If a path contains one or more white spaces you need to surround it with double quotes. For example, let's rename the "project" folder to "my project" and see how it affects the javac.exe call relative to the file system root (C:\).
As the path specified for the -d option now contains a white space, it must be surrounded by double quotes, the same applies to the path specified as the source location.
Also note that the javac.exe call relative to the "src" folder (C:\my project\src) need not change, because renaming the "project" folder hasn't affected its path references, which still do not contain any white spaces. No double quotes needed in this case.
A final suggestion, try to avoid using any white spaces in path references where Java is concerned (this includes the installation path to the JDK), because, frankly, they're more trouble then they're worth. [ March 21, 2008: Message edited by: Jelle Klap ]
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