Require Java Version
This rule enforces certain Java JDK versions. The rule uses the Enforcer version range syntax to define allowed versions.
The following parameters are supported by this rule:
- message - an optional message to the user if the rule fails.
- version - range of allowed JDKs.
- display - flag to display the normalized JDK version.
For JDK 1.8 you can also use simple
8
as version - it will be internally changed to1.8
The JDK version is retrieved and the following processing occurs before being checked:
- Drop all non-numeric characters preceding the first number. (build 1.5.0_07-b03 becomes 1.5.0_07-b03)
- Replace all '_' and '-' with '.' (1.5.0_07-b03 becomes 1.5.0.07.b03)
- Remove all non digit characters "[^0-9] and convert each section using Integer.parseInt() (1.5.0_07-b03 becomes 1.5.0.7.3)
- Split the string on '.' and take the first 3 sections, separated by '.' and add '-' followed by the fourth section (1.5.0.7.3 becomes 1.5.0-7)
This preprocessing normalizes various JDK version strings into a standard x.y.z-b version number. Your required range should therefore use the x.y.z-b format for comparison. There is an easy way to see how your current JDK string will be normalized, you can enable display option.
Sample Plugin Configuration:
<project>
[...]
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-enforcer-plugin</artifactId>
<version>3.6.0</version>
<executions>
<execution>
<id>enforce-java</id>
<goals>
<goal>enforce</goal>
</goals>
<configuration>
<rules>
<requireJavaVersion>
<version>1.6.0</version>
</requireJavaVersion>
</rules>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
[...]
</project>
If you would like to enforce a certain vendor string for the JDK, you would use the RequireJavaVendor rule