解决Eclipse启动报缺少javax/annotation/PostConstruct的错误

• 版权声明：本文为博主chszs的原创文章，未经博主允许不得转载。

我使用的是Mac开发环境，Eclipse使用4.7的Oxygen版。
当我在本机上安装了Java 9后，我发现Eclipse无法启动了。
打开Eclipse的日志文件（我的在这里Users/XXXXX/Documents/eclipsework/.metadata/.log）

可以看到有如下错误输出：

!SESSION 2017-10-08 22:04:45.234 -----------------------------------------------
eclipse.buildId=4.7.0.I20170612-0950
java.version=9
java.vendor=Oracle Corporation
BootLoader constants: OS=macosx, ARCH=x86_64, WS=cocoa, NL=zh_CN
Framework arguments:  -product org.eclipse.epp.package.jee.product -keyring /Users/liqiang/.eclipse_keyring
Command-line arguments:  -os macosx -ws cocoa -arch x86_64 -product org.eclipse.epp.package.jee.product -keyring /Users/liqiang/.eclipse_keyring

!ENTRY org.eclipse.osgi 4 0 2017-10-08 22:04:47.669
!MESSAGE Application error
!STACK 1
org.eclipse.e4.core.di.InjectionException: java.lang.NoClassDefFoundError: javax/annotation/PostConstruct
    at org.eclipse.e4.core.internal.di.InjectorImpl.internalMake(InjectorImpl.java:410)
    at org.eclipse.e4.core.internal.di.InjectorImpl.make(InjectorImpl.java:318)
    at org.eclipse.e4.core.contexts.ContextInjectionFactory.make(ContextInjectionFactory.java:162)
    at org.eclipse.e4.ui.internal.workbench.swt.E4Application.createDefaultHeadlessContext(E4Application.java:491)
    at org.eclipse.e4.ui.internal.workbench.swt.E4Application.createDefaultContext(E4Application.java:505)
    at org.eclipse.e4.ui.internal.workbench.swt.E4Application.createE4Workbench(E4Application.java:204)
    at org.eclipse.ui.internal.Workbench.lambda$3(Workbench.java:614)
    at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:336)
    at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:594)
    at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:148)
    at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:151)
    at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
    at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:134)
    at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:104)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:388)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:243)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:564)
    at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:653)
    at org.eclipse.equinox.launcher.Main.basicRun(Main.java:590)
    at org.eclipse.equinox.launcher.Main.run(Main.java:1499)
Caused by: java.lang.NoClassDefFoundError: javax/annotation/PostConstruct
    at org.eclipse.e4.core.internal.di.InjectorImpl.inject(InjectorImpl.java:124)
    at org.eclipse.e4.core.internal.di.InjectorImpl.internalMake(InjectorImpl.java:399)
    ... 22 more
Caused by: java.lang.ClassNotFoundException: javax.annotation.PostConstruct cannot be found by org.eclipse.e4.core.di_1.6.100.v20170421-1418
    at org.eclipse.osgi.internal.loader.BundleLoader.findClassInternal(BundleLoader.java:433)
    at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:395)
    at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:387)
    at org.eclipse.osgi.internal.loader.ModuleClassLoader.loadClass(ModuleClassLoader.java:150)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:496)
    ... 24 more

这个错误是安装了Java 9环境后导致的，即使卸载了Java 9，回退到Java 8，仍然有这个问题。

要解决这个问题并不难，打开Finder，选择“应用程序”，找到Eclipse，鼠标右键点击图标，选择“显示包内容”，打开“Contents”–>“Eclipse”，找到文件“eclipse.ini”
编辑这个文件，在末尾加上一句：

--add-modules=ALL-SYSTEM

保存，并退出Finder，重启Eclipse即可恢复正常。