Bug 91072 F2/Hover for external javadoc does not work
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/preferences/JavadocConfigurationBlock.java
dialog.setSorter(sorter);
			
			String init= fArchivePathField.getText();
			if (init.length() == 0) {
				init= "docs/api"; 
			}
			dialog.setInitialSelection(cp.findElement(new Path(init)));
			
			dialog.setInput(this);
			if (dialog.open() == Window.OK) {
				String name= provider.getFullPath(dialog.getFirstResult());
				return new Path(name).removeTrailingSeparator().toString();
			}
		} catch (IOException e) {
			JavaPlugin.log(e);
		} finally {
			if (zipFile != null) {
				try {
					zipFile.close();
				} catch (IOException e1) {
					
				}
			}
		}
		return null;
	}
	private String chooseArchive() {
		FileDialog dialog= new FileDialog(fShell, SWT.OPEN);
		dialog.setFilterExtensions(new String[] { FILE_IMPORT_MASK });
		dialog.setText(PreferencesMessages.JavadocConfigurationBlock_zipImportSource_title);