This plugin changes getters for properties that are not optional singletons in an XSD file (minOccurs = 0 and maxOccurs = 1) to return an Optional value.
Example use in Maven when building with the maven-jaxb2-plugin:
<build>
<plugins>
<plugin>
<groupId>org.jvnet.jaxb2.maven2</groupId>
<artifactId>maven-jaxb2-plugin</artifactId>
<version>LATEST</version>
<executions>
<execution>
<id>xsd-generate</id>
<phase>generate-sources</phase>
<goals>
<goal>generate</goal>
</goals>
</execution>
</executions>
<configuration>
<extension>true</extension>
<args>
<arg>-Xnullsafegetters</arg>
</args>
<plugins>
<plugin>
<groupId>codes.rafael.xjc</groupId>
<artifactId>nullsafe</artifactId>
<version>LATEST</version>
</plugin>
</plugins>
</configuration>
</plugin>
</plugins>
</build>Under the Apache 2.0 license.