency> </dependencies> </dependencyManagement>
Maven dependency transitivity resolution
When you include a maven dependency and it has it’s own other dependencies (i.e. transitive dependencies) then you may want to be clear about the scope of these transitive dependencies as well.
Let’s understand about maven transitive dependencies with a simple table. In this table, if a dependency is set to the scope in the left column, transitive dependencies at top row will result in a dependency with the scope listed at their intersection.
Dependency | compile | provided | runtime | test |
compile | compile | – | runtime | – |
provided | provided | – | provided | – |
runtime | runtime | – | runtime | – |
test | test | – | test | – |
Drop me your questions in comments section.
Happy Learning!!
Venkata Silla
Hi,
I have 2 projects A(child) and B(parent). child project (A) is refered in project B dependency. during mvn built the child project dependency jars are not being published or defined in the lib directory of the WAR file. what is the scope i should use to get all the dependencies of the child project should be loaded in the lib directory of the WAR ?
venkat
can i use the scope to donwload dependency from other artifactory?
Annonymus
Is scope also define the phase of resolution of dependencies. Like if scope is test, then will it only resolve till maven test has done
Rani
java.lang.AbstractMethodError: javax.ws.rs.core.UriBuilder.uri(Ljava/lang/String;)Ljavax/ws/rs/core/UriBuilder;
javax.ws.rs.core.UriBuilder.fromUri(UriBuilder.java:119)
org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:291)
org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:221)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
Vipin Ahuja
Hi ,
I want some specific jars at compile/build time but don’t want to include in a final executable jar. I have used “provided” scope but that is not working. Can you please help in that .
Regards
Vipin
Lokesh Gupta
Did you unzipped the
project.jar
file to see if it has provided jars or not? You may paste you that particular dependency here, so that I can try as well.