it.tidalwave.xml.jaxp.JaxpXPath Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of it-tidalwave-xml Show documentation
The newest version!
/***********************************************************************************************************************
 *
 * blueBill Core - open source birding
 * Copyright (C) 2009-2011 by Tidalwave s.a.s. (http://www.tidalwave.it)
 *
 ***********************************************************************************************************************
 *
 * Licensed 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.
 *
 ***********************************************************************************************************************
 *
 * WWW: http://bluebill.tidalwave.it
 * SCM: https://java.net/hg/bluebill~core-src
 *
 **********************************************************************************************************************/
package it.tidalwave.xml.jaxp;

import javax.annotation.Nonnull;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import javax.annotation.CheckForNull;
import javax.xml.XMLConstants;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpression;
import javax.xml.xpath.XPathExpressionException;
import javax.xml.xpath.XPathFactory;
import org.w3c.dom.NodeList;
import org.jaxen.FunctionContext;
import org.jaxen.JaxenException;
import org.jaxen.NamespaceContext;
import org.jaxen.Navigator;
import org.jaxen.VariableContext;
import org.jaxen.XPath;

/***********************************************************************************************************************
 *
 * @author  Fabrizio Giudici
 * @version $Id$
 *
 **********************************************************************************************************************/
public class JaxpXPath implements XPath
  {
    private final static javax.xml.xpath.XPath JAXP_XPATH;
    private final XPathExpression xPathExpression;
    private final static Map PREFIX_TO_NAMESPACE_MAP = new HashMap();
    private final static Map NAMESPACE_TO_PREFIX_MAP = new HashMap();

    static
      {
        final XPathFactory xPathFactory = XPathFactory.newInstance();
        JAXP_XPATH = xPathFactory.newXPath();
        JAXP_XPATH.setNamespaceContext(new javax.xml.namespace.NamespaceContext()
          {
            @Nonnull
            public String getNamespaceURI (final @Nonnull String prefix)
              {
                final String nameSpace = PREFIX_TO_NAMESPACE_MAP.get(prefix);
                return (nameSpace != null) ? nameSpace : XMLConstants.NULL_NS_URI;
              }

            @CheckForNull
            public String getPrefix (final @Nonnull String nameSpace)
              {
                return NAMESPACE_TO_PREFIX_MAP.get(nameSpace);
              }

            @Nonnull
            public Iterator getPrefixes (final @Nonnull String nameSpace)
              {
                final String prefix = getPrefix(nameSpace);
                return ((prefix == null) ? Collections.emptyList() : Collections.singletonList(prefix)).iterator();
              }
          });

        PREFIX_TO_NAMESPACE_MAP.put("html", "http://www.w3.org/1999/xhtml");
        NAMESPACE_TO_PREFIX_MAP.put("http://www.w3.org/1999/xhtml", "html");
      }

    public JaxpXPath (final @Nonnull String expression)
      throws JaxenException
      {
        try
          {
            xPathExpression = JAXP_XPATH.compile(expression);
          }
        catch (XPathExpressionException e)
          {
            throw new JaxenException(e);
          }
      }

    public Object evaluate (final @Nonnull Object o)
      throws JaxenException
      {
        try
          {
            return xPathExpression.evaluate(o);
          }
        catch (XPathExpressionException e)
          {
            throw new JaxenException(e);
          }
      }

    @Deprecated
    public String valueOf (final @Nonnull Object o)
      throws JaxenException
      {
        return stringValueOf(o);
      }

    public String stringValueOf (final @Nonnull Object o)
      throws JaxenException
      {
        try
          {
            return (String)xPathExpression.evaluate(o, XPathConstants.STRING);
          }
        catch (XPathExpressionException e)
          {
            throw new JaxenException(e);
          }
      }

    public boolean booleanValueOf (final @Nonnull Object o)
      throws JaxenException
      {
        try
          {
            return (Boolean)xPathExpression.evaluate(o, XPathConstants.BOOLEAN);
          }
        catch (XPathExpressionException e)
          {
            throw new JaxenException(e);
          }
      }

    public Number numberValueOf (final @Nonnull Object o)
      throws JaxenException
      {
        try
          {
            return (Number)xPathExpression.evaluate(o, XPathConstants.NUMBER);
          }
        catch (XPathExpressionException e)
          {
            throw new JaxenException(e);
          }
      }

    public List selectNodes (final @Nonnull Object o)
      throws JaxenException
      {
        try
          {
            final NodeList nodeList = (NodeList)xPathExpression.evaluate(o, XPathConstants.NODESET);
            final List