Bug 37197 Basepath for relative pathes in JAR-exporter
The basepath for the JAR-exporter is the eclipse-install-directory. I prefer it to be the root of the project (the description is saved in), so that relative pathes end inside the project. Now: <jardesc> <jar path="workspace/projectdir/jar.jar"/> Desired: <jardesc> <jar path="jar.jar"/> Reason: To make the jardesc-files portable for shared projects
org.eclipse.jdt.ui/ui/org/eclipse/jdt/ui/jarpackager/JarWriter.java
contentStream.close();
			} catch (IOException ex) {
				throw JarPackagerUtil.createCoreException(ex.getLocalizedMessage(), ex);
			}
		}
		try {
			IPath fileLocation= resource.getLocation();
			long lastModified= System.currentTimeMillis();
			if (fileLocation != null) {
				File file= new File(fileLocation.toOSString());
				if (file.exists())
					lastModified= file.lastModified();
			}
			write(destinationPath, output.toByteArray(), lastModified);
		} catch (IOException ex) {
			
			String message= null;
			if (ex.getLocalizedMessage() != null)
				message= JarPackagerMessages.getFormattedString("JarWriter.writeProblemWithMessage", resource.getFullPath(), ex.getLocalizedMessage()); 
			else
				message= JarPackagerMessages.getFormattedString("JarWriter.writeProblem", resource.getFullPath()); 
			throw JarPackagerUtil.createCoreException(message, ex);
		}					
	}
	
	/**
	 * Creates a new JarEntry with the passed path and contents, and writes it
	 * to the current archive.
	 *
	 * @param	path			the path inside the archive