How to use javax.faces

@Override
public UIComponent resolveComponent(FacesContext context, UIComponent source, UIComponent last, String expression, int options) {
  throw new FacesException("jQuery selectors aka PFS are not supported on the server side... expression \"" + expression
      + "\" referenced from \"" + source.getClientId(context) + "\".");
}

private void validateIterationControlValues(int rowCount,
                      int begin,
                      int end) {
  if (rowCount == 0) {
    return;
  }
  // PENDING i18n
  if (begin > rowCount) {
    throw new FacesException("Iteration start index is greater than the number of available rows.");
  }
  if (begin > end) {
    throw new FacesException("Iteration start index is greater than the end index.");
  }
  if (end > rowCount) {
    throw new FacesException("Iteration end index is greater than the number of available rows.");
  }
}

  protected List resolveList(Object value) {
    if (value instanceof List) {
      return (List) value;
    }
    else if (value instanceof ListDataModel) {
      return (List) ((ListDataModel) value).getWrappedData();
    }
    else {
      throw new FacesException("Data type should be java.util.List or javax.faces.model.ListDataModel instance to be sortable.");
    }
  }
}

public static <T extends Renderer> T getUnwrappedRenderer(FacesContext context, String family, String rendererType, Class<T> rendererClass) {
  Renderer renderer = context.getRenderKit().getRenderer(family, rendererType);
  while (renderer instanceof FacesWrapper) {
    renderer = (Renderer) ((FacesWrapper) renderer).getWrapped();
  }
  return (T) renderer;
}

 @Named
@RequestScoped // Or @ViewScoped
public class Bean {

  private Future<List<Entity>> asyncEntities;

  @EJB
  private EntityService entityService;

  @PostConstruct
  public void init() {
    asyncEntities = entityService.asyncList();
    // ... (this code will immediately continue without waiting)
  }

  public List<Entity> getEntities() {
    try {
      return asyncEntities.get();
    } catch (InterruptedException e) {
      Thread.currentThread().interrupt();
      throw new FacesException(e);
    } catch (ExecutionException e) {
      throw new FacesException(e);
    }
  }
}

@Override
public UIComponent resolveComponent(FacesContext context, UIComponent source, UIComponent last, String expression, int options) {
  throw new FacesException("@row likely returns multiple components, therefore it's not supported in #resolveComponent... expression \""
      + expression + "\" referenced from \"" + source.getClientId(context) + "\".");
}

public void postConstruct(Object obj) throws IllegalAccessException, InvocationTargetException {
  // WFLY-3387 MyFaces injects managed properties before calling this method
  try {
    injectionContainer.newInstance(obj);
  } catch (NamingException e) {
    throw new FacesException(e);
  }
}

  protected String extractId(String expression) {
    try {
      Matcher matcher = PATTERN.matcher(expression);

      if (matcher.matches()) {

        return matcher.group(1);

      }
      else {
        throw new FacesException("Expression does not match following pattern @id(id). Expression: \"" + expression + "\"");
      }

    }
    catch (Exception e) {
      throw new FacesException("Expression does not match following pattern @id(id). Expression: \"" + expression + "\"", e);
    }
  }
}

  private String decode(String encoded) {
    try {
      // GitHub #3916 escape + and % before decode
      encoded = encoded.replaceAll("%(?![0-9a-fA-F]{2})", "%25");
      encoded = encoded.replaceAll("\\+", "%2B");
      return URLDecoder.decode(encoded, "UTF-8");
    }
    catch (UnsupportedEncodingException ex) {
      throw new FacesException(ex);
    }
  }
}

  protected UIData findDatasource(FacesContext context, Droppable droppable, String datasourceId) {
    UIComponent datasource = SearchExpressionFacade.resolveComponent(context, droppable, datasourceId);

    if (datasource == null) {
      throw new FacesException("Cannot find component \"" + datasourceId + "\" in view.");
    }
    else {
      return (UIData) datasource;
    }
  }
}

