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~~ under the License.    
 
  ------
  Require Property
  ------
  Brian Fox
  ------
  June 2007
  ------

Require Property

  This rule can enforce that a declared property is set and optionally evaluate it against a regular expression.

  The following parameters are supported by this rule:
   
  * property - the property to evaluate.
   
  * message - an optional message to the user if the rule fails. Default is: "Property 'xxx' is required for this build".	
   
  * regex - a regular expression used to check the value of the property.
   
  * regexMessage - an optional message to the user if the regex check fails.

  []

  The regex is applied to the entire value of the property (i.e. using the regex "match" method),
  and not just a substring of the property value.

  Sample Plugin Configuration:
  
+---+
<project>
  [...]
  <build>
    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-enforcer-plugin</artifactId>
        <version>${project.version}</version>
        <executions>
          <execution>
            <id>enforce-property</id>
            <goals>
              <goal>enforce</goal>
            </goals>
            <configuration>
              <rules>
                <requireProperty>
                  <property>basedir</property>
                  <message>You must set a basedir property!</message>
                  <regex>.*\d.*</regex>
                  <regexMessage>The basedir property must contain at least one digit.</regexMessage>
                </requireProperty>
                <requireProperty>
                  <property>project.version</property>
                  <message>"Project version must be specified."</message>
                  <regex>.*(\d|-SNAPSHOT)$</regex>
                  <regexMessage>"Project version must end in a number or -SNAPSHOT."</regexMessage>
                </requireProperty>
              </rules>
              <fail>true</fail>
            </configuration>
          </execution>
        </executions>
      </plugin>
    </plugins>
  </build>
  [...]
</project>
+---+