Typesafe's Activator Spray template does not work due to UnsupportedClassVersionError

[nataren]

Steps to reproduce:

1. Install activator-0.3.0 from typesafe.com
2. Run it
3. Visit http://localhost:8888/home once the Activator is running
4. Click "Show all 24 templates"
5. Choose the Spray filter
6. Choose the "Akka and Spray" template
7. Choose an app name.
8. Choose a location
9. Click Create
10. Confirm you get a "Your application is being created ..."
11. Click the Run tab and click Start.
12. Confirm an error happened.

The log shows:

Build succeeded, running...
Set current project to mySprayApp (in build file:/Users/cesar/mySprayApp/)
Reapplying settings...
Set current project to mySprayApp (in build file:/Users/cesar/mySprayApp/)
Running task... Cancelable: false, check cycles: false
Initial source changes: removed:Set() added: Set() modified: Set() Removed products: Set() Modified external sources: Set() Modified binary dependencies: Set() Initial directly invalidated sources: Set() Sources indirectly invalidated by: product: Set() binary dep: Set() external source: Set()
All initially invalidated sources: Set()
Copy resource mappings: (/Users/cesar/mySprayApp/src/main/resources/application.conf,/Users/cesar/mySprayApp/target/scala-2.10/classes/application.conf)
Running Cli
Starting sandboxed run...
Waiting for threads to exit or System.exit to be called.
Classpath: /Users/cesar/mySprayApp/target/scala-2.10/classes /Users/cesar/.sbt/boot/scala-2.10.2/lib/scala-library.jar /Users/cesar/.ivy2/cache/com.typesafe.akka/akka-actor_2.10/jars/akka-actor_2.10-2.2.0.jar /Users/cesar/.ivy2/cache/com.typesafe/config/bundles/config-1.0.2.jar /Users/cesar/.ivy2/cache/com.typesafe.akka/akka-slf4j_2.10/bundles/akka-slf4j_2.10-2.2.0.jar /Users/cesar/.ivy2/cache/ch.qos.logback/logback-classic/jars/logback-classic-1.0.13.jar /Users/cesar/.ivy2/cache/ch.qos.logback/logback-core/jars/logback-core-1.0.13.jar /Users/cesar/.ivy2/cache/org.slf4j/slf4j-api/jars/slf4j-api-1.7.5.jar /Users/cesar/.ivy2/cache/io.spray/spray-can/jars/spray-can-1.2-20130712.jar /Users/cesar/.ivy2/cache/io.spray/spray-io/jars/spray-io-1.2-20130712.jar /Users/cesar/.ivy2/cache/io.spray/spray-util/jars/spray-util-1.2-20130712.jar /Users/cesar/.ivy2/cache/io.spray/spray-http/jars/spray-http-1.2-20130712.jar /Users/cesar/.ivy2/cache/org.parboiled/parboiled-scala_2.10/bundles/parboiled-scala_2.10-1.1.5.jar /Users/cesar/.ivy2/cache/org.parboiled/parboiled-core/bundles/parboiled-core-1.1.5.jar /Users/cesar/.ivy2/cache/io.spray/spray-routing/jars/spray-routing-1.2-20130712.jar /Users/cesar/.ivy2/cache/io.spray/spray-httpx/jars/spray-httpx-1.2-20130712.jar /Users/cesar/.ivy2/cache/org.jvnet.mimepull/mimepull/jars/mimepull-1.9.2.jar /Users/cesar/.ivy2/cache/com.chuusai/shapeless_2.10/jars/shapeless_2.10-1.2.4.jar /Users/cesar/.ivy2/cache/io.spray/spray-json_2.10/jars/spray-json_2.10-1.2.3.jar
Waiting for thread run-main to exit
(run-main) java.lang.UnsupportedClassVersionError: Cli : Unsupported major.minor version 51.0
Cli : Unsupported major.minor version 51.0
Thread run-main exited.
Interrupting remaining threads (should be all daemons).
Sandboxed run complete..
Nonzero exit code: 1
(compile:run-main) Nonzero exit code: 1
Total time: 0 s, completed Sep 2, 2013 1:54:20 PM
Failed: error: exception during sbt task: run-main: Incomplete: null

[jrudolph]

This means you've got some artifacts lying around which were compiled with Java 7 and you try to run them with Java 6, hard to say which exactly.

[d1egoaz]

I have no problems with the template. activator 0.3.0

~|⇒ java -version
java version "1.7.0_17"
Java(TM) SE Runtime Environment (build 1.7.0_17-b02)
Java HotSpot(TM) 64-Bit Server VM (build 23.7-b01, mixed mode)

[janm399]

Do you have JDK 1.6 installed alongside 1.7? (It's not a problem, of course.) What's your $JAVA_HOME variable set to?

$ echo $JAVA_HOME

On my machine, it is /Library/Java/JavaVirtualMachines/jdk1.7.0_25.jdk/Contents/Home.

[nataren]

echo $JAVA_HOME
/System/Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents/Home