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.contrib.components; 016 017 import org.apache.tapestry.IRender; 018 import org.apache.tapestry.IRequestCycle; 019 import org.apache.tapestry.components.Conditional; 020 021 /** 022 * This component is a container for {@link When} or Otherwise components; 023 * it provides the context for mutually exclusive conditional evaluation. 024 * 025 * [<a href="../../../../../../ComponentReference/contrib.Choose.html">Component Reference</a>] 026 * 027 * @author David Solis 028 * 029 */ 030 public abstract class Choose extends Conditional { 031 032 033 public void addBody(IRender element) 034 { 035 super.addBody(element); 036 if (element instanceof When) 037 ((When) element).setChoose(this); 038 } 039 040 protected void cleanupAfterRender(IRequestCycle cycle) 041 { 042 setConditionMet(false); 043 super.cleanupAfterRender(cycle); 044 } 045 046 protected boolean evaluateCondition() 047 { 048 return getCondition(); 049 } 050 051 public boolean getInvert() 052 { 053 // This component doesn't require invert parameter. 054 return false; 055 } 056 057 public abstract boolean getCondition(); 058 059 public abstract boolean isConditionMet(); 060 public abstract void setConditionMet(boolean value); 061 }