public void performPaging()

in tobago-core/src/main/java/org/apache/myfaces/tobago/internal/component/AbstractUISheet.java [477:542]
60 lines of code
19 McCabe index (conditional complexity)

  public void performPaging(final PageActionEvent pageEvent) {

    int first;

    if (LOG.isDebugEnabled()) {
      LOG.debug("action = '" + pageEvent.getAction().name() + "'");
    }

    ScrollPosition scrollPosition = getState().getScrollPosition();
    scrollPosition.setTop(0);
    switch (pageEvent.getAction()) {
      case first:
        first = 0;
        break;
      case prev:
        first = getFirst() - getRows();
        first = Math.max(first, 0);
        scrollPosition.setTop(Integer.MAX_VALUE);
        break;
      case next:
        if (hasRowCount()) {
          first = getFirst() + getRows();
          first = first > getRowCount() ? getFirstRowIndexOfLastPage() : first;
        } else {
          if (isAtEnd()) {
            first = getFirst();
          } else {
            first = getFirst() + getRows();
          }
        }
        break;
      case last:
        first = getFirstRowIndexOfLastPage();
        break;
      case toRow:
      case lazy:
        first = pageEvent.getValue() - 1;
        if (hasRowCount() && first > getFirstRowIndexOfLastPage()) {
          first = getFirstRowIndexOfLastPage();
        } else if (first < 0) {
          first = 0;
        }
        break;
      case toPage:
        final int pageIndex = pageEvent.getValue() - 1;
        first = pageIndex * getRows();
        if (hasRowCount() && first > getFirstRowIndexOfLastPage()) {
          first = getFirstRowIndexOfLastPage();
        } else if (first < 0) {
          first = 0;
        }
        break;
      default:
        // may not happen
        first = -1;
    }

    final ValueExpression expression = getValueExpression(Attributes.first.getName());
    if (expression != null) {
      expression.setValue(getFacesContext().getELContext(), first);
    } else {
      setFirst(first);
    }

    getState().setFirst(first);
  }