In Maven, properties are used to customise the behaviour of Maven and its plugins.
Maven supports a hierarchy of different properties to allow specifying defaults and overriding them at the appropriate level.
The properties files in Maven are processed in the following order:
PDF Documentation${basedir}/project.properties (basedir is replaced by the directory where the project.xml file in use resides)${basedir}/build.properties${user.home}/build.properties
The built-in properties are specified in the plugin.properties file of a plugin, or in
defaults.properties within Maven itself.
Both the project.properties and build.properties files in the project
directory are also inherited along with the related project.xml file.
The last definition takes precedence, so ${user.home}/build.properties will override
anything specified in a project, and properties given on the command line using -D will
override everything.
Note: there are no per-user defaults, as there has not been a property shown where this concept makes sense. Currently, there are also no site-wide defaults, however this is planned for future versions of Maven.
The following table explains how each file should be used.
${basedir}/project.properties |
These are properties specific to the project and can be used to set the values for plugin and Maven properties that are appropriate for that project. This file should be checked into your source repository and distributed. |
${basedir}/build.properties |
These are properties specific to the project, but also the user running it. It is for
overriding values in the project.properties for this user only.
It should not be checked into the source repository. If a user is required to
set any of these properties for a build to run properly, a build.properties.sample
file should be created and checked into the source repository as a courtesy.
|
${user.home}/build.properties |
These are properties specific to the user but shared among all projects. This typically specifies remote repositories to download from and upload to, proxy settings, file system locations, and so on. |
The following properties are built-in to Maven and apply to all projects.
| Property | Description | Default Value |
|---|---|---|
maven.home.local |
The directory on the local machine Maven uses to write user specific details to, such as expanded plugins and cache data. | ${user.home}/.maven |
maven.plugin.dir |
Where Maven can find it's plugins. | ${maven.home}/plugins |
maven.plugin.user.dir |
Where Maven can find plugins for this user only. | ${maven.home.local}/plugins |
maven.plugin.unpacked.dir |
Where Maven expands installed plugins for processing. | ${maven.home.local}/cache |
maven.repo.local |
The repository on the local machine Maven should use to store downloaded artifacts (jars etc). | ${maven.home.local}/repository |
| Property | Description | Default Value |
|---|---|---|
basedir |
This is the base directory of the currently building project. It is an absolute path. | - |
maven.build.dir |
The directory where generated output, e.g. class files, documentation, unit test reports etc goes. | ${basedir}/target |
maven.build.dest |
The directory where generated classes go. | ${maven.build.dir}/classes |
maven.build.src |
The directory where generated source goes. DEPRECATED: Currently unused. There is no replacement - any plugin generating source has it's own specific property. | ${maven.build.dir}/src |
maven.conf.dir |
The directory that holds configuration files.
DEPRECATED: Currently unused. Instead, use the <resources>
element of the POM.
|
${basedir}/conf |
maven.src.dir |
The base directory for source code.
Note that this should contain all source directories
(<sourceDirectory>, <unitTestSourceDirectory>, etc.)
defined in the POM.
|
${basedir}/src |
| Property | Description | Default Value |
|---|---|---|
maven.docs.dest |
The output directory for the generated HTML for the site documentation. | ${maven.build.dir}/docs |
maven.docs.omitXmlDeclaration |
Whether generated documentation should have an xml declaration, e.g.
<?xml version="1.0"?> |
false |
maven.docs.outputencoding |
The character encoding for generated documentation. | ISO-8859-1 |
maven.docs.src |
The directory for user supplied documentation. | ${basedir}/xdocs |
maven.gen.docs |
The directory where generated xdocs that need to be transformed to HTML are placed. | ${maven.build.dir}/generated-xdocs |
Please refer to Working with Repositories for more information.
| Property | Description | Default Value |
|---|---|---|
maven.mode.online |
Whether you are connected to the internet or not. | true |
maven.repo.remote |
The repository maven should use to download artifacts (jars etc) that it can't find in the local repository. You should set this to one of the repo mirrors. You can also specify multiple repositories, separated by commas. | http://repo1.maven.org/maven/ |
maven.repo.remote.enabled |
Whether or not a remote repository should be used. | true |
If you do require a proxy, the most appropriate place to set these
values would be in your ${user.home}/build.properties
file.
| Property | Description | Default Value |
|---|---|---|
maven.proxy.host |
The IP or address of your proxy. | - |
maven.proxy.port |
The port number of your proxy. | - |
maven.proxy.username |
User name if your proxy requires authentication. | - |
maven.proxy.password |
Password if your proxy requires authentication. | - |
maven.proxy.ntlm.host |
The host to use if you are using NTLM authentication. | - |
maven.proxy.ntlm.domain |
The NT domain to use if you are using NTLM authentication. | - |
DEPRECATED: The following have all been deprecated in favour of using the relevant elements in the POM, and the properties of the artifact plugin.
| Property | Description | Default Value |
|---|---|---|
maven.repo.central |
This is the host that Maven will attempt to deploy to. This is deprecated in
favour of distributionSite and siteAddress.
|
- |
maven.repo.central.directory |
This is the directory that Maven will attempt to deploy to. This is deprecated in
favour of distributionDirectory and siteDirectory.
|
- |
maven.scp.executable |
The executable to use for secure copies. | scp |
maven.ssh.executable |
The executable to use for executing commands remotely. | ssh |
maven.username |
The remote username to log in as when deploying. | - |
maven.remote.group |
The group to set the artifact to once deployed. | maven |
Each plugin has a set of built in properties. For a reference of these properties, you can find a "Properties" link in the left hand navigation of the plugin documentation of each individual plugin.