- <repositories>
 (not actually available in the main POM, but used behind the scenes) - a subset of the
 element, which consists of: 
2、激活Profiles
激活profiles有下列几种方式:
Explicitly
Through Maven settings
Based on environment variables
OS settings
Present or missing files
1)通过mvn命令的-P参数来显示激活profiles,该参数值是profile id list(之间用逗号连接)。如:
- mvn groupId:artifactId:goal -P profileId-1,profileId-2
 
				2) 通过在settings.xml里设置
- <settings>
 - ...
 - <profiles>
 - <profile>
 - <id>profile1id>
 - ...
 - profile>
 - profiles>
 - <activeProfiles>
 - <activeProfile>profile-1activeProfile>
 - activeProfiles>
 - ...
 - settings>
 
				列在
				3)Profiles还可以基于detect到的build environment 的state来自动激活,而不需要象上面2种方式显式激活。这只需要在profile定义时使用
- <profiles>
 - <profile>
 - <activation>
 - <jdk>1.4jdk>
 - activation>
 - ...
 - profile>
 - profiles>
 
上面的代码表示:如果JDK version start with 1.4 (eg. "1.4.0_08", "1.4.2_07", "1.4"),该profile会被激活
- <profiles>
 - <profile>
 - <activation>
 - <property>
 - <name>debugname>
 - property>
 - activation>
 - ...
 - profile>
 - profiles>
 
上面的代码表示:如果存在system propertie “debug”,该profile会被激活。为了激活它,输入的命令类似于:
- mvn groupId:artifactId:goal ?Ddebug
 
- <profiles>
 - <profile>
 - <activation>
 - <property>
 - <name>environmentname>
 - <value>testvalue>
 - property>
 - activation>
 - ...
 - profile>
 - profiles>
 
上面的代码表示:如果存在system propertie “environment”的值为test,该profile会被激活。为了激活它,输入的命令类似于:
- mvn groupId:artifactId:goal -Denvironment=test
 
4)Profiles还可以基于OS setting来自动激活
                


