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Posted to commits@maven.apache.org by jv...@apache.org on 2005/10/13 12:54:24 UTC
svn commit: r320722 -
/maven/components/trunk/maven-site/src/site/apt/guides/introduction/introduction-to-dependency-mechanism.apt.txt
Author: jvanzyl
Date: Thu Oct 13 03:54:20 2005
New Revision: 320722
URL: http://svn.apache.org/viewcvs?rev=320722&view=rev
Log:
o finished converting APT for dep mechanism
Modified:
maven/components/trunk/maven-site/src/site/apt/guides/introduction/introduction-to-dependency-mechanism.apt.txt
Modified: maven/components/trunk/maven-site/src/site/apt/guides/introduction/introduction-to-dependency-mechanism.apt.txt
URL: http://svn.apache.org/viewcvs/maven/components/trunk/maven-site/src/site/apt/guides/introduction/introduction-to-dependency-mechanism.apt.txt?rev=320722&r1=320721&r2=320722&view=diff
==============================================================================
--- maven/components/trunk/maven-site/src/site/apt/guides/introduction/introduction-to-dependency-mechanism.apt.txt (original)
+++ maven/components/trunk/maven-site/src/site/apt/guides/introduction/introduction-to-dependency-mechanism.apt.txt Thu Oct 13 03:54:20 2005
@@ -12,148 +12,99 @@
There are many aspects to working with dependencies in Maven. While it is not the sole focus of Maven, it
does comprise a large and important part of the system. Learn more about:
- <ul>
- <li>
- <a href="#transitive_dependencies">Transitive Dependencies</a>
- </li>
- <li>
- <a href="#dependency_scope">Dependency Scope</a>
- </li>
- <li>
- <a href="#dependency_management">Dependency Management</a>
- </li>
- </ul>
- </p>
- <p>
- <i>This document is currently in the process of being written, so not all facets are covered.</i>
- </p>
- <a name="transitive_dependencies"/>
- <subsection name="Transitive Dependencies">
- <p>
- Transitive dependencies are a new feature in Maven 2.0. This allows you to avoid needing to discover and
- specify the libraries that your own dependencies require, and including them automatically.
- </p>
- <p>
- This feature is facilitated by reading the project files of your dependencies from the remote repositories
- specified. In general, all dependencies of those projects are used in your project, as are any that the
- project inherits from its parents, or from its dependencies, and so on.
- </p>
- <p>
- There is no limit to the number of levels that dependencies can be gathered from, and will only cause a
- problem
- if a cyclic dependency is discovered.
- </p>
- <p>
- With transitive dependencies, the graph of included libraries can quickly grow quite large. For this reason,
- there are some additional features that will limit which dependencies are included:
- </p>
- <ul>
- <li>
- <i>Dependency mediation</i>
- - this determines what version of a dependency will be used when multiple
- versions of an artifact are encountered. Currently, Maven 2.0 only supports using the "nearest definition" - so
- you can always guarantee a version by declaring it explicitly in your project's POM.
- </li>
- <li>
- <i>Dependency scope</i>
- - this allows you to only include dependencies appropriate for the current stage
- of the build. This is described in more detail below.
- </li>
- </ul>
- </subsection>
- <subsection name="Dependency Scope">
- <a name="dependency_scope"/>
- <p>
- Dependency scope is used to limit the transitivity of a depedency, and also to affect the classpath used for
- various build tasks.
- </p>
- <p>
- There are 4 scopes available:
- </p>
- <ul>
- <li>
- <b>compile</b>
- - this is the default scope, used if none is specified. Compile dependencies are available
- in all classpaths.
- </li>
- <li>
- <b>provided</b>
- - this is much like compile, but indicates you expect the JDK or a container to provide it.
- It is only available on the compilation classpath, and is not transitive.
- </li>
- <li>
- <b>runtime</b>
- - this scope indicates that the dependency is not required for compilation, but is for
- execution.
- It is in the runtime and test classpaths, but not the compile classpath.
- </li>
- <li>
- <b>test</b>
- - this scope indicates that the dependency is not required for normal use of the application, and
- is only available for the test compilation and execution phases.
- </li>
- </ul>
- <p>
- Each of the scopes affects transitive dependencies in different ways, as is demonstrated in the table below.
- If a dependency is set to the scope in the left column, dependencies with the scope across the top row will
- result in a dependency in the main project with the scope listed at the intersection. If no scope is listed,
- it means the dependency will be omitted.
- </p>
- <table>
- <tr>
- <th></th>
- <th>compile</th>
- <th>provided</th>
- <th>runtime</th>
- <th>test</th>
- </tr>
- <tr>
- <th>compile</th>
- <td>compile (*)</td>
- <td>-</td>
- <td>runtime</td>
- <td>-</td>
- </tr>
- <tr>
- <th>provided</th>
- <td>provided</td>
- <td>provided</td>
- <td>provided</td>
- <td>-</td>
- </tr>
- <tr>
- <th>runtime</th>
- <td>runtime</td>
- <td>-</td>
- <td>runtime</td>
- <td>-</td>
- </tr>
- <tr>
- <th>test</th>
- <td>test</td>
- <td>-</td>
- <td>test</td>
- <td>-</td>
- </tr>
- </table>
- <p>
- <b>(*) Note:</b>
- it is intended that this should be runtime instead, so that all compile dependencies must
- be explicitly listed - however, there is the case where the library you depend on extends a class from another
- library, forcing you to have available at compile time. For this reason, compile time dependencies remain
- as compile scope even when they are transitive.
