/*
* Copyright 2005-2014 the original author or authors.
*
* 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.
*/
package org.springframework.xml.xpath;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import org.jaxen.JaxenException;
import org.jaxen.SimpleNamespaceContext;
import org.jaxen.XPath;
import org.jaxen.dom.DOMXPath;
import org.w3c.dom.DOMException;
import org.w3c.dom.Node;
/**
* Jaxen-specific factory for creating {@code XPathExpression}s.
*
* @author Arjen Poutsma
* @see #createXPathExpression(String)
* @since 1.0.0
*/
abstract class JaxenXPathExpressionFactory {
/**
* Creates a Jaxen {@code XPathExpression} from the given string expression.
*
* @param expression the XPath expression
* @return the compiled {@code XPathExpression}
* @throws XPathParseException when the given expression cannot be parsed
*/
static XPathExpression createXPathExpression(String expression) {
try {
XPath xpath = new DOMXPath(expression);
return new JaxenXpathExpression(xpath);
}
catch (JaxenException ex) {
throw new org.springframework.xml.xpath.XPathParseException(
"Could not compile [" + expression + "] to a XPathExpression: " + ex.getMessage(), ex);
}
}
/**
* Creates a Jaxen {@code XPathExpression} from the given string expression and prefixes.
*
* @param expression the XPath expression
* @param namespaces the namespaces
* @return the compiled {@code XPathExpression}
* @throws XPathParseException when the given expression cannot be parsed
*/
public static XPathExpression createXPathExpression(String expression, Map<String, String> namespaces) {
try {
XPath xpath = new DOMXPath(expression);
xpath.setNamespaceContext(new SimpleNamespaceContext(namespaces));
return new JaxenXpathExpression(xpath);
}
catch (JaxenException ex) {
throw new org.springframework.xml.xpath.XPathParseException(
"Could not compile [" + expression + "] to a XPathExpression: " + ex.getMessage(), ex);
}
}
/** Jaxen implementation of the {@code XPathExpression} interface. */
private static class JaxenXpathExpression implements XPathExpression {
private XPath xpath;
private JaxenXpathExpression(XPath xpath) {
this.xpath = xpath;
}
@Override
public Node evaluateAsNode(Node node) {
try {
return (Node) xpath.selectSingleNode(node);
}
catch (JaxenException ex) {
throw new XPathException("Could not evaluate XPath expression [" + xpath + "] :" + ex.getMessage(), ex);
}
}
@Override
public boolean evaluateAsBoolean(Node node) {
try {
return xpath.booleanValueOf(node);
}
catch (JaxenException ex) {
throw new XPathException("Could not evaluate XPath expression [" + xpath + "] :" + ex.getMessage(), ex);
}
}
@Override
public double evaluateAsNumber(Node node) {
try {
return xpath.numberValueOf(node).doubleValue();
}
catch (JaxenException ex) {
throw new XPathException("Could not evaluate XPath expression [" + xpath + "] :" + ex.getMessage(), ex);
}
}
@Override
public String evaluateAsString(Node node) {
try {
return xpath.stringValueOf(node);
}
catch (JaxenException ex) {
throw new XPathException("Could not evaluate XPath expression [" + xpath + "] :" + ex.getMessage(), ex);
}
}
@Override
@SuppressWarnings("unchecked")
public List<Node> evaluateAsNodeList(Node node) {
try {
return xpath.selectNodes(node);
}
catch (JaxenException ex) {
throw new XPathException("Could not evaluate XPath expression [" + xpath + "] :" + ex.getMessage(), ex);
}
}
@Override
public <T> T evaluateAsObject(Node context, NodeMapper<T> nodeMapper) throws XPathException {
try {
Node result = (Node) xpath.selectSingleNode(context);
if (result != null) {
try {
return nodeMapper.mapNode(result, 0);
}
catch (DOMException ex) {
throw new XPathException("Mapping resulted in DOMException", ex);
}
}
else {
return null;
}
}
catch (JaxenException ex) {
throw new XPathException("Could not evaluate XPath expression [" + xpath + "] :" + ex.getMessage(), ex);
}
}
@Override
public <T> List<T> evaluate(Node context, NodeMapper<T> nodeMapper) throws XPathException {
try {
List<?> nodes = xpath.selectNodes(context);
List<T> results = new ArrayList<T>(nodes.size());
for (int i = 0; i < nodes.size(); i++) {
Node node = (Node) nodes.get(i);
try {
results.add(nodeMapper.mapNode(node, i));
}
catch (DOMException ex) {
throw new XPathException("Mapping resulted in DOMException", ex);
}
}
return results;
}
catch (JaxenException ex) {
throw new XPathException("Could not evaluate XPath expression [" + xpath + "] :" + ex.getMessage(), ex);
}
}
}
}