1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one or more 3 * contributor license agreements. See the NOTICE file distributed with 4 * this work for additional information regarding copyright ownership. 5 * The ASF licenses this file to You under the Apache License, Version 2.0 6 * (the "License"); you may not use this file except in compliance with 7 * the License. You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 */ 17 18 19 package org.apache.struts2.jasper.tagplugins.jstl.core; 20 21 import org.apache.struts2.jasper.compiler.tagplugin.TagPlugin; 22 import org.apache.struts2.jasper.compiler.tagplugin.TagPluginContext; 23 24 public final class When implements TagPlugin { 25 26 public void doTag(TagPluginContext ctxt) { 27 // Get the parent context to determine if this is the first <c:when> 28 TagPluginContext parentContext = ctxt.getParentContext(); 29 if (parentContext == null) { 30 ctxt.dontUseTagPlugin(); 31 return; 32 } 33 34 if ("true".equals(parentContext.getPluginAttribute("hasBeenHere"))) { 35 ctxt.generateJavaSource("} else if("); 36 // See comment below for the reason we generate the extra "}" here. 37 } else { 38 ctxt.generateJavaSource("if("); 39 parentContext.setPluginAttribute("hasBeenHere", "true"); 40 } 41 ctxt.generateAttribute("test"); 42 ctxt.generateJavaSource("){"); 43 ctxt.generateBody(); 44 45 // We don't generate the closing "}" for the "if" here because there 46 // may be whitespaces in between <c:when>'s. Instead we delay 47 // generating it until the next <c:when> or <c:otherwise> or 48 // <c:choose> 49 } 50 }