Many resources are needed to download a project. Please understand that we have to compensate our server costs. Thank you in advance.
Project price only 1 $
You can buy this project and download/modify it how often you want.
org.springframework.http.codec.xml.Jaxb2XmlDecoder Maven / Gradle / Ivy
/*
* Copyright 2002-2020 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.http.codec.xml;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.function.BiConsumer;
import java.util.function.Function;
import javax.xml.XMLConstants;
import javax.xml.bind.JAXBElement;
import javax.xml.bind.JAXBException;
import javax.xml.bind.UnmarshalException;
import javax.xml.bind.Unmarshaller;
import javax.xml.bind.annotation.XmlRootElement;
import javax.xml.bind.annotation.XmlSchema;
import javax.xml.bind.annotation.XmlType;
import javax.xml.namespace.QName;
import javax.xml.stream.XMLEventReader;
import javax.xml.stream.XMLInputFactory;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.events.XMLEvent;
import org.reactivestreams.Publisher;
import reactor.core.Exceptions;
import reactor.core.publisher.Flux;
import reactor.core.publisher.Mono;
import reactor.core.publisher.SynchronousSink;
import org.springframework.core.ResolvableType;
import org.springframework.core.codec.AbstractDecoder;
import org.springframework.core.codec.CodecException;
import org.springframework.core.codec.DecodingException;
import org.springframework.core.codec.Hints;
import org.springframework.core.io.buffer.DataBuffer;
import org.springframework.core.io.buffer.DataBufferLimitException;
import org.springframework.core.io.buffer.DataBufferUtils;
import org.springframework.core.log.LogFormatUtils;
import org.springframework.http.MediaType;
import org.springframework.lang.Nullable;
import org.springframework.util.Assert;
import org.springframework.util.ClassUtils;
import org.springframework.util.MimeType;
import org.springframework.util.MimeTypeUtils;
import org.springframework.util.xml.StaxUtils;
/**
* Decode from a bytes stream containing XML elements to a stream of
* {@code Object}s (POJOs).
*
* @author Sebastien Deleuze
* @author Arjen Poutsma
* @since 5.0
* @see Jaxb2XmlEncoder
*/
public class Jaxb2XmlDecoder extends AbstractDecoder {
/**
* The default value for JAXB annotations.
* @see XmlRootElement#name()
* @see XmlRootElement#namespace()
* @see XmlType#name()
* @see XmlType#namespace()
*/
private static final String JAXB_DEFAULT_ANNOTATION_VALUE = "##default";
private static final XMLInputFactory inputFactory = StaxUtils.createDefensiveInputFactory();
private final XmlEventDecoder xