eclipse又报错了,求各位快来看看,看看有什么解决方法

eclipse又报错了,求各位大虾快来看看,看看有什么解决办法
昨天还是好好的,今天一打开,代码就一大堆错误,基本上都是提示 ....cannot be resolved to a type,但是很奇怪,我把java文件关掉,重新再打开,错误又没了,一开始是弹出一个错误框,Android SDK: Resolving error markers

网上的说法是这样的:
// In some cases, the workspace may be locked for modification when we 
// pass here. 
// We schedule a new job to put the marker after. 


So make sure your workspace is not locked for modification (i.e., it's 
writable on disk). Why they don't put this in the error itself is beyond me. 
我把项目重新导了一遍,错误提示框没了,但是代码还是一大堆红叉叉,还是关掉再打开就没红叉叉,

我看了一下log文件,是这样的:
!SESSION 2011-09-09 08:49:47.376 -----------------------------------------------
eclipse.buildId=
java.version=1.6.0_10-rc2
java.vendor=Sun Microsystems Inc.
BootLoader constants: OS=win32, ARCH=x86, WS=win32, NL=en_US
Framework arguments: -product org.eclipse.epp.package.jee.product
Command-line arguments: -os win32 -ws win32 -arch x86 -product org.eclipse.epp.package.jee.product

!ENTRY org.eclipse.core.resources 2 10035 2011-09-09 08:49:49.373
!MESSAGE The workspace exited with unsaved changes in the previous session; refreshing workspace to recover changes.
求解释啊,大虾快来看看,网上的办法我都是过了……………………


------解决方案--------------------
哎,有得时候就是eclispe犯毛病,你把工程clean下就好了。嘿嘿eclispe也不是很完善。遇到过很多次,没办法,免费得东西都是有缺陷的