org.springframework.util.xml.AbstractStaxXMLReader Maven / Gradle / Ivy
/*
* Copyright 2002-2019 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
*
* https://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.util.xml;
import java.util.LinkedHashMap;
import java.util.Map;
import javax.xml.namespace.QName;
import javax.xml.stream.Location;
import javax.xml.stream.XMLStreamException;
import org.xml.sax.InputSource;
import org.xml.sax.Locator;
import org.xml.sax.SAXException;
import org.xml.sax.SAXNotRecognizedException;
import org.xml.sax.SAXNotSupportedException;
import org.xml.sax.SAXParseException;
import org.springframework.lang.Nullable;
import org.springframework.util.StringUtils;
/**
* Abstract base class for SAX {@code XMLReader} implementations that use StAX as a basis.
*
* @author Arjen Poutsma
* @author Juergen Hoeller
* @since 3.0
* @see #setContentHandler(org.xml.sax.ContentHandler)
* @see #setDTDHandler(org.xml.sax.DTDHandler)
* @see #setEntityResolver(org.xml.sax.EntityResolver)
* @see #setErrorHandler(org.xml.sax.ErrorHandler)
*/
abstract class AbstractStaxXMLReader extends AbstractXMLReader {
private static final String NAMESPACES_FEATURE_NAME = "http://xml.org/sax/features/namespaces";
private static final String NAMESPACE_PREFIXES_FEATURE_NAME = "http://xml.org/sax/features/namespace-prefixes";
private static final String IS_STANDALONE_FEATURE_NAME = "http://xml.org/sax/features/is-standalone";
private boolean namespacesFeature = true;
private boolean namespacePrefixesFeature = false;
@Nullable
private Boolean isStandalone;
private final Map namespaces = new LinkedHashMap<>();
@Override
public boolean getFeature(String name) throws SAXNotRecognizedException, SAXNotSupportedException {
switch (name) {
case NAMESPACES_FEATURE_NAME:
return this.namespacesFeature;
case NAMESPACE_PREFIXES_FEATURE_NAME:
return this.namespacePrefixesFeature;
case IS_STANDALONE_FEATURE_NAME:
if (this.isStandalone != null) {
return this.isStandalone;
}
else {
throw new SAXNotSupportedException("startDocument() callback not completed yet");
}
default:
return super.getFeature(name);
}
}
@Override
public void setFeature(String name, boolean value) throws SAXNotRecognizedException, SAXNotSupportedException {
if (NAMESPACES_FEATURE_NAME.equals(name)) {
this.namespacesFeature = value;
}
else if (NAMESPACE_PREFIXES_FEATURE_NAME.equals(name)) {
this.namespacePrefixesFeature = value;
}
else {
super.setFeature(name, value);
}
}
protected void setStandalone(boolean standalone) {
this.isStandalone = standalone;
}
/**
* Indicates whether the SAX feature {@code http://xml.org/sax/features/namespaces} is turned on.
*/
protected boolean hasNamespacesFeature() {
return this.namespacesFeature;
}
/**
* Indicates whether the SAX feature {@code http://xml.org/sax/features/namespaces-prefixes} is turned on.
*/
protected boolean hasNamespacePrefixesFeature() {
return this.namespacePrefixesFeature;
}
/**
* Convert a {@code QName} to a qualified name, as used by DOM and SAX.
* The returned string has a format of {@code prefix:localName} if the
* prefix is set, or just {@code localName} if not.
* @param qName the {@code QName}
* @return the qualified name
*/
protected String toQualifiedName(QName qName) {
String prefix = qName.getPrefix();
if (!StringUtils.hasLength(prefix)) {
return qName.getLocalPart();
}
else {
return prefix + ":" + qName.getLocalPart();
}
}
/**
* Parse the StAX XML reader passed at construction-time.
* NOTE:: The given {@code InputSource} is not read, but ignored.
* @param ignored is ignored
* @throws SAXException a SAX exception, possibly wrapping a {@code XMLStreamException}
*/
@Override
public final void parse(InputSource ignored) throws SAXException {
parse();
}
/**
* Parse the StAX XML reader passed at construction-time.
*
NOTE:: The given system identifier is not read, but ignored.
* @param ignored is ignored
* @throws SAXException a SAX exception, possibly wrapping a {@code XMLStreamException}
*/
@Override
public final void parse(String ignored) throws SAXException {
parse();
}
private void parse() throws SAXException {
try {
parseInternal();
}
catch (XMLStreamException ex) {
Locator locator = null;
if (ex.getLocation() != null) {
locator = new StaxLocator(ex.getLocation());
}
SAXParseException saxException = new SAXParseException(ex.getMessage(), locator, ex);
if (getErrorHandler() != null) {
getErrorHandler().fatalError(saxException);
}
else {
throw saxException;
}
}
}
/**
* Template method that parses the StAX reader passed at construction-time.
*/
protected abstract void parseInternal() throws SAXException, XMLStreamException;
/**
* Start the prefix mapping for the given prefix.
* @see org.xml.sax.ContentHandler#startPrefixMapping(String, String)
*/
protected void startPrefixMapping(@Nullable String prefix, String namespace) throws SAXException {
if (getContentHandler() != null && StringUtils.hasLength(namespace)) {
if (prefix == null) {
prefix = "";
}
if (!namespace.equals(this.namespaces.get(prefix))) {
getContentHandler().startPrefixMapping(prefix, namespace);
this.namespaces.put(prefix, namespace);
}
}
}
/**
* End the prefix mapping for the given prefix.
* @see org.xml.sax.ContentHandler#endPrefixMapping(String)
*/
protected void endPrefixMapping(String prefix) throws SAXException {
if (getContentHandler() != null && this.namespaces.containsKey(prefix)) {
getContentHandler().endPrefixMapping(prefix);
this.namespaces.remove(prefix);
}
}
/**
* Implementation of the {@code Locator} interface based on a given StAX {@code Location}.
* @see Locator
* @see Location
*/
private static class StaxLocator implements Locator {
private final Location location;
public StaxLocator(Location location) {
this.location = location;
}
@Override
public String getPublicId() {
return this.location.getPublicId();
}
@Override
public String getSystemId() {
return this.location.getSystemId();
}
@Override
public int getLineNumber() {
return this.location.getLineNumber();
}
@Override
public int getColumnNumber() {
return this.location.getColumnNumber();
}
}
}