eclipse启动报错：An error has occurred.See the log file D:\eclipse\configuration\1552616709202.log

　　如题，Eclipse崩了，只能按它留下的线索去看了1552616709202.log：

!SESSION 2019-03-15 10:25:08.739 -----------------------------------------------
eclipse.buildId=4.6.2.M20161124-1400
java.version=1.8.0_181
java.vendor=Oracle Corporation
BootLoader constants: OS=win32, ARCH=x86_64, WS=win32, NL=zh_CN
Framework arguments:  -product org.eclipse.epp.package.jee.product
Command-line arguments:  -os win32 -ws win32 -arch x86_64 -product org.eclipse.epp.package.jee.product

!ENTRY org.eclipse.equinox.ds 2 0 2019-03-15 10:25:40.333
!MESSAGE [SCR - WorkThread] Timeout occurred! Thread was blocked on processing [QueuedJob] WorkPerformer: org.eclipse.equinox.internal.ds.SCRManager@701a36b3; actionType 1

!ENTRY org.eclipse.equinox.ds 2 0 2019-03-15 10:25:40.340
!MESSAGE [SCR] Enabling components of bundle org.eclipse.ui.trace did not complete in 30000 ms 

!ENTRY org.eclipse.core.runtime 4 0 2019-03-15 10:25:45.367
!MESSAGE FrameworkEvent ERROR
!STACK 0
org.osgi.framework.BundleException: Unable to acquire the state change lock for the module: osgi.identity; type="osgi.bundle"; version:Version="3.12.0.v20160606-1342"; osgi.identity="org.eclipse.core.runtime"; singleton:="true" [id=112] STARTED [STARTED]
    at org.eclipse.osgi.container.Module.lockStateChange(Module.java:337)
    at org.eclipse.osgi.container.Module.start(Module.java:401)
    at org.eclipse.osgi.container.ModuleContainer$ContainerStartLevel.incStartLevel(ModuleContainer.java:1620)
    at org.eclipse.osgi.container.ModuleContainer$ContainerStartLevel.incStartLevel(ModuleContainer.java:1600)
    at org.eclipse.osgi.container.ModuleContainer$ContainerStartLevel.doContainerStartLevel(ModuleContainer.java:1571)
    at org.eclipse.osgi.container.ModuleContainer$ContainerStartLevel.dispatchEvent(ModuleContainer.java:1514)
    at org.eclipse.osgi.container.ModuleContainer$ContainerStartLevel.dispatchEvent(ModuleContainer.java:1)
    at org.eclipse.osgi.framework.eventmgr.EventManager.dispatchEvent(EventManager.java:230)
    at org.eclipse.osgi.framework.eventmgr.EventManager$EventThread.run(EventManager.java:340)
Caused by: java.util.concurrent.TimeoutException: Timeout after waiting 5 seconds to acquire the lock.
    at org.eclipse.osgi.container.Module.lockStateChange(Module.java:334)
    ... 8 more
Root exception:
java.util.concurrent.TimeoutException: Timeout after waiting 5 seconds to acquire the lock.
    at org.eclipse.osgi.container.Module.lockStateChange(Module.java:334)
    at org.eclipse.osgi.container.Module.start(Module.java:401)
    at org.eclipse.osgi.container.ModuleContainer$ContainerStartLevel.incStartLevel(ModuleContainer.java:1620)
    at org.eclipse.osgi.container.ModuleContainer$ContainerStartLevel.incStartLevel(ModuleContainer.java:1600)
    at org.eclipse.osgi.container.ModuleContainer$ContainerStartLevel.doContainerStartLevel(ModuleContainer.java:1571)
    at org.eclipse.osgi.container.ModuleContainer$ContainerStartLevel.dispatchEvent(ModuleContainer.java:1514)
    at org.eclipse.osgi.container.ModuleContainer$ContainerStartLevel.dispatchEvent(ModuleContainer.java:1)
    at org.eclipse.osgi.framework.eventmgr.EventManager.dispatchEvent(EventManager.java:230)
    at org.eclipse.osgi.framework.eventmgr.EventManager$EventThread.run(EventManager.java:340)

　　从日志看是拿锁超时了，关键是锁在哪？锁在工作空间的.metadata目录里：

　　把这个日志（eclipse\configuration\1552616709202.log）和锁（workspace\.metadata\.lock）删了再试试就ok了，Eclipse正常启动。

　　碰到这种启动失败的场景，基本就是清理这两个目录（configuration和.metadata）这条路子。