我已经使用Android SDK Manager更新了我的软件包，并单击帮助>检查更新和更新的已安装插件。我被提示重新启动eclipse，现在重新启动后，
我得到以下错误代码
'Building workspace' has encountered a problem.
Errors occurred during the build
Errors occurred during the build.
Error instantiating builder 'com.android.ide.eclipse.adt.ResourceManagerBuilder'.
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.ResourceManagerBuilder.
Bad version number in .class file
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.ResourceManagerBuilder.
Bad version number in .class file
Error instantiating builder 'com.android.ide.eclipse.adt.PreCompilerBuilder'.
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.PreCompilerBuilder.
Bad version number in .class file
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.PreCompilerBuilder.
Bad version number in .class file
Error instantiating builder 'com.android.ide.eclipse.adt.ApkBuilder'.
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.PostCompilerBuilder.
Bad version number in .class file
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.PostCompilerBuilder.
Bad version number in .class file
Error instantiating builder 'com.android.ide.eclipse.adt.ResourceManagerBuilder'.
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.ResourceManagerBuilder.
Bad version number in .class file
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.ResourceManagerBuilder.
Bad version number in .class file
Error instantiating builder 'com.android.ide.eclipse.adt.PreCompilerBuilder'.
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.PreCompilerBuilder.
Bad version number in .class file
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.PreCompilerBuilder.
Bad version number in .class file
Error instantiating builder 'com.android.ide.eclipse.adt.ApkBuilder'.
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.PostCompilerBuilder.
Bad version number in .class file
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.PostCompilerBuilder.
Bad version number in .class file
Error instantiating builder 'com.android.ide.eclipse.adt.ResourceManagerBuilder'.
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.ResourceManagerBuilder.
Bad version number in .class file
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.ResourceManagerBuilder.
Bad version number in .class file
Error instantiating builder 'com.android.ide.eclipse.adt.PreCompilerBuilder'.
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.PreCompilerBuilder.
Bad version number in .class file
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.PreCompilerBuilder.
Bad version number in .class file
Error instantiating builder 'com.android.ide.eclipse.adt.ApkBuilder'.
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.PostCompilerBuilder.
Bad version number in .class file
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.PostCompilerBuilder.
Bad version number in .class file
Error instantiating builder 'com.android.ide.eclipse.adt.ResourceManagerBuilder'.
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.ResourceManagerBuilder.
Bad version number in .class file
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.ResourceManagerBuilder.
Bad version number in .class file
Error instantiating builder 'com.android.ide.eclipse.adt.PreCompilerBuilder'.
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.PreCompilerBuilder.
Bad version number in .class file
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.PreCompilerBuilder.
Bad version number in .class file
Error instantiating builder 'com.android.ide.eclipse.adt.ApkBuilder'.
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.PostCompilerBuilder.
Bad version number in .class file
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.PostCompilerBuilder.
Bad version number in .class file
Error instantiating builder 'com.android.ide.eclipse.adt.ResourceManagerBuilder'.
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.ResourceManagerBuilder.
Bad version number in .class file
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.ResourceManagerBuilder.
Bad version number in .class file
Error instantiating builder 'com.android.ide.eclipse.adt.PreCompilerBuilder'.
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.PreCompilerBuilder.
Bad version number in .class file
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.PreCompilerBuilder.
Bad version number in .class file
Error instantiating builder 'com.android.ide.eclipse.adt.ApkBuilder'.
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.PostCompilerBuilder.
Bad version number in .class file
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.PostCompilerBuilder.
Bad version number in .class file
Error instantiating builder 'com.android.ide.eclipse.adt.ResourceManagerBuilder'.
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.ResourceManagerBuilder.
Bad version number in .class file
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.ResourceManagerBuilder.
Bad version number in .class file
Error instantiating builder 'com.android.ide.eclipse.adt.PreCompilerBuilder'.
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.PreCompilerBuilder.
Bad version number in .class file
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.PreCompilerBuilder.
Bad version number in .class file
Error instantiating builder 'com.android.ide.eclipse.adt.ApkBuilder'.
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.PostCompilerBuilder.
Bad version number in .class file
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.PostCompilerBuilder.
Bad version number in .class file
Error instantiating builder 'com.android.ide.eclipse.adt.ResourceManagerBuilder'.
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.ResourceManagerBuilder.
Bad version number in .class file
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.ResourceManagerBuilder.
Bad version number in .class file
Error instantiating builder 'com.android.ide.eclipse.adt.PreCompilerBuilder'.
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.PreCompilerBuilder.
Bad version number in .class file
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.PreCompilerBuilder.
Bad version number in .class file
Error instantiating builder 'com.android.ide.eclipse.adt.ApkBuilder'.
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.PostCompilerBuilder.
Bad version number in .class file
Plug-in com.android.ide.eclipse.adt was unable to load class com.android.ide.eclipse.adt.internal.build.builders.PostCompilerBuilder.
Bad version number in .class file
我也有同样的错误。我再次检查了sdk更新，安装了它们，在eclipse中，我检查了更新（帮助->检查更新）。在重新开放eclipse之后，我现在恢复了正常。希望这对有帮助
您确定有正确的依赖关系吗？您安装了哪个eclipse版本？使用哪个JRE/JDK运行eclipse？
Bad version number表示目标java版本与您使用的版本不匹配（请参阅此处）。
在我的案例中，计算机重新启动解决了所有问题，而无需重新安装ADT插件。顺便说一句，我使用的是MAC+ADT_v22
我的一个项目有错误。我只是简单地
switch工作区并解决了问题。
打开Eclipse。转到文件菜单->切换工作区->其他并创建一个新的工作区路径你可以走了。