| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package org.apache.taglibs.standard.tag.common.core; |
| |
| import java.util.StringTokenizer; |
| |
| import jakarta.el.ValueExpression; |
| import jakarta.servlet.jsp.JspTagException; |
| import jakarta.servlet.jsp.jstl.core.IteratedExpression; |
| import jakarta.servlet.jsp.jstl.core.IteratedValueExpression; |
| import jakarta.servlet.jsp.jstl.core.LoopTagSupport; |
| |
| /** |
| * <p>Support for tag handlers for <forTokens>, the tokenizing |
| * iteration tag in JSTL 1.0. This class extends LoopTagSupport and |
| * provides ForTokens-specific functionality. The rtexprvalue and |
| * expression-evaluating libraries each have handlers that extend this |
| * class.</p> |
| * |
| * @author Shawn Bayern |
| * @see jakarta.servlet.jsp.jstl.core.LoopTagSupport |
| */ |
| |
| public abstract class ForTokensSupport extends LoopTagSupport { |
| |
| //********************************************************************* |
| // Implementation overview |
| |
| /* |
| * This handler simply constructs a StringTokenizer based on its input |
| * and relays tokens to the iteration implementation that it inherits. |
| * The 'items' and 'delims' attributes are expected to be provided by |
| * a subtag (presumably in the rtexprvalue or expression-evaluating |
| * versions of the JSTL library). |
| */ |
| |
| |
| //********************************************************************* |
| // ForEachTokens-specific state (protected) |
| |
| protected Object items; // 'items' attribute |
| protected String delims; // 'delims' attribute |
| protected StringTokenizer st; // digested tokenizer |
| protected int currentIndex; |
| private IteratedExpression itemsValueIteratedExpression; |
| |
| |
| //********************************************************************* |
| // Iteration control methods |
| |
| /* |
| * These just create and use a StringTokenizer. |
| * We inherit semantics and Javadoc from LoopTagSupport. |
| */ |
| |
| @Override |
| protected void prepare() throws JspTagException { |
| if (items instanceof ValueExpression) { |
| deferredExpression = (ValueExpression) items; |
| itemsValueIteratedExpression = new IteratedExpression(deferredExpression, getDelims()); |
| currentIndex = 0; |
| |
| Object originalValue = deferredExpression.getValue(pageContext.getELContext()); |
| if (originalValue instanceof String) { |
| st = new StringTokenizer((String) originalValue, delims); |
| } else { |
| throw new JspTagException(); |
| } |
| } else { |
| st = new StringTokenizer((String) items, delims); |
| } |
| } |
| |
| @Override |
| protected boolean hasNext() throws JspTagException { |
| return st.hasMoreElements(); |
| } |
| |
| @Override |
| protected Object next() throws JspTagException { |
| if (deferredExpression != null) { |
| st.nextElement(); |
| return new IteratedValueExpression(itemsValueIteratedExpression, currentIndex++); |
| } else { |
| return st.nextElement(); |
| } |
| } |
| |
| |
| //********************************************************************* |
| // Tag logic and lifecycle management |
| |
| |
| // Releases any resources we may have (or inherit) |
| |
| @Override |
| public void release() { |
| super.release(); |
| items = delims = null; |
| st = null; |
| } |
| |
| /** |
| * Get the delimiter for string tokens. Used only for constructing |
| * the deferred expression for it. |
| */ |
| @Override |
| protected String getDelims() { |
| return delims; |
| } |
| } |