import javax.swing.*; import java.awt.*; public class Bar { static class CellWrapper { public boolean isSeparator() { return true; } } static class MyRenderer extends DefaultListCellRenderer { public Component getListCellRendererComponent(JList list, Object value, int index, boolean s, boolean focus) { assert value instanceof CellWrapper; ((CellWrapper) value).isSeparator()<caret> mySelected = isSelected; } } }