Bug 45062 Don't filter output folder and class files
Create a Java project with source folder src and output folder bin. The bin folder will not be shown in the Packages Explorer. Create a Java project with source folder src and output folder output/bin. The output and bin folders are shown in the Packages Explorer. Implictly filtering out bin is confusing and inconsistent. A better way to do this would be to use a name filter for bin or add "Output folder" to the list of available filters.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/PackageExplorerPart.java
/**
	 * @see IWorkbenchPart#setFocus()
	 */
	public void setFocus() {
		fViewer.getTree().setFocus();
	}
	/**
	 * Returns the current selection.
	 */
	private ISelection getSelection() {
		return fViewer.getSelection();
	}
	  
	
	
	/**
	 * Called when the context menu is about to open. Override
	 * to add your own context dependent menu contributions.
	 */
	public void menuAboutToShow(IMenuManager menu) {
		JavaPlugin.createStandardGroups(menu);
		
		fActionSet.setContext(new ActionContext(getSelection()));
		fActionSet.fillContextMenu(menu);
		fActionSet.setContext(null);
	}
	private void makeActions() {
		fActionSet= new PackageExplorerActionGroup(this);
	}