org.springframework.http.codec.xml.XmlEventDecoder Maven / Gradle / Ivy
/*
* Copyright 2002-2018 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
*
* 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.springframework.http.codec.xml;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.function.Function;
import javax.xml.stream.XMLInputFactory;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.events.XMLEvent;
import javax.xml.stream.util.XMLEventAllocator;
import com.fasterxml.aalto.AsyncByteBufferFeeder;
import com.fasterxml.aalto.AsyncXMLInputFactory;
import com.fasterxml.aalto.AsyncXMLStreamReader;
import com.fasterxml.aalto.evt.EventAllocatorImpl;
import com.fasterxml.aalto.stax.InputFactoryImpl;
import org.reactivestreams.Publisher;
import reactor.core.publisher.Flux;
import reactor.core.publisher.Mono;
import org.springframework.core.ResolvableType;
import org.springframework.core.codec.AbstractDecoder;
import org.springframework.core.io.buffer.DataBuffer;
import org.springframework.core.io.buffer.DataBufferUtils;
import org.springframework.lang.Nullable;
import org.springframework.util.ClassUtils;
import org.springframework.util.MimeType;
import org.springframework.util.MimeTypeUtils;
import org.springframework.util.xml.StaxUtils;
/**
* Decodes a {@link DataBuffer} stream into a stream of {@link XMLEvent XMLEvents}.
*
* Given the following XML:
*
*
* <root>
* <child>foo</child>
* <child>bar</child>
* </root>
*
*
* this decoder will produce a {@link Flux} with the following events:
*
*
* - {@link javax.xml.stream.events.StartDocument}
* - {@link javax.xml.stream.events.StartElement} {@code root}
* - {@link javax.xml.stream.events.StartElement} {@code child}
* - {@link javax.xml.stream.events.Characters} {@code foo}
* - {@link javax.xml.stream.events.EndElement} {@code child}
* - {@link javax.xml.stream.events.StartElement} {@code child}
* - {@link javax.xml.stream.events.Characters} {@code bar}
* - {@link javax.xml.stream.events.EndElement} {@code child}
* - {@link javax.xml.stream.events.EndElement} {@code root}
*
*
* Note that this decoder is not registered by default but is used internally
* by other decoders which are registered by default.
*
* @author Arjen Poutsma
* @since 5.0
*/
public class XmlEventDecoder extends AbstractDecoder {
private static final XMLInputFactory inputFactory = StaxUtils.createDefensiveInputFactory();
private static final boolean aaltoPresent = ClassUtils.isPresent(
"com.fasterxml.aalto.AsyncXMLStreamReader", XmlEventDecoder.class.getClassLoader());
boolean useAalto = aaltoPresent;
public XmlEventDecoder() {
super(MimeTypeUtils.APPLICATION_XML, MimeTypeUtils.TEXT_XML);
}
@Override
@SuppressWarnings({"rawtypes", "unchecked"}) // on JDK 9 where XMLEventReader is Iterator