net.sf.jasperreports.engine.util.xml.JaxenNsAwareXPathExecuter.java Source code

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Here is the source code for net.sf.jasperreports.engine.util.xml.JaxenNsAwareXPathExecuter.java

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/*
 * JasperReports - Free Java Reporting Library.
 * Copyright (C) 2001 - 2019 TIBCO Software Inc. All rights reserved.
 * http://www.jaspersoft.com
 *
 * Unless you have purchased a commercial license agreement from Jaspersoft,
 * the following license terms apply:
 *
 * This program is part of JasperReports.
 *
 * JasperReports is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * JasperReports 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with JasperReports. If not, see <http://www.gnu.org/licenses/>.
 */
package net.sf.jasperreports.engine.util.xml;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.apache.commons.collections4.map.ReferenceMap;
import org.jaxen.JaxenException;
import org.jaxen.NamespaceContext;
import org.jaxen.XPath;
import org.jaxen.dom.DOMXPath;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;

import net.sf.jasperreports.engine.JRException;

/**
 * XPath executer implementation that uses a namespace aware <a href="http://jaxen.org/" target="_blank">Jaxen</a>.
 * 
 * @author Narcis Marcu (narcism@users.sourceforge.net)
 */
public class JaxenNsAwareXPathExecuter extends JaxenXPathExecuter {
    private final Map<String, XPath> cachedXPaths = new ReferenceMap<String, XPath>();//soft cache

    private Map<String, String> xmlNamespaceMap;

    private NamespaceContext context;

    boolean detectXmlNamespaces;

    /**
     * Default constructor.
     */
    public JaxenNsAwareXPathExecuter() {
    }

    public Map<String, String> getXmlNamespaceMap() {
        return xmlNamespaceMap;
    }

    public void setXmlNamespaceMap(Map<String, String> xmlNamespaceMap) throws JRException {
        this.xmlNamespaceMap = xmlNamespaceMap;
    }

    public boolean getDetectXmlNamespaces() {
        return detectXmlNamespaces;
    }

    public void setDetectXmlNamespaces(boolean detectXmlNamespaces) {
        this.detectXmlNamespaces = detectXmlNamespaces;
    }

    protected XPath getXPath(Node contextNode, String expression) throws JRException {
        XPath xPath = cachedXPaths.get(expression);
        if (xPath == null) {
            try {
                xPath = new DOMXPath(expression);
                addNamespaceContext(contextNode, xPath, expression);
            } catch (JaxenException e) {
                throw new JRException(EXCEPTION_MESSAGE_KEY_XPATH_COMPILATION_FAILURE, new Object[] { expression },
                        e);
            }
            cachedXPaths.put(expression, xPath);
        }
        return xPath;
    }

    @Override
    public NodeList selectNodeList(Node contextNode, String expression) throws JRException {
        try {
            XPath xpath = getXPath(contextNode, expression);
            Object object = xpath.evaluate(contextNode);
            List<Object> nodes;
            if (object instanceof List<?>) {
                nodes = (List<Object>) object;
            } else {
                nodes = new ArrayList<Object>();
                nodes.add(object);
            }
            return new NodeListWrapper(nodes);
        } catch (JaxenException e) {
            throw new JRException(EXCEPTION_MESSAGE_KEY_XPATH_SELECTION_FAILURE, new Object[] { expression }, e);
        }
    }

    @Override
    public Object selectObject(Node contextNode, String expression) throws JRException {
        try {
            XPath xpath = getXPath(contextNode, expression);
            Object object = xpath.evaluate(contextNode);
            Object value;
            if (object instanceof List<?>) {
                List<?> list = (List<?>) object;
                if (list.isEmpty()) {
                    value = null;
                } else {
                    value = list.get(0);
                }
            } else if (object instanceof Number || object instanceof Boolean) {
                value = object;
            } else {
                value = object.toString();
            }
            return value;
        } catch (JaxenException e) {
            throw new JRException(EXCEPTION_MESSAGE_KEY_XPATH_SELECTION_FAILURE, new Object[] { expression }, e);
        }
    }

    protected boolean containsPrefixes(String expression) {
        String[] tokens = expression.split("::");
        for (String token : tokens) {
            if (token.indexOf(":") != -1) {
                return true;
            }
        }
        return false;
    }

    private Map<String, String> extractXmlNamespaces(Node contextNode) throws JRException {
        Map<String, String> namespaces = new HashMap<String, String>();
        List<Node> nlist;
        String namespaceXPathString = "//namespace::node()";

        try {
            XPath xpath = new DOMXPath(namespaceXPathString);
            nlist = xpath.selectNodes(contextNode);

            for (int i = 0; i < nlist.size(); i++) {
                Node node = nlist.get(i);
                if (node.getParentNode() != null && node.getParentNode().getPrefix() != null) {
                    if (!namespaces.containsKey(node.getParentNode().getPrefix())) {
                        namespaces.put(node.getParentNode().getPrefix(), node.getParentNode().getNamespaceURI());
                    }
                }
            }

        } catch (JaxenException e) {
            throw new JRException(EXCEPTION_MESSAGE_KEY_XPATH_SELECTION_FAILURE,
                    new Object[] { namespaceXPathString }, e);
        }

        return namespaces;
    }

    protected void addNamespaceContext(Node contextNode, XPath xPath, String expression) throws JRException {
        if (xmlNamespaceMap == null && detectXmlNamespaces && containsPrefixes(expression) && context == null) {
            xmlNamespaceMap = extractXmlNamespaces(contextNode);
        }

        if (xmlNamespaceMap != null && xmlNamespaceMap.size() > 0) {
            if (context == null) {
                context = new NamespaceContext() {

                    @Override
                    public String translateNamespacePrefixToUri(String prefix) {
                        return xmlNamespaceMap.get(prefix);
                    }
                };
            }
            xPath.setNamespaceContext(context);
        }
    }

}