Bug 31556 Export jar from Navigator view fails
(M5 build) In Navigator view (resource perspective), right-click on a src/ directory containing your sources, select export->jar file and the package selector opens with no resource selected (and finish button disabled); but it seems that the src/ dir is really selected, because if you re-select it in the window, it ends up with a "jar creation failed" and a lot of duplicate entries in the error log. If you try the same from the Projects view (Java browsing perspective), it works fine.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/jarpackager/JarPackageWizardPage.java
fCompressCheckbox.setSelection(fJarPackage.isCompressed());
		fOverwriteCheckbox.setSelection(fJarPackage.allowOverwrite());
	}
	/**
	 *	Initializes the JAR package from last used wizard page values.
	 */
	protected void initializeJarPackage() {
		IDialogSettings settings= getDialogSettings();
		if (settings != null) {
			
			fJarPackage.setElements(getSelectedElements());
			fJarPackage.setExportClassFiles(settings.getBoolean(STORE_EXPORT_CLASS_FILES));
			fJarPackage.setExportJavaFiles(settings.getBoolean(STORE_EXPORT_JAVA_FILES));
			
			fJarPackage.setCompress(settings.getBoolean(STORE_COMPRESS));
			fJarPackage.setOverwrite(settings.getBoolean(STORE_OVERWRITE));
						
			
			String[] directoryNames= settings.getArray(STORE_DESTINATION_NAMES);
			if (directoryNames == null)
				return; 
			fJarPackage.setJarLocation(new Path(directoryNames[0]));
		}
	}
	/**
	 *	Stores the widget values in the JAR package.
	 */
	protected void updateModel() {