Bug 166972 [Workbench] Migrate org.eclipse.ui.ide.workbench to IApplication
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/ide/IDEApplication.java
File.separatorChar, '/');
                url = new URL("file", null, path); 
            } catch (MalformedURLException e) {
                MessageDialog
                        .openError(
                                shell,
                                IDEWorkbenchMessages.IDEApplication_workspaceInvalidTitle,
                                IDEWorkbenchMessages.IDEApplication_workspaceInvalidMessage);
                continue;
            }
        } while (!checkValidWorkspace(shell, url));
        return url;
    }
    /**
     * Return true if the argument directory is ok to use as a workspace and
     * false otherwise. A version check will be performed, and a confirmation
     * box may be displayed on the argument shell if an older version is
     * detected.
     * 
     * @return true if the argument URL is ok to use as a workspace and false
     *         otherwise.
     */
    private boolean checkValidWorkspace(Shell shell, URL url) {
        
        if (url == null) {
			return false;
		}
        String version = readWorkspaceVersion(url);