org.springframework.util.xml.StaxUtils 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.List;
import java.util.function.Supplier;
import javax.xml.stream.XMLEventFactory;
import javax.xml.stream.XMLEventReader;
import javax.xml.stream.XMLEventWriter;
import javax.xml.stream.XMLInputFactory;
import javax.xml.stream.XMLResolver;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.XMLStreamReader;
import javax.xml.stream.XMLStreamWriter;
import javax.xml.stream.events.XMLEvent;
import javax.xml.transform.Result;
import javax.xml.transform.Source;
import javax.xml.transform.stax.StAXResult;
import javax.xml.transform.stax.StAXSource;
import org.xml.sax.ContentHandler;
import org.xml.sax.XMLReader;
import org.springframework.lang.Nullable;
import org.springframework.util.StreamUtils;
/**
* Convenience methods for working with the StAX API. Partly historic due to JAXP 1.3
* compatibility; as of Spring 4.0, relying on JAXP 1.4 as included in JDK 1.6 and higher.
*
* In particular, methods for using StAX ({@code javax.xml.stream}) in combination with
* the TrAX API ({@code javax.xml.transform}), and converting StAX readers/writers into SAX
* readers/handlers and vice-versa.
*
* @author Arjen Poutsma
* @author Juergen Hoeller
* @since 3.0
*/
public abstract class StaxUtils {
private static final XMLResolver NO_OP_XML_RESOLVER =
(publicID, systemID, base, ns) -> StreamUtils.emptyInput();
/**
* Create an {@link XMLInputFactory} with Spring's defensive setup,
* i.e. no support for the resolution of DTDs and external entities.
* @return a new defensively initialized input factory instance to use
* @since 5.0
*/
public static XMLInputFactory createDefensiveInputFactory() {
return createDefensiveInputFactory(XMLInputFactory::newInstance);
}
/**
* Variant of {@link #createDefensiveInputFactory()} with a custom instance.
* @param instanceSupplier supplier for the input factory instance
* @return a new defensively initialized input factory instance to use
* @since 5.0.12
*/
public static T createDefensiveInputFactory(Supplier instanceSupplier) {
T inputFactory = instanceSupplier.get();
inputFactory.setProperty(XMLInputFactory.SUPPORT_DTD, false);
inputFactory.setProperty(XMLInputFactory.IS_SUPPORTING_EXTERNAL_ENTITIES, false);
inputFactory.setXMLResolver(NO_OP_XML_RESOLVER);
return inputFactory;
}
/**
* Create a JAXP 1.4 {@link StAXSource} for the given {@link XMLStreamReader}.
* @param streamReader the StAX stream reader
* @return a source wrapping the {@code streamReader}
*/
public static Source createStaxSource(XMLStreamReader streamReader) {
return new StAXSource(streamReader);
}
/**
* Create a JAXP 1.4 {@link StAXSource} for the given {@link XMLEventReader}.
* @param eventReader the StAX event reader
* @return a source wrapping the {@code eventReader}
*/
public static Source createStaxSource(XMLEventReader eventReader) throws XMLStreamException {
return new StAXSource(eventReader);
}
/**
* Create a custom, non-JAXP 1.4 StAX {@link Source} for the given {@link XMLStreamReader}.
* @param streamReader the StAX stream reader
* @return a source wrapping the {@code streamReader}
*/
public static Source createCustomStaxSource(XMLStreamReader streamReader) {
return new StaxSource(streamReader);
}
/**
* Create a custom, non-JAXP 1.4 StAX {@link Source} for the given {@link XMLEventReader}.
* @param eventReader the StAX event reader
* @return a source wrapping the {@code eventReader}
*/
public static Source createCustomStaxSource(XMLEventReader eventReader) {
return new StaxSource(eventReader);
}
/**
* Indicate whether the given {@link Source} is a JAXP 1.4 StAX Source or
* custom StAX Source.
* @return {@code true} if {@code source} is a JAXP 1.4 {@link StAXSource} or
* custom StAX Source; {@code false} otherwise
*/
public static boolean isStaxSource(Source source) {
return (source instanceof StAXSource || source instanceof StaxSource);
}
/**
* Return the {@link XMLStreamReader} for the given StAX Source.
* @param source a JAXP 1.4 {@link StAXSource}
* @return the {@link XMLStreamReader}
* @throws IllegalArgumentException if {@code source} isn't a JAXP 1.4 {@link StAXSource}
* or custom StAX Source
*/
@Nullable
public static XMLStreamReader getXMLStreamReader(Source source) {
if (source instanceof StAXSource) {
return ((StAXSource) source).getXMLStreamReader();
}
else if (source instanceof StaxSource) {
return ((StaxSource) source).getXMLStreamReader();
}
else {
throw new IllegalArgumentException("Source '" + source + "' is neither StaxSource nor StAXSource");
}
}
/**
* Return the {@link XMLEventReader} for the given StAX Source.
* @param source a JAXP 1.4 {@link StAXSource}
* @return the {@link XMLEventReader}
* @throws IllegalArgumentException if {@code source} isn't a JAXP 1.4 {@link StAXSource}
* or custom StAX Source
*/
@Nullable
public static XMLEventReader getXMLEventReader(Source source) {
if (source instanceof StAXSource) {
return ((StAXSource) source).getXMLEventReader();
}
else if (source instanceof StaxSource) {
return ((StaxSource) source).getXMLEventReader();
}
else {
throw new IllegalArgumentException("Source '" + source + "' is neither StaxSource nor StAXSource");
}
}
/**
* Create a JAXP 1.4 {@link StAXResult} for the given {@link XMLStreamWriter}.
