package net.sumaris.core.extraction.dao.technical.xml;
   
   /*-
    * #%L
    * SUMARiS:: Core Extraction
    * %%
    * Copyright (C) 2018 - 2019 SUMARiS Consortium
    * %%
    * This program is free software: you can redistribute it and/or modify
   * it under the terms of the GNU General Public License as
   * published by the Free Software Foundation, either version 3 of the
   * License, or (at your option) any later version.
   * 
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   * 
   * You should have received a copy of the GNU General Public
   * License along with this program.  If not, see
   * <http://www.gnu.org/licenses/gpl-3.0.html>.
   * #L%
   */
  
  import com.google.common.collect.Maps;
  import org.jdom2.filter.Filter;
  import org.jdom2.xpath.XPathExpression;
  import org.jdom2.xpath.XPathFactory;
  
  import java.util.List;
  import java.util.Map;
  
  /**
   * @author Benoit Lavenier <benoit.lavenier@e-is.pro>*
   */
  public class XPaths {
  
      private static final ThreadLocal<XPathFactory> factoryMapper = ThreadLocal.withInitial(XPathFactory::instance);
  
      private static final ThreadLocal<Map<String, XPathExpression<?>>> expressionMapper = ThreadLocal.withInitial(Maps::newHashMap);
  
      public static XPathFactory getThreadXPathFactory() {
          return factoryMapper.get();
      }
  
      public static <T> XPathExpression<T> compile(String expression, Filter<T> filter) {
          Map<String, XPathExpression<?>> expressionMap = expressionMapper.get();
          XPathExpression<?> xpathExpression = expressionMap.get(expressionMap);
          if (xpathExpression == null) {
              xpathExpression = getThreadXPathFactory().compile(expression, filter);
              expressionMap.put(expression, xpathExpression);
          }
          return (XPathExpression<T>)xpathExpression;
      }
  
      public static <T> List<T> evaluate(String expression, Filter<T> filter, Object object) {
          return compile(expression, filter).evaluate(object);
      }
  
      public static <T> T evaluateFirst(String expression, Filter<T> filter, Object object) {
          return compile(expression, filter).evaluateFirst(object);
      }
  }