java.lang.UnsupportedClassVersionError: com/typesafe/config/ConfigException : Unsupported major.minor version 52.0

java.lang.UnsupportedClassVersionError: com/typesafe/config/ConfigException : Unsupported major.minor version 52.0
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClass(ClassLoader.java:800)
    at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
    at java.net.URLClassLoader.defineClass(URLClassLoader.java:449)
    at java.net.URLClassLoader.access$100(URLClassLoader.java:71)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
    at com.typesafe.sbt.web.SbtWeb$$anonfun$com$typesafe$sbt$web$SbtWeb$$load$1.apply(SbtWeb.scala:535)
    at com.typesafe.sbt.web.SbtWeb$$anonfun$com$typesafe$sbt$web$SbtWeb$$load$1.apply(SbtWeb.scala:535)
    at scala.Option.fold(Option.scala:157)
    at com.typesafe.sbt.web.SbtWeb$.com$typesafe$sbt$web$SbtWeb$$load(SbtWeb.scala:549)
    at com.typesafe.sbt.web.SbtWeb$$anonfun$globalSettings$1$$anonfun$apply$1.apply(SbtWeb.scala:143)
    at com.typesafe.sbt.web.SbtWeb$$anonfun$globalSettings$1$$anonfun$apply$1.apply(SbtWeb.scala:143)
    at scala.Function1$$anonfun$andThen$1.apply(Function1.scala:55)
    at sbt.Project$.setProject(Project.scala:319)
    at sbt.BuiltinCommands$.doLoadProject(Main.scala:484)
    at sbt.BuiltinCommands$$anonfun$loadProjectImpl$2.apply(Main.scala:475)
    at sbt.BuiltinCommands$$anonfun$loadProjectImpl$2.apply(Main.scala:475)
    at sbt.Command$$anonfun$applyEffect$1$$anonfun$apply$2.apply(Command.scala:58)
    at sbt.Command$$anonfun$applyEffect$1$$anonfun$apply$2.apply(Command.scala:58)
    at sbt.Command$$anonfun$applyEffect$2$$anonfun$apply$3.apply(Command.scala:60)
    at sbt.Command$$anonfun$applyEffect$2$$anonfun$apply$3.apply(Command.scala:60)
    at sbt.Command$.process(Command.scala:92)
    at sbt.MainLoop$$anonfun$1$$anonfun$apply$1.apply(MainLoop.scala:98)
    at sbt.MainLoop$$anonfun$1$$anonfun$apply$1.apply(MainLoop.scala:98)
    at sbt.State$$anon$1.process(State.scala:184)
    at sbt.MainLoop$$anonfun$1.apply(MainLoop.scala:98)
    at sbt.MainLoop$$anonfun$1.apply(MainLoop.scala:98)
    at sbt.ErrorHandling$.wideConvert(ErrorHandling.scala:17)
    at sbt.MainLoop$.next(MainLoop.scala:98)
    at sbt.MainLoop$.run(MainLoop.scala:91)
    at sbt.MainLoop$$anonfun$runWithNewLog$1.apply(MainLoop.scala:70)
    at sbt.MainLoop$$anonfun$runWithNewLog$1.apply(MainLoop.scala:65)
    at sbt.Using.apply(Using.scala:24)
    at sbt.MainLoop$.runWithNewLog(MainLoop.scala:65)
    at sbt.MainLoop$.runAndClearLast(MainLoop.scala:48)
    at sbt.MainLoop$.runLoggedLoop(MainLoop.scala:32)
    at sbt.MainLoop$.runLogged(MainLoop.scala:24)
    at sbt.StandardMain$.runManaged(Main.scala:53)
    at sbt.xMain.run(Main.scala:28)
    at xsbt.boot.Launch$$anonfun$run$1.apply(Launch.scala:109)
    at xsbt.boot.Launch$.withContextLoader(Launch.scala:128)
    at xsbt.boot.Launch$.run(Launch.scala:109)
    at xsbt.boot.Launch$$anonfun$apply$1.apply(Launch.scala:35)
    at xsbt.boot.Launch$.launch(Launch.scala:117)
    at xsbt.boot.Launch$.apply(Launch.scala:18)
    at xsbt.boot.Boot$.runImpl(Boot.scala:41)
    at xsbt.boot.Boot$.main(Boot.scala:17)
    at xsbt.boot.Boot.main(Boot.scala)
[error] java.lang.UnsupportedClassVersionError: com/typesafe/config/ConfigException : Unsupported major.minor version 52.0
[error] Use 'last' for the full log.

solution:

Still you are using java7. You can download java8. If you already install java8 make sure it is active.You can change java version using bellow commands.

How To Change Java Version 

 

$ sudo update-alternatives --config java

There are 2 choices for the alternative java (providing /usr/bin/java).

  Selection    Path                                            Priority   Status
------------------------------------------------------------
* 0            /usr/lib/jvm/java-7-openjdk-amd64/jre/bin/java   1061      auto mode
  1            /usr/lib/jvm/java-7-openjdk-amd64/jre/bin/java   1061      manual mode
  2            /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/java   1051      manual mode

Press enter to keep the current choice[*], or type selection number: 2

update-alternatives: using /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/java
to provide /usr/bin/java (java) in manual mode

 

 Now you can check you java version using below command

java -version