001/* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017package org.apache.wicket.extensions.markup.html.repeater.data.table; 018 019import org.apache.wicket.Component; 020import org.apache.wicket.extensions.markup.html.repeater.data.grid.ICellPopulator; 021 022 023/** 024 * An interface that represents a column in the {@link DefaultDataTable} 025 * 026 * @author Igor Vaynberg ( ivaynberg ) 027 * @param <T> 028 * the type of the object that will be rendered in this column's cells 029 * @param <S> 030 * the type of the sorting parameter 031 */ 032public interface IColumn<T, S> extends ICellPopulator<T> 033{ 034 /** 035 * Returns the component that will be used as the header for the column. 036 * 037 * This component will be contained in <span> tags. 038 * 039 * @param componentId 040 * component id for the returned Component 041 * 042 * @return component that will be used as the header for the column 043 */ 044 Component getHeader(String componentId); 045 046 /** 047 * Returns the property that this header sorts on. 048 * If {@code null} is returned the header will be not sortable. 049 * 050 * @return the sort property 051 */ 052 S getSortProperty(); 053 054 /** 055 * Returns true if the header of the column should be sortable 056 * 057 * @return true if header should be sortable 058 */ 059 default boolean isSortable() 060 { 061 return getSortProperty() != null; 062 } 063 064 /** 065 * @return The number of rows the header of this column should span 066 */ 067 default int getHeaderRowspan() { 068 return 1; 069 } 070 071 /** 072 * @return The number of columns the header of this column should span 073 */ 074 default int getHeaderColspan() { 075 return 1; 076 } 077}