eclipse debugging appear Source not found. Bug

Hello everyone, I am a novice, just beginning to learn to write JAVA SE small program can be debugged before the eclipse, but today suddenly go wrong, no matter what my debug code, have appeared Source not found. Mistakes, such as Figure [img = http://hi.baidu.com/% BA% C9% E9% AA% C8% CA/album/item/76ef29130ee52a745baf5355.html # t1321108739833] [/ img]


experts who help me ah, very grateful.
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Source attachment on the map is pointing to the source code (can be a jar / zip or a directory)
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see Fig.
debug to die, but to run properly?
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  The reply on 2011-11-14 10:45:30 deleted by moderator

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set breakpoints Mody?
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http:// hi.baidu.com /% BA% C9% E9% AA% C8% CA/album/item/76ef29130ee52a745baf5355.html
Edit Source Lookup Path ... after clicking out what?
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commissioning jar in the class went to the bar?
the source file add to the mix.
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no source files?
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put the source files!
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yesterday quick off the net, I did not say clearly the problem. Set a breakpoint, press F6 will appear under the map
then click Edit source lookup path will appear under the map
feeling friends brightyq said makes sense, I feel that as long as the class jump jar will appear first figure errors.
Everyone says the "source added," but the key is I do not know. " add any source files? How to add? Add to Where? ". I was a beginner, I feel this is a very elementary question, I do not want to waste everybody's time, I have carefully read the official documentation of Debug eclipse part, and also found on Google and Baidu, but are not resolved, so have to trouble you.

Please know how to fix my friends said that under the "What should be added to the source files? How to add source files? the source file to where?" extremely grateful.
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you debug files are the files in your project, you should not have this problem.
you right click on an item, select the build path -> config build path -> Source, could see his project src directory in there? If you do not see, in the right-click on the project src directory, build path -> use as source folder, you should be able to add it to the source path.
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no source documents.

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jdk comes
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third-party libraries like to add:
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I also encountered this problem,
I quoted a third-party libraries DBCP, no source code
Every time BasicDataSource ds = new BasicDataSource (); This line can not come out to find the source code, you can not continue debugging.
I just want to debug my own code, but not the DBCP code so that should also increase the DBCP source code?
eclipse is not doing too frustrated it.