001 // Copyright 2004, 2005 The Apache Software Foundation 002 // 003 // Licensed under the Apache License, Version 2.0 (the "License"); 004 // you may not use this file except in compliance with the License. 005 // You may obtain a copy of the License at 006 // 007 // http://www.apache.org/licenses/LICENSE-2.0 008 // 009 // Unless required by applicable law or agreed to in writing, software 010 // distributed under the License is distributed on an "AS IS" BASIS, 011 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 012 // See the License for the specific language governing permissions and 013 // limitations under the License. 014 015 package org.apache.tapestry.components; 016 017 import org.apache.tapestry.IComponent; 018 import org.apache.tapestry.IMarkupWriter; 019 import org.apache.tapestry.IRequestCycle; 020 import org.apache.tapestry.engine.ILink; 021 022 /** 023 * A component that renders an HTML <a> element. It exposes some 024 * properties to the components it wraps. This is basically to facilitate the 025 * {@link org.apache.tapestry.html.Rollover} component. 026 * 027 * @author Howard Lewis Ship 028 */ 029 030 public interface ILinkComponent extends IComponent 031 { 032 033 /** 034 * Returns the desired scheme (i.e., "http" or "https") for the link, or 035 * null to not output a specific scheme (in which case the URL will fall 036 * under the incoming request's scheme). 037 * 038 * @since 4.0 039 */ 040 041 String getScheme(); 042 043 /** 044 * Returns the desired port (i.e., "80" or "443") for the link, or null to 045 * not output a specific port (in which case the URL will fall under the 046 * incoming request's port). 047 * 048 * @since 4.1 049 */ 050 051 Integer getPort(); 052 053 /** 054 * Returns whether this service link component is enabled or disabled. 055 * 056 * @since 0.2.9 057 */ 058 059 boolean isDisabled(); 060 061 /** 062 * Returns the anchor defined for this link, or null for no anchor. 063 * 064 * @since 3.0 065 */ 066 067 String getAnchor(); 068 069 /** 070 * Returns the name of the target window or frame for this link, or null if 071 * current window or frame is to be used. 072 * 073 * @since 4.0 074 */ 075 String getTarget(); 076 077 /** 078 * Adds a new event handler. When the event occurs, the JavaScript function 079 * specified is executed. Multiple functions can be specified, in which case 080 * all of them are executed. 081 * <p> 082 * This was created for use by {@link org.apache.tapestry.html.Rollover} to 083 * set mouse over and mouse out handlers on the {@link ILinkComponent} that 084 * wraps it, but can be used for many other things as well. 085 * 086 * @since 0.2.9 087 */ 088 089 void addEventHandler(LinkEventType type, String functionName); 090 091 /** 092 * Invoked by the {@link org.apache.tapestry.link.ILinkRenderer} (if the 093 * link is not disabled) to provide a 094 * {@link org.apache.tapestry.engine.EngineServiceLink} that the renderer 095 * can convert into a URL. 096 */ 097 098 ILink getLink(IRequestCycle cycle); 099 100 /** 101 * Invoked (by the {@link org.apache.tapestry.link.ILinkRenderer}) to make 102 * the link render any additional attributes. These are informal parameters, 103 * plus any attributes related to events. This is only invoked for 104 * non-disabled links. 105 * 106 * @since 3.0 107 */ 108 109 void renderAdditionalAttributes(IMarkupWriter writer, 110 IRequestCycle cycle); 111 }