Make your objects testable.
'br.com.objectos:testable-guava:0.2.0'
<dependency>
<groupId>br.com.objectos</groupId>
<artifactId>testable-guava</artifactId>
<version>0.2.0</version>
</dependency>
<dependency org="br.com.objectos" name="testable-guava" rev="0.2.0"/>
"br.com.objectos", "testable-guava", "0.2.0"