- </p>
- </subsection>
- <a name="dependency_management"/>
- <subsection name="Dependency Management">
- <p>
- The dependency management section is a mechanism for centralizing dependency information. When you have
- a set of projects that inherits a common parent it's possible to put all information about the dependency
- in the common POM and have simpler references to the artifacts in the child POMs. The mechanism is best
- illustrated through some examples. Given these two POMs which extend the same parent:
- </p>
- <p>
- Project A:
+ * Transitive Dependencies
+
+ * Dependency Scope
+
+ * Dependency Management
+
+ []
+
+ <<NOTE:>> <This document is currently in the process of being written, so not all facets are covered.>
+
+* Transitive Dependencies">
+
+ Transitive dependencies are a new feature in Maven 2.0. This allows you to avoid needing to discover and
+ specify the libraries that your own dependencies require, and including them automatically.
+
+ This feature is facilitated by reading the project files of your dependencies from the remote repositories
+ specified. In general, all dependencies of those projects are used in your project, as are any that the
+ project inherits from its parents, or from its dependencies, and so on.
+
+ There is no limit to the number of levels that dependencies can be gathered from, and will only cause a
+ problem if a cyclic dependency is discovered.
+
+ With transitive dependencies, the graph of included libraries can quickly grow quite large. For this reason,
+ there are some additional features that will limit which dependencies are included:
+
+ * <Dependency mediation>
+ - this determines what version of a dependency will be used when multiple
+ versions of an artifact are encountered. Currently, Maven 2.0 only supports using the "nearest definition" - so
+ you can always guarantee a version by declaring it explicitly in your project's POM.
+
+ * <Dependency scope>
+ - this allows you to only include dependencies appropriate for the current stage
+ of the build. This is described in more detail below.
+
+ []
+
+* Dependency Scope
+
+ Dependency scope is used to limit the transitivity of a depedency, and also to affect the classpath used for
+ various build tasks.
+
+ There are 4 scopes available:
+
+ * <<compile>>
+ - this is the default scope, used if none is specified. Compile dependencies are available
+ in all classpaths.
+
+ * <<provided>>
+ - this is much like compile, but indicates you expect the JDK or a container to provide it.
+ It is only available on the compilation classpath, and is not transitive.
+
+ * <<runtime>>
+ - this scope indicates that the dependency is not required for compilation, but is for
+ execution. It is in the runtime and test classpaths, but not the compile classpath.
+
+ * <<test>>
+ - this scope indicates that the dependency is not required for normal use of the application, and
+ is only available for the test compilation and execution phases.
+
+ []
+
+ Each of the scopes affects transitive dependencies in different ways, as is demonstrated in the table below.
+ If a dependency is set to the scope in the left column, dependencies with the scope across the top row will
+ result in a dependency in the main project with the scope listed at the intersection. If no scope is listed,
+ it means the dependency will be omitted.
+
+*----------+------------+----------+----------+------+
+| | compile | provided | runtime | test
+*----------+------------+----------+----------+------+
+| compile | compile(*) | - | runtime | -
+*----------+------------+----------+----------+------+
+| provided | provided | provided | provided | -
+*----------+------------+----------+----------+------+
+| runtime | runtime | - | runtime | _
+*----------+------------+----------+----------+------+
+| test | test | - | test | -
+*----------+------------+----------+----------+------+
+
+ <<(*) Note:>>
+ it is intended that this should be runtime instead, so that all compile dependencies must
+ be explicitly listed - however, there is the case where the library you depend on extends a class from another
+ library, forcing you to have available at compile time. For this reason, compile time dependencies remain
+ as compile scope even when they are transitive.
+
+* Dependency Management
+
+ The dependency management section is a mechanism for centralizing dependency information. When you have
+ a set of projects that inherits a common parent it's possible to put all information about the dependency
+ in the common POM and have simpler references to the artifacts in the child POMs. The mechanism is best
+ illustrated through some examples. Given these two POMs which extend the same parent:
+
+ Project A:
+
+----+
<project>
@@ -207,8 +158,9 @@
</project>
+----+
- These two example POMs share a common dependency and each has one non-trivial dependency. This information
- can be put in the parent POM like this:
+
+ These two example POMs share a common dependency and each has one non-trivial dependency. This information
+ can be put in the parent POM like this:
+----+
@@ -286,4 +238,4 @@
+----+
The reference information about the dependency management tags is available from the
- {{{maven-model/maven.html#class_DependencyManagement}project descriptor reference}}.
+ {{{maven-model/maven.html#class_DependencyManagement}project descriptor reference}}.
\ No newline at end of file