001/** 002 * 003 * Copyright (c) 2014, the Railo Company Ltd. All rights reserved. 004 * 005 * This library is free software; you can redistribute it and/or 006 * modify it under the terms of the GNU Lesser General Public 007 * License as published by the Free Software Foundation; either 008 * version 2.1 of the License, or (at your option) any later version. 009 * 010 * This library is distributed in the hope that it will be useful, 011 * but WITHOUT ANY WARRANTY; without even the implied warranty of 012 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 013 * Lesser General Public License for more details. 014 * 015 * You should have received a copy of the GNU Lesser General Public 016 * License along with this library. If not, see <http://www.gnu.org/licenses/>. 017 * 018 **/ 019package lucee.runtime.tag; 020 021import java.util.Queue; 022import java.util.concurrent.ConcurrentHashMap; 023import java.util.concurrent.ConcurrentLinkedQueue; 024 025import javax.servlet.jsp.tagext.Tag; 026 027import lucee.commons.lang.ClassUtil; 028import lucee.runtime.config.ConfigWeb; 029import lucee.runtime.exp.ExpressionException; 030import lucee.runtime.exp.PageException; 031import lucee.runtime.op.Caster; 032 033// TODO kann man nicht auf context ebene 034 035/** 036 * Pool to Handle Tags 037 */ 038public final class TagHandlerPool { 039 private ConcurrentHashMap<String,Queue<Tag>> map=new ConcurrentHashMap<String,Queue<Tag>>(); 040 private ConfigWeb config; 041 042 public TagHandlerPool(ConfigWeb config) { 043 this.config=config; 044 } 045 046 /** 047 * return a tag to use from a class 048 * @param tagClass 049 * @return Tag 050 * @throws PageException 051 */ 052 public Tag use(String tagClass) throws PageException { 053 Queue<Tag> queue = getQueue(tagClass); 054 Tag tag = queue.poll(); 055 if(tag!=null) return tag; 056 return loadTag(tagClass); 057 } 058 059 /** 060 * free a tag for reusing 061 * @param tag 062 * @throws ExpressionException 063 */ 064 public void reuse(Tag tag) { 065 tag.release(); 066 Queue<Tag> queue = getQueue(tag.getClass().getName()); 067 queue.add(tag); 068 } 069 070 071 private Tag loadTag(String tagClass) throws PageException { 072 try { 073 Class<Tag> clazz = ClassUtil.loadClass(config.getClassLoader(),tagClass); 074 return clazz.newInstance(); 075 } 076 catch (Exception e) { 077 throw Caster.toPageException(e); 078 } 079 } 080 081 private Queue<Tag> getQueue(String tagClass) { 082 Queue<Tag> queue = map.get(tagClass);// doing get before, do avoid constructing ConcurrentLinkedQueue Object all the time 083 if(queue!=null) return queue; 084 Queue<Tag> nq,oq; 085 oq=map.putIfAbsent(tagClass, nq=new ConcurrentLinkedQueue<Tag>()); 086 if(oq!=null) return oq; 087 return nq; 088 089 } 090 091 public void reset() { 092 map.clear(); 093 } 094}