XmlPlexusConfiguration.java
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.apache.maven.internal.xml;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.apache.maven.api.xml.XmlNode;
import org.codehaus.plexus.configuration.PlexusConfiguration;
/**
* A PlexusConfiguration implementation that wraps an XmlNode instead of copying its entire hierarchy.
* This provides better performance by avoiding deep copying of the XML structure.
*
* <p>This implementation supports both read and write operations. When write operations are performed,
* new XmlNode instances are created to maintain immutability, and internal caches are cleared.</p>
*/
public class XmlPlexusConfiguration implements PlexusConfiguration {
private XmlNode xmlNode;
private PlexusConfiguration[] childrenCache;
public static PlexusConfiguration toPlexusConfiguration(XmlNode node) {
return new XmlPlexusConfiguration(node);
}
public XmlPlexusConfiguration(XmlNode xmlNode) {
this.xmlNode = xmlNode;
}
/**
* Clears the internal cache when the XML structure is modified.
*/
private synchronized void clearCache() {
this.childrenCache = null;
}
/**
* Converts a PlexusConfiguration to an XmlNode.
*/
private XmlNode convertToXmlNode(PlexusConfiguration config) {
// Convert attributes
Map<String, String> attributes = new HashMap<>();
for (String attrName : config.getAttributeNames()) {
String attrValue = config.getAttribute(attrName);
if (attrValue != null) {
attributes.put(attrName, attrValue);
}
}
// Convert children
List<XmlNode> children = new ArrayList<>();
for (PlexusConfiguration child : config.getChildren()) {
children.add(convertToXmlNode(child));
}
return XmlNode.newInstance(config.getName(), config.getValue(), attributes, children, null);
}
@Override
public String getName() {
return xmlNode.name();
}
public synchronized void setName(String name) {
this.xmlNode = XmlNode.newBuilder()
.name(name)
.value(xmlNode.value())
.attributes(xmlNode.attributes())
.children(xmlNode.children())
.namespaceUri(xmlNode.namespaceUri())
.prefix(xmlNode.prefix())
.inputLocation(xmlNode.inputLocation())
.build();
clearCache();
}
public String getValue() {
return xmlNode.value();
}
public String getValue(String defaultValue) {
String value = xmlNode.value();
return value != null ? value : defaultValue;
}
public synchronized void setValue(String value) {
this.xmlNode = XmlNode.newBuilder()
.name(xmlNode.name())
.value(value)
.attributes(xmlNode.attributes())
.children(xmlNode.children())
.namespaceUri(xmlNode.namespaceUri())
.prefix(xmlNode.prefix())
.inputLocation(xmlNode.inputLocation())
.build();
clearCache();
}
public PlexusConfiguration setValueAndGetSelf(String value) {
setValue(value);
return this;
}
public synchronized void setAttribute(String name, String value) {
Map<String, String> newAttributes = new HashMap<>(xmlNode.attributes());
if (value == null) {
newAttributes.remove(name);
} else {
newAttributes.put(name, value);
}
this.xmlNode = XmlNode.newBuilder()
.name(xmlNode.name())
.value(xmlNode.value())
.attributes(newAttributes)
.children(xmlNode.children())
.namespaceUri(xmlNode.namespaceUri())
.prefix(xmlNode.prefix())
.inputLocation(xmlNode.inputLocation())
.build();
clearCache();
}
public String[] getAttributeNames() {
return xmlNode.attributes().keySet().toArray(new String[0]);
}
public String getAttribute(String paramName) {
return xmlNode.attribute(paramName);
}
public String getAttribute(String name, String defaultValue) {
String value = xmlNode.attribute(name);
return value != null ? value : defaultValue;
}
public PlexusConfiguration getChild(String child) {
XmlNode childNode = xmlNode.child(child);
if (childNode != null) {
return new XmlPlexusConfiguration(childNode);
} else {
// Return an empty configuration object to match DefaultPlexusConfiguration behavior
XmlNode emptyNode = XmlNode.newInstance(child, null, null, null, null);
