Find a lot of articles on the Internet, summed up as follows:
MyEclipse does not compile the resolution 1. Make sure the project->build automatically has been selected.
MyEclipse does not compile the resolution 2. If selected, also does not work, use this trick: Project->clean. -> Select 2nd Clean Select project, hook up start build immediatelly
MyEclipse does not compile the resolution 3. Delete the current project, set up the output path of the compiled file in advance, re-import the source file, set the MyEclipse to compile when saving, and then compile it automatically when you save it.
MyEclipse does not compile the solution 4. If the project leads to a unused jar pack, and that bag was deleted by you, there will be no error but how can not compile the class file situation, you can remove all the packages, and then one after the introduction (need), not all of a sudden put all the packages are introduced, The useless may cause the bad result.
MyEclipse does not compile the resolution 5. You want to delete a class file to regenerate, remove the class file, but the folder under the Classes directory is opened by other programs, such as Total commander. At this point, the compilation will not pass, under problems may prompt "con" t delete classes ... ". Turn off other programs and recompile.
MyEclipse does not compile the solution 6. There is a situation where the JRE System Library is removed and can be compiled by re-import. But what causes it is not clear.
MyEclipse not compile resolution 7. Remove all the packages from the build path. Then add Jars,add libraries the need to add in, incredibly began to compile ...
MyEclipse do not compile to resolve 8.project->properties->java build PATH->SOURCE->.../WEB-INF/SRC output folder do not default, Edit let it point to.. /web-inf/classes
Then click the Build project again to automatically compile. My problem is here, I accidentally deleted this compilation directory
MyEclipse does not compile the solution 9. Then the most important to see whether the project below the lack of work directory, because the CVS control does not add work version, so checkout after the directory, to hand-add some of the project can be automatically compiled
In the beginning, I only found the first 7 methods, but they did not solve my problem. Accidentally I opened the "Problems" tag, found inside said missing work directory, manually plus, and then refresh the project on it.
The last two were found when I wrote this summary. In particular, the Nineth article is useful for projects that use CVS for versioning.
. classpath this XML file should be looked at carefully