/*
* Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code 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
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package com.sun.org.apache.xpath.internal.jaxp;
import com.sun.org.apache.xpath.internal.objects.XObject;
import java.util.Objects;
import javax.xml.transform.TransformerException;
import javax.xml.xpath.XPathNodes;
import javax.xml.xpath.XPathEvaluationResult;
import javax.xml.xpath.XPathEvaluationResult.XPathResultType;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.w3c.dom.traversal.NodeIterator;
/**
* This is the implementation of XPathEvaluationResult that represents the
* result of the evaluation of an XPath expression within the context of a
* particular node.
*/
class XPathResultImpl<T> implements XPathEvaluationResult<T> {
XObject resultObject;
int resultType;
Class<T> type;
XPathResultType mapToType;
NodeList nodeList = null;
int currentIndex;
Node currentNode;
boolean boolValue = false;
Node node = null;
double numValue;
String strValue;
/**
* Construct an XPathEvaluationResult object.
*
* @param resultObject internal XPath result object
* @param type class type
* @throws TransformerException if there is an error reading the XPath
* result.
*/
public XPathResultImpl(XObject resultObject, Class<T> type)
throws TransformerException {
this.resultObject = resultObject;
resultType = resultObject.getType();
this.type = type;
getResult(resultObject);
}
/**
* Return the result type as an enum specified by {@code XPathResultType}
* @return the result type
*/
@Override
public XPathResultType type() {
return mapToType;
}
/**
* Returns the value of the result as the type <T> specified for the class.
*
* @return The value of the result.
*/
@Override
public T value() {
Objects.requireNonNull(type);
try {
return getValue(resultObject, type);
} catch (TransformerException ex) {
throw new RuntimeException(ex);
}
}
/**
* Read the XObject and set values in accordance with the result type
* @param resultObject internal XPath result object
* @throws TransformerException if there is an error reading the XPath
* result.
*/
private void getResult(XObject resultObject) throws TransformerException {
switch (resultType) {
case XObject.CLASS_BOOLEAN:
boolValue = resultObject.bool();
mapToType = XPathResultType.BOOLEAN;
break;
case XObject.CLASS_NUMBER:
numValue = resultObject.num();
mapToType = XPathResultType.NUMBER;
break;
case XObject.CLASS_STRING:
strValue = resultObject.str();
mapToType = XPathResultType.STRING;
break;
case XObject.CLASS_NODESET:
mapToType = XPathResultType.NODESET;
nodeList = resultObject.nodelist();
break;
case XObject.CLASS_RTREEFRAG: //NODE
mapToType = XPathResultType.NODE;
NodeIterator ni = resultObject.nodeset();
//Return the first node, or null
node = ni.nextNode();
break;
}
}
/**
* Read the internal result object and return the value in accordance with
* the type specified.
*
* @param <T> The expected class type.
* @param resultObject internal XPath result object
* @param type the class type
* @return The value of the result, null in case of unexpected type.
* @throws TransformerException if there is an error reading the XPath
* result.
*/
static <T> T getValue(XObject resultObject, Class<T> type) throws TransformerException {
Objects.requireNonNull(type);
if (type.isAssignableFrom(XPathEvaluationResult.class)) {
return type.cast(new XPathResultImpl<T>(resultObject, type));
}
int resultType = classToInternalType(type);
switch (resultType) {
case XObject.CLASS_BOOLEAN:
return type.cast(resultObject.bool());
case XObject.CLASS_NUMBER:
if (Double.class.isAssignableFrom(type)) {
return type.cast(resultObject.num());
} else if (Integer.class.isAssignableFrom(type)) {
return type.cast((int)resultObject.num());
} else if (Long.class.isAssignableFrom(type)) {
return type.cast((long)resultObject.num());
}
/*
This is to suppress warnings. By the current specification,
among numeric types, only Double, Integer and Long are supported.
*/
break;
case XObject.CLASS_STRING:
return type.cast(resultObject.str());
case XObject.CLASS_NODESET:
XPathNodes nodeSet = new XPathNodesImpl(resultObject.nodelist(),
Node.class);
return type.cast(nodeSet);
case XObject.CLASS_RTREEFRAG: //NODE
NodeIterator ni = resultObject.nodeset();
//Return the first node, or null
return type.cast(ni.nextNode());
}
return null;
}
/**
* Map the specified class type to the internal result type
*
* @param <T> The expected class type.
* @param type the class type
* @return the internal XObject type.
*/
static <T> int classToInternalType(Class<T> type) {
if (type.isAssignableFrom(Boolean.class)) {
return XObject.CLASS_BOOLEAN;
} else if (Number.class.isAssignableFrom(type)) {
return XObject.CLASS_NUMBER;
} else if (type.isAssignableFrom(String.class)) {
return XObject.CLASS_STRING;
} else if (type.isAssignableFrom(XPathNodes.class)) {
return XObject.CLASS_NODESET;
} else if (type.isAssignableFrom(Node.class)) {
return XObject.CLASS_RTREEFRAG;
}
return XObject.CLASS_NULL;
}
}