return new XmlPlexusConfiguration(emptyNode);
}
}
public PlexusConfiguration getChild(int i) {
List<XmlNode> children = xmlNode.children();
if (i >= 0 && i < children.size()) {
return new XmlPlexusConfiguration(children.get(i));
}
return null;
}
public synchronized PlexusConfiguration getChild(String child, boolean createChild) {
XmlNode childNode = xmlNode.child(child);
if (childNode == null) {
if (createChild) {
// Create a new child node
XmlNode newChild = XmlNode.newInstance(child);
List<XmlNode> newChildren = new ArrayList<>(xmlNode.children());
newChildren.add(newChild);
this.xmlNode = XmlNode.newBuilder()
.name(xmlNode.name())
.value(xmlNode.value())
.attributes(xmlNode.attributes())
.children(newChildren)
.namespaceUri(xmlNode.namespaceUri())
.prefix(xmlNode.prefix())
.inputLocation(xmlNode.inputLocation())
.build();
clearCache();
return new XmlPlexusConfiguration(newChild);
} else {
return null; // Return null when child doesn't exist and createChild=false
}
}
return new XmlPlexusConfiguration(childNode);
}
public synchronized PlexusConfiguration[] getChildren() {
if (childrenCache == null) {
List<XmlNode> children = xmlNode.children();
childrenCache = new PlexusConfiguration[children.size()];
for (int i = 0; i < children.size(); i++) {
childrenCache[i] = new XmlPlexusConfiguration(children.get(i));
}
}
return childrenCache.clone();
}
public PlexusConfiguration[] getChildren(String name) {
List<PlexusConfiguration> result = new ArrayList<>();
for (XmlNode child : xmlNode.children()) {
if (name.equals(child.name())) {
result.add(new XmlPlexusConfiguration(child));
}
}
return result.toArray(new PlexusConfiguration[0]);
}
public synchronized void addChild(PlexusConfiguration configuration) {
// Convert PlexusConfiguration to XmlNode
XmlNode newChild = convertToXmlNode(configuration);
List<XmlNode> newChildren = new ArrayList<>(xmlNode.children());
newChildren.add(newChild);
this.xmlNode = XmlNode.newBuilder()
.name(xmlNode.name())
.value(xmlNode.value())
.attributes(xmlNode.attributes())
.children(newChildren)
.namespaceUri(xmlNode.namespaceUri())
.prefix(xmlNode.prefix())
.inputLocation(xmlNode.inputLocation())
.build();
clearCache();
}
public synchronized PlexusConfiguration addChild(String name) {
XmlNode newChild = XmlNode.newInstance(name);
List<XmlNode> newChildren = new ArrayList<>(xmlNode.children());
newChildren.add(newChild);
this.xmlNode = XmlNode.newBuilder()
.name(xmlNode.name())
.value(xmlNode.value())
.attributes(xmlNode.attributes())
.children(newChildren)
.namespaceUri(xmlNode.namespaceUri())
.prefix(xmlNode.prefix())
.inputLocation(xmlNode.inputLocation())
.build();
clearCache();
return new XmlPlexusConfiguration(newChild);
}
public synchronized PlexusConfiguration addChild(String name, String value) {
XmlNode newChild = XmlNode.newInstance(name, value);
List<XmlNode> newChildren = new ArrayList<>(xmlNode.children());
newChildren.add(newChild);
this.xmlNode = XmlNode.newBuilder()
.name(xmlNode.name())
.value(xmlNode.value())
.attributes(xmlNode.attributes())
.children(newChildren)
.namespaceUri(xmlNode.namespaceUri())
.prefix(xmlNode.prefix())
.inputLocation(xmlNode.inputLocation())
.build();
clearCache();
return new XmlPlexusConfiguration(newChild);
}
public int getChildCount() {
return xmlNode.children().size();
}
public String toString() {
final StringBuilder buf = new StringBuilder().append('<').append(getName());
for (final String a : getAttributeNames()) {
buf.append(' ').append(a).append("=\"").append(getAttribute(a)).append('"');
}
if (getChildCount() > 0) {
buf.append('>');
for (int i = 0, size = getChildCount(); i < size; i++) {
buf.append(getChild(i));
}
buf.append("</").append(getName()).append('>');
} else if (null != getValue()) {
buf.append('>').append(getValue()).append("</").append(getName()).append('>');
} else {
buf.append("/>");
}
return buf.append('\n').toString();
}
}