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/**
* Copyright (c) 2012-2017, jcabi.com
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met: 1) Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer. 2) Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided
* with the distribution. 3) Neither the name of the jcabi.com nor
* the names of its contributors may be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT
* NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
* THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package com.jcabi.xml;
import com.jcabi.immutable.Array;
import com.jcabi.immutable.ArrayMap;
import com.jcabi.log.Logger;
import java.util.Collections;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
import javax.xml.XMLConstants;
import javax.xml.namespace.NamespaceContext;
import lombok.EqualsAndHashCode;
/**
* Convenient internal implementation of {@link NamespaceContext}.
*
* The class is immutable and thread-safe.
*
* @author Yegor Bugayenko ([email protected])
* @version $Id: ffd6d7b645704aa2ace35600286938b7a7b92357 $
* @since 0.1
*/
@EqualsAndHashCode(of = { "map", "contexts" })
public final class XPathContext implements NamespaceContext {
/**
* Map of prefixes and URIs.
*/
private final transient ArrayMap map;
/**
* List of contexts to use.
*/
private final transient Array contexts;
/**
* Public ctor.
*
* Since this class is private in the package users won't be able
* to see this code and its documentation. That's why all these prefixes
* and namespaces should be documented in
* {@link XMLDocument#XMLDocument(String)} ctor. When adding/changing this
* list - don't forget to document it there.
*/
public XPathContext() {
this(
new ArrayMap()
.with("xhtml", "http://www.w3.org/1999/xhtml")
.with("xs", "http://www.w3.org/2001/XMLSchema")
.with("xsi", "http://www.w3.org/2001/XMLSchema-instance")
.with("xsl", "http://www.w3.org/1999/XSL/Transform")
.with("svg", "http://www.w3.org/2000/svg"),
new Array()
);
}
/**
* Public ctor with custom namespaces.
* @param namespaces List of namespaces
*/
public XPathContext(final Object... namespaces) {
this(
XPathContext.namespacesAsMap(namespaces),
new Array()
);
}
/**
* Public ctor.
* @param old Old map of prefixes and namespaces
* @param prefix The prefix
* @param namespace The namespace
*/
private XPathContext(final ArrayMap old,
final String prefix, final Object namespace) {
this(
old.with(prefix, namespace.toString()),
new Array()
);
}
/**
* Private ctor.
* @param mapping Mapping to set.
* @param ctxs Context to set.
*/
private XPathContext(final ArrayMap mapping,
final Array ctxs) {
this.map = mapping;
this.contexts = ctxs;
}
@Override
public String toString() {
return this.map.keySet().toString();
}
@Override
public String getNamespaceURI(final String prefix) {
String namespace = this.map.get(prefix);
if (namespace == null) {
for (final NamespaceContext ctx : this.contexts) {
namespace = ctx.getNamespaceURI(prefix);
if (namespace != null) {
break;
}
}
}
if (namespace == null) {
if (prefix.equals(XMLConstants.XML_NS_PREFIX)) {
namespace = XMLConstants.XML_NS_URI;
} else if (prefix.equals(XMLConstants.XMLNS_ATTRIBUTE)) {
namespace = XMLConstants.XMLNS_ATTRIBUTE_NS_URI;
} else {
namespace = XMLConstants.NULL_NS_URI;
}
}
return namespace;
}
@Override
public String getPrefix(final String namespace) {
final Iterator prefixes = this.getPrefixes(namespace);
String prefix = null;
if (prefixes.hasNext()) {
prefix = prefixes.next();
}
return prefix;
}
@Override
public Iterator getPrefixes(final String namespace) {
final List prefixes = new LinkedList<>();
for (final ConcurrentMap.Entry entry
: this.map.entrySet()) {
if (entry.getValue().equals(namespace)) {
prefixes.add(entry.getKey());
}
}
for (final NamespaceContext ctx : this.contexts) {
final Iterator iterator = ctx.getPrefixes(namespace);
while (iterator.hasNext()) {
prefixes.add(iterator.next().toString());
}
}
if (namespace.equals(XMLConstants.XML_NS_URI)) {
prefixes.add(XMLConstants.XML_NS_PREFIX);
}
if (namespace.equals(XMLConstants.XMLNS_ATTRIBUTE_NS_URI)) {
prefixes.add(XMLConstants.XMLNS_ATTRIBUTE);
}
return Collections.unmodifiableList(prefixes).iterator();
}
/**
* Add new prefix and namespace.
* @param prefix The prefix
* @param namespace The namespace
* @return New context
*/
public XPathContext add(final String prefix, final Object namespace) {
if (this.map.containsKey(prefix)) {
throw new IllegalArgumentException(
String.format(
"prefix '%s' already registered for namespace '%s'",
prefix,
this.map.get(prefix)
)
);
}
return new XPathContext(this.map, prefix, namespace);
}
/**
* Add new context.
* @param context The context to merge into this one
* @return New context
*/
public XPathContext merge(final NamespaceContext context) {
return new XPathContext(
this.map, this.contexts.with(context)
);
}
/**
* Get namespaces as map.
* @param namespaces The namespaces
* @return Namespaces as map
*/
private static ArrayMap namespacesAsMap(
final Object...namespaces) {
final ConcurrentMap map =
new ConcurrentHashMap<>(namespaces.length);
for (int pos = 0; pos < namespaces.length; ++pos) {
map.put(
Logger.format("ns%d", pos + 1),
namespaces[pos].toString()
);
}
return new ArrayMap<>(map);
}
}