* @param streamWriter the StAX stream writer
* @return a result wrapping the {@code streamWriter}
*/
public static Result createStaxResult(XMLStreamWriter streamWriter) {
return new StAXResult(streamWriter);
}
/**
* Create a JAXP 1.4 {@link StAXResult} for the given {@link XMLEventWriter}.
* @param eventWriter the StAX event writer
* @return a result wrapping {@code streamReader}
*/
public static Result createStaxResult(XMLEventWriter eventWriter) {
return new StAXResult(eventWriter);
}
/**
* Create a custom, non-JAXP 1.4 StAX {@link Result} for the given {@link XMLStreamWriter}.
* @param streamWriter the StAX stream writer
* @return a source wrapping the {@code streamWriter}
*/
public static Result createCustomStaxResult(XMLStreamWriter streamWriter) {
return new StaxResult(streamWriter);
}
/**
* Create a custom, non-JAXP 1.4 StAX {@link Result} for the given {@link XMLEventWriter}.
* @param eventWriter the StAX event writer
* @return a source wrapping the {@code eventWriter}
*/
public static Result createCustomStaxResult(XMLEventWriter eventWriter) {
return new StaxResult(eventWriter);
}
/**
* Indicate whether the given {@link Result} is a JAXP 1.4 StAX Result or
* custom StAX Result.
* @return {@code true} if {@code result} is a JAXP 1.4 {@link StAXResult} or
* custom StAX Result; {@code false} otherwise
*/
public static boolean isStaxResult(Result result) {
return (result instanceof StAXResult || result instanceof StaxResult);
}
/**
* Return the {@link XMLStreamWriter} for the given StAX Result.
* @param result a JAXP 1.4 {@link StAXResult}
* @return the {@link XMLStreamReader}
* @throws IllegalArgumentException if {@code source} isn't a JAXP 1.4 {@link StAXResult}
* or custom StAX Result
*/
@Nullable
public static XMLStreamWriter getXMLStreamWriter(Result result) {
if (result instanceof StAXResult) {
return ((StAXResult) result).getXMLStreamWriter();
}
else if (result instanceof StaxResult) {
return ((StaxResult) result).getXMLStreamWriter();
}
else {
throw new IllegalArgumentException("Result '" + result + "' is neither StaxResult nor StAXResult");
}
}
/**
* Return the {@link XMLEventWriter} for the given StAX Result.
* @param result a JAXP 1.4 {@link StAXResult}
* @return the {@link XMLStreamReader}
* @throws IllegalArgumentException if {@code source} isn't a JAXP 1.4 {@link StAXResult}
* or custom StAX Result
*/
@Nullable
public static XMLEventWriter getXMLEventWriter(Result result) {
if (result instanceof StAXResult) {
return ((StAXResult) result).getXMLEventWriter();
}
else if (result instanceof StaxResult) {
return ((StaxResult) result).getXMLEventWriter();
}
else {
throw new IllegalArgumentException("Result '" + result + "' is neither StaxResult nor StAXResult");
}
}
/**
* Create a {@link XMLEventReader} from the given list of {@link XMLEvent}.
* @param events the list of {@link XMLEvent XMLEvents}.
* @return an {@code XMLEventReader} that reads from the given events
* @since 5.0
*/
public static XMLEventReader createXMLEventReader(List events) {
return new ListBasedXMLEventReader(events);
}
/**
* Create a SAX {@link ContentHandler} that writes to the given StAX {@link XMLStreamWriter}.
* @param streamWriter the StAX stream writer
* @return a content handler writing to the {@code streamWriter}
*/
public static ContentHandler createContentHandler(XMLStreamWriter streamWriter) {
return new StaxStreamHandler(streamWriter);
}
/**
* Create a SAX {@link ContentHandler} that writes events to the given StAX {@link XMLEventWriter}.
* @param eventWriter the StAX event writer
* @return a content handler writing to the {@code eventWriter}
*/
public static ContentHandler createContentHandler(XMLEventWriter eventWriter) {
return new StaxEventHandler(eventWriter);
}
/**
* Create a SAX {@link XMLReader} that reads from the given StAX {@link XMLStreamReader}.
* @param streamReader the StAX stream reader
* @return a XMLReader reading from the {@code streamWriter}
*/
public static XMLReader createXMLReader(XMLStreamReader streamReader) {
return new StaxStreamXMLReader(streamReader);
}
/**
* Create a SAX {@link XMLReader} that reads from the given StAX {@link XMLEventReader}.
* @param eventReader the StAX event reader
* @return a XMLReader reading from the {@code eventWriter}
*/
public static XMLReader createXMLReader(XMLEventReader eventReader) {
return new StaxEventXMLReader(eventReader);
}
/**
* Return a {@link XMLStreamReader} that reads from a {@link XMLEventReader}.
* Useful because the StAX {@code XMLInputFactory} allows one to create an
* event reader from a stream reader, but not vice-versa.
* @return a stream reader that reads from an event reader
*/
public static XMLStreamReader createEventStreamReader(XMLEventReader eventReader) throws XMLStreamException {
return new XMLEventStreamReader(eventReader);
}
/**
* Return a {@link XMLStreamWriter} that writes to a {@link XMLEventWriter}.
* @return a stream writer that writes to an event writer
* @since 3.2
*/
public static XMLStreamWriter createEventStreamWriter(XMLEventWriter eventWriter) {
return new XMLEventStreamWriter(eventWriter, XMLEventFactory.newFactory());
}
/**
* Return a {@link XMLStreamWriter} that writes to a {@link XMLEventWriter}.
* @return a stream writer that writes to an event writer
* @since 3.0.5
*/
public static XMLStreamWriter createEventStreamWriter(XMLEventWriter eventWriter, XMLEventFactory eventFactory) {
return new XMLEventStreamWriter(eventWriter, eventFactory);
}
}