code: private void doGet() throws PageException {
  	// "HKEY_LOCAL_MACHINE\\SOFTWARE\\Google\\NavClient","installtime"
  	if (entry == null) throw new ApplicationException("attribute entry is required for tag registry, when action is [get]");
  	if (variable == null) throw new ApplicationException("attribute variable is required for tag registry, when action is [get]");
  	// if(type==-1)throw new ApplicationException("attribute type is required for tag registry, when
  	// action is [get]");
  
  	try {
  	    RegistryEntry re = RegistryQuery.getValue(branch, entry, type);
  	    if (re != null) pageContext.setVariable(variable, re.getValue());
  	}
  	catch (Exception e) {
  	    throw Caster.toPageException(e);
  	}
  
      }
docs: @throws PageException