radrails无法启动

周一上班，刚想开始工作，却发现 radrails 无法启动了。workspace 的 log 文件给出了下列的错误信息。

引用

!SESSION 2007-09-03 15:51:34.795 -----------------------------------------------
eclipse.buildId=unknown
java.version=1.5.0_10
java.vendor=Sun Microsystems Inc.
BootLoader constants: OS=win32, ARCH=x86, WS=win32, NL=ja_JP
Command-line arguments: -os win32 -ws win32 -arch x86 -clean

This is a continuation of log file C:\ruby\Rails\.metadata\.bak_0.log
Created Time: 2007-09-03 15:51:44.220

    !ENTRY org.eclipse.osgi 4 0 2007-09-03 15:51:44.220
    !MESSAGE Application error
    !STACK 1
    java.lang.NoClassDefFoundError: org/eclipse/core/resources/IProject
    at org.eclipse.ui.internal.ide.model.WorkbenchAdapterFactory.(WorkbenchAdapterFactory.java:35)
    at org.eclipse.ui.internal.ide.model.WorkbenchAdapterBuilder.registerAdapters(WorkbenchAdapterBuilder.java:33)
    at org.radrails.ide.ui.RadRailsWorkbenchAdvisor.preStartup(RadRailsWorkbenchAdvisor.java:56)
    at org.eclipse.ui.internal.Workbench.init(Workbench.java:1083)
    at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:1847)
    at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:419)
    at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)
    at org.radrails.ide.ui.RadRails.run(RadRails.java:78)
    at org.eclipse.core.internal.runtime.PlatformActivator$1.run(PlatformActivator.java:78)
    at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:92)
    at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:68)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:400)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:177)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at org.eclipse.core.launcher.Main.invokeFramework(Main.java:336)
    at org.eclipse.core.launcher.Main.basicRun(Main.java:280)
    at org.eclipse.core.launcher.Main.run(Main.java:977)
    at org.eclipse.core.launcher.Main.main(Main.java:952)

在网上调查了一下，radrails 采用的是 eclipse 的框架，是 eclipse 的问题。workspace    的设置文件出了问题。具体原因不明。把 C:\workspace\.metadata\.plugins\org.eclipse.core.resources\.snap 删除了后，问题解决。

突然想到，是不是对代码进行修改后没有关闭文件，之后又用 subversion 切换了工作的 branch，而引发的问题呢。