java.lang.UnsupportedClassVersionError:com/google/appengine/tools/development/agent/AppEngineDevAgent:不支持的major.minor版本51.0

Question

当我试图运行一个gwt项目时,它得到了以下错误

java.lang.UnsupportedClassVersionError: com/google/appengine/tools/development/agent/AppEngineDevAgent : Unsupported major.minor version 51.0
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:621)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:260)
at java.net.URLClassLoader.access$000(URLClassLoader.java:56)
at java.net.URLClassLoader$1.run(URLClassLoader.java:195)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
at java.lang.ClassLoader.loadClass(ClassLoader.java:252)
at sun.instrument.InstrumentationImpl.loadClassAndStartAgent(InstrumentationImpl.java:280)
at sun.instrument.InstrumentationImpl.loadClassAndCallPremain(InstrumentationImpl.java:338)

本机方法中的致命错误:-javaagent处理失败线程"main"中的异常

我的JRE系统库是jre6,我在编译器合规级别选择1.6,但它仍然相同,所以我该怎么办？

Answer 1

AppEngine需要Java 7,最新版本使用Java 7 compliance(-target 1.7)进行编译,因此无法在Java 6 VM中加载这些类.这实际上是异常告诉你的.