Question

我正在使用Eclipse 4.4.1和最新的gae插件。当我在项目中保存da java文件时，抛出了一个NPE：“构建期间发生错误。错误在项目上运行构建器'Enhancer'。”

这是堆栈跟踪：

!STACK 0
!MESSAGE Problems occurred when invoking code from plug-in: "org.eclipse.core.resources".
java.lang.NullPointerException
    at com.google.appengine.eclipse.core.orm.enhancement.AutoEnhancer.hasValidSdk(AutoEnhancer.java:188)
    at com.google.appengine.eclipse.core.orm.enhancement.AutoEnhancer.build(AutoEnhancer.java:126)
    at org.eclipse.core.internal.events.BuildManager$2.run(BuildManager.java:734)
    at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
    at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:206)
    at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:246)
    at org.eclipse.core.internal.events.BuildManager$1.run(BuildManager.java:299)
    at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
    at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:302)
    at org.eclipse.core.internal.events.BuildManager.basicBuildLoop(BuildManager.java:358)
    at org.eclipse.core.internal.events.BuildManager.build(BuildManager.java:381)
    at org.eclipse.core.internal.events.AutoBuildJob.doBuild(AutoBuildJob.java:143)
    at org.eclipse.core.internal.events.AutoBuildJob.run(AutoBuildJob.java:241)
    at org.eclipse.core.internal.jobs.Worker.run(Worker.java:54)

!MESSAGE Errors running builder 'Enhancer' on project ...
!STACK 0
java.lang.NullPointerException
    at com.google.appengine.eclipse.core.orm.enhancement.AutoEnhancer.hasValidSdk(AutoEnhancer.java:188)
    at com.google.appengine.eclipse.core.orm.enhancement.AutoEnhancer.build(AutoEnhancer.java:126)
    at org.eclipse.core.internal.events.BuildManager$2.run(BuildManager.java:734)
    at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
    at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:206)
    at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:246)
    at org.eclipse.core.internal.events.BuildManager$1.run(BuildManager.java:299)
    at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
    at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:302)
    at org.eclipse.core.internal.events.BuildManager.basicBuildLoop(BuildManager.java:358)
    at org.eclipse.core.internal.events.BuildManager.build(BuildManager.java:381)
    at org.eclipse.core.internal.events.AutoBuildJob.doBuild(AutoBuildJob.java:143)
    at org.eclipse.core.internal.events.AutoBuildJob.run(AutoBuildJob.java:241)
    at org.eclipse.core.internal.jobs.Worker.run(Worker.java:54)

Answer 1

正在发生的事情是在非WST或WTP项目与WTP配置之间切换，这意味着经典的GWT / GAE发射器会受到WTP系统的破坏。

当配置切换到新配置时，有一个设置没有关闭。

解决方法修复。

可选：关闭所有不相关的项目 - 这有助于钻孔。
删除.settings目录 - 清除设置
运行Maven更新 - 重建eclipse的.settings

这很快就会修复。

关于项目更新的Eclipse NPE

1 个答案: