プレイフレームワークの実行中にサポートされていないmajor.minorバージョン51.0

Question

バージョンの競合があります。誰かに私にそれを解決する方法を教えてもらいたい。以前のstackoverflow投稿では誰も解決策を教えてくれませんでした。

バージョン： のUbuntu：12.04.1 LTS のjava：1.6.0_24（OpenJDKの） のjavac：1.7.0_07（OpenJDKの）

haider@haider-desktop:~/Documents/projects/java-projects/mytestapp$ play 
[info] Loading project definition from /home/haider/Documents/projects/java-projects/mytestapp/project 
[info] Set current project to mytestapp (in build file:/home/haider/Documents/projects/java-projects/mytestapp/) 
     _   _ 
_ __ | | __ _ _ _| | 
| '_ \| |/ _' | || |_| 
| __/|_|\____|\__ (_) 
|_|   |__/ 

play! 2.0.4, http://www.playframework.org 

> Type "help play" or "license" for more information. 
> Type "exit" or use Ctrl+D to leave this console. 

[mytestapp] $ run 

--- (Running the application from SBT, auto-reloading is enabled) --- 
[info] play - Listening for HTTP on port 9000... 

(Server started, use Ctrl+D to stop and go back to the console...) 

[info] Compiling 5 Scala sources and 2 Java sources to /home/haider/Documents/projects/libraries/play-2.0.4/samples/java/helloworld/target/scala-2.9.1/classes... 
[warn] Problem processing dependencies of source /home/haider/Documents/projects/libraries/play-2.0.4/samples/java/helloworld/target/scala-2.9.1/src_managed/main/controllers/routes.java : java.lang.UnsupportedClassVersionError: controllers/routes : Unsupported major.minor version 51.0 
[warn] Problem processing dependencies of source /home/haider/Documents/projects/libraries/play-2.0.4/samples/java/helloworld/target/scala-2.9.1/src_managed/main/controllers/routes.java : java.lang.UnsupportedClassVersionError: controllers/routes$javascript : Unsupported major.minor version 51.0 
[warn] Problem processing dependencies of source /home/haider/Documents/projects/libraries/play-2.0.4/samples/java/helloworld/target/scala-2.9.1/src_managed/main/controllers/routes.java : java.lang.UnsupportedClassVersionError: controllers/routes : Unsupported major.minor version 51.0 
[warn] Problem processing dependencies of source /home/haider/Documents/projects/libraries/play-2.0.4/samples/java/helloworld/target/scala-2.9.1/src_managed/main/controllers/routes.java : java.lang.UnsupportedClassVersionError: controllers/routes$ref : Unsupported major.minor version 51.0 
[warn] Problem processing dependencies of source /home/haider/Documents/projects/libraries/play-2.0.4/samples/java/helloworld/target/scala-2.9.1/src_managed/main/controllers/routes.java : java.lang.UnsupportedClassVersionError: controllers/routes$javascript : Unsupported major.minor version 51.0 
[warn] Problem processing dependencies of source /home/haider/Documents/projects/libraries/play-2.0.4/samples/java/helloworld/target/scala-2.9.1/src_managed/main/controllers/routes.java : java.lang.UnsupportedClassVersionError: controllers/routes : Unsupported major.minor version 51.0 
[warn] Problem processing dependencies of source /home/haider/Documents/projects/libraries/play-2.0.4/samples/java/helloworld/target/scala-2.9.1/src_managed/main/controllers/routes.java : java.lang.UnsupportedClassVersionError: controllers/routes$ref : Unsupported major.minor version 51.0 
[warn] Error reading API from class file : java.lang.UnsupportedClassVersionError: controllers/routes$javascript : Unsupported major.minor version 51.0 
[warn] Error reading API from class file : java.lang.UnsupportedClassVersionError: controllers/routes : Unsupported major.minor version 51.0 
[warn] Error reading API from class file : java.lang.UnsupportedClassVersionError: controllers/routes$ref : Unsupported major.minor version 51.0 
[warn] Problem processing dependencies of source /home/haider/Documents/projects/libraries/play-2.0.4/samples/java/helloworld/app/controllers/Application.java : java.lang.UnsupportedClassVersionError: controllers/Application$Hello : Unsupported major.minor version 51.0 
[warn] Problem processing dependencies of source /home/haider/Documents/projects/libraries/play-2.0.4/samples/java/helloworld/app/controllers/Application.java : java.lang.UnsupportedClassVersionError: controllers/Application : Unsupported major.minor version 51.0 
[warn] Problem processing dependencies of source /home/haider/Documents/projects/libraries/play-2.0.4/samples/java/helloworld/app/controllers/Application.java : java.lang.UnsupportedClassVersionError: controllers/Application$Hello : Unsupported major.minor version 51.0 
[warn] Problem processing dependencies of source /home/haider/Documents/projects/libraries/play-2.0.4/samples/java/helloworld/app/controllers/Application.java : java.lang.UnsupportedClassVersionError: controllers/Application : Unsupported major.minor version 51.0 
[warn] Error reading API from class file : java.lang.UnsupportedClassVersionError: controllers/Application$Hello : Unsupported major.minor version 51.0 
[warn] Error reading API from class file : java.lang.UnsupportedClassVersionError: controllers/Application : Unsupported major.minor version 51.0 
[info] play - Application started (Dev) 

Answer 1

あなたがアプリケーションをコンパイルして実行するために、異なるJDKのバージョンを使用しています。

java: 1.6.0_24 (OpenJDK) 
javac: 1.7.0_07 (OpenJDK) 

は、だからあなたのコンパイラ（javacの）は、第2は、あなたのコンパイルされたファイルを実行することはできません意味のjavaコマンド、より新しいリリースである：あなたがいることを言います。あなたが呼び出す必要がコンパイルおよび実行の両方のためのJavaのバージョンを変更するにはUbuntuの上（のjavaとjavacのために同じ）JDKの唯一の1バージョン

Answer 2

を使用する必要があります。

sudo update-alternatives --config javac 

と

sudo update-alternatives --config java 

Answer 3

ターゲットバージョンを変更する方がよい場合は、次のように1.7から1.6にコンパイルできます。 How can I set the javac compile version for Play Framework 2.0 to prevent "Unsupported major.minor version"?

これをビルド.scala：

val main = play.Project(appName, appVersion, appDependencies).settings(
    // Force compilation in java 1.6 
    javacOptions in Compile ++= Seq("-source", "1.6", "-target", "1.6") 
)