Getting java.lang.UnsupportedClassVersionError: com/github/sdong/gradle/coverityfortify/CoverityFortifyPlugin : Unsupported major.minor version 51.0 error

I have integrated one plugin to get fortify and coverity report to my build.
i have applied plugin
apply plugin: 'com.github.sdong.gradle.coverityfortify’
classpath ‘com.github.sdong.gradle:coverityfortifyPlugin:1.1.0’ This jar is compiled using java 1.7

My machine is also configured with java 1.7.

But when i run the build using gradlew.bat clean assemble i am getting below error

 [exec] D:\build\RAS>gradlew.bat clean assemble --debug 
 [exec] Listening for transport dt_socket at address: 8005
 [exec] 18:31:24.788 [DEBUG] [org.gradle.internal.nativeintegration.services.NativeServices] Native-platform posix files is not available.  Continuing with fallback.
 [exec] 18:31:24.819 [DEBUG] [org.gradle.internal.nativeintegration.filesystem.services.FileSystemServices] Unable to load org.gradle.internal.nativeintegration.filesystem.jdk7.WindowsJdk7Symlink. Continuing with fallback org.gradle.internal.nativeintegration.filesystem.services.WindowsSymlink.
 **[exec] 18:31:26.144 [WARN] [org.gradle.internal.featurelifecycle.LoggingDeprecatedFeatureHandler] Support for running Gradle using Java 6 has been deprecated and will be removed in Gradle 3.0**

*** What went wrong:**
** [echo] A problem occurred evaluating root project ‘RAS’.**
** [echo] > java.lang.UnsupportedClassVersionError: com/github/sdong/gradle/coverityfortify/CoverityFortifyPlugin : Unsupported major.minor version 51.0**

Is the warning Support for running Gradle using Java 6 has been deprecated and will be removed in Gradle 3.0 causing problem ??? if yes how to remove that warning. ?

You are running Gradle on Java 6. I guess either you have set your JAVA_HOME to point to Java 6 or you have set it in your ~/.gradle/gradle.properties.