Maven-Sling-Plugin requires Java 8

When using the maven sling plugin 2.3.4 with Java 7, the following error occurs:

[ERROR] Failed to execute goal org.apache.sling:maven-sling-plugin:2.3.4:generate-adapter-metadata (generate-adapter-metadata) on project org.apache.sling.resourceresolver: Execution generate-adapter-metadata of goal org.apache.sling:maven-sling-plugin:2.3.4:generate-adapter-metadata failed: An API incompatibility was encountered while executing org.apache.sling:maven-sling-plugin:2.3.4:generate-adapter-metadata: java.lang.UnsupportedClassVersionError: javax/json/JsonException : Unsupported major.minor version 52.0
[ERROR] -----------------------------------------------------
[ERROR] realm =    plugin>org.apache.sling:maven-sling-plugin:2.3.4
[ERROR] strategy = org.codehaus.plexus.classworlds.strategy.SelfFirstStrategy
[ERROR] urls[0] = file:/Users/cziegeler/.m2/repository/org/apache/sling/maven-sling-plugin/2.3.4/maven-sling-plugin-2.3.4.jar
[

Reverting to version 2.3.2 fixes the problem