public static byte[] toByteArray(InputStream stream) {
  try {
    ByteArrayOutputStream buffer = new ByteArrayOutputStream();
    int nRead;
    byte[] data = new byte[16384];
    while ((nRead = stream.read(data, 0, data.length)) != -1) {
      buffer.write(data, 0, nRead);
    }
    buffer.flush();
    return buffer.toByteArray();
  }
  catch (Exception e) {
    throw new FacesException("Could not read InputStream to byte[]", e);
  }
}

  public FilterConstraint getFilterConstraint(UIColumn column) {
    String filterMatchMode = column.getFilterMatchMode();
    FilterConstraint filterConstraint = TreeTable.FILTER_CONSTRAINTS.get(filterMatchMode);

    if (filterConstraint == null) {
      throw new FacesException("Illegal filter match mode:" + filterMatchMode);
    }

    return filterConstraint;
  }
}

  public FilterConstraint getFilterConstraint(Tree tree) {
    String filterMatchMode = tree.getFilterMatchMode();
    FilterConstraint filterConstraint = Tree.FILTER_CONSTRAINTS.get(filterMatchMode);

    if (filterConstraint == null) {
      throw new FacesException("Illegal filter match mode:" + filterMatchMode);
    }

    return filterConstraint;
  }
}

public FilterConstraint getFilterConstraint(UIColumn column) {
  String filterMatchMode = column.getFilterMatchMode();
  FilterConstraint filterConstraint = FILTER_CONSTRAINTS.get(filterMatchMode);
  if (filterConstraint == null) {
    throw new FacesException("Illegal filter match mode:" + filterMatchMode);
  }
  return filterConstraint;
}

public UITreeNode getUITreeNodeByType(String type) {
  UITreeNode node = getTreeNodes().get(type);
  if (node == null) {
    throw new javax.faces.FacesException("Unsupported tree node type:" + type);
  }
  else {
    return node;
  }
}

/**
 * Creates an RFC 6266 Content-Dispostion header following all UTF-8 conventions.
 * <p>
 * @param value e.g. "attachment"
 * @param filename the name of the file
 * @return a valid Content-Disposition header in UTF-8 format
 */
public static String createContentDisposition(String value, String filename) {
  try {
    return String.format("%s;filename=\"%2$s\"; filename*=UTF-8''%2$s", value, encodeURI(filename));
  }
  catch (UnsupportedEncodingException e) {
    throw new FacesException(e);
  }
}

  @Override
  public V get(Object key) {
    if (!containsKey(key)) {
      throw new FacesException("Class " + clazz.getName() + " does not contain the enum " + key);
    }

    return super.get(key);
  }
}

protected SelectItem[] getFilterOptions(UIColumn column) {
  Object options = column.getFilterOptions();
  if (options instanceof SelectItem[]) {
    return (SelectItem[]) options;
  }
  else if (options instanceof Collection<?>) {
    return ((Collection<SelectItem>) column.getFilterOptions()).toArray(new SelectItem[]{});
  }
  else {
    throw new FacesException("Filter options for column " + column.getClientId() + " should be a SelectItem array or collection");
  }
}

@Override
public void encodeEnd(FacesContext context, UIComponent component) throws IOException {
  Captcha captcha = (Captcha) component;
  String publicKey = getPublicKey(context, captcha);
  if (publicKey == null) {
    throw new FacesException("Cannot find public key for catpcha, use primefaces.PUBLIC_CAPTCHA_KEY context-param to define one");
  }
  encodeMarkup(context, captcha, publicKey);
  encodeScript(context, captcha, publicKey);
}

public Object getRowKeyFromModel(Object object) {
  DataModel model = getDataModel();
  if (!(model instanceof SelectableDataModel)) {
    throw new FacesException("DataModel must implement org.primefaces.model.SelectableDataModel when selection is enabled.");
  }
  return ((SelectableDataModel) getDataModel()).getRowKey(object);
}