package org.argeo.eclipse.ui.specific;
   
   import java.util.Locale;
   
   import javax.servlet.http.HttpServletRequest;
   import javax.servlet.http.HttpServletResponse;
   
   import org.eclipse.rap.rwt.RWT;
   import org.eclipse.swt.widgets.Display;
  
  /** Singleton class providing single sources infos about the UI context. */
  public class UiContext {
  	/** Can be null, thus indicating that we are not in a web context. */
  	public static HttpServletRequest getHttpRequest() {
  		return RWT.getRequest();
  	}
  
  	public static HttpServletResponse getHttpResponse() {
  		return RWT.getResponse();
  	}
  
  	public static Locale getLocale() {
  		if (Display.getCurrent() != null)
  			return RWT.getUISession().getLocale();
  		else
  			return Locale.getDefault();
  	}
  
  	public static void setLocale(Locale locale) {
  		if (Display.getCurrent() != null)
  			RWT.getUISession().setLocale(locale);
  		else
  			Locale.setDefault(locale);
  	}
  
  	/** Can always be null */
  	@SuppressWarnings("unchecked")
  	public static <T> T getData(String key) {
  		Display display = getDisplay();
  		if (display == null)
  			return null;
  		return (T) display.getData(key);
  	}
  
  	public static void setData(String key, Object value) {
  		Display display = getDisplay();
  		if (display == null)
  			throw new SingleSourcingException("Not display available in RAP context");
  		display.setData(key, value);
  	}
  
  	private static Display getDisplay() {
  		return Display.getCurrent();
  	}
  
  	private UiContext() {
  	}
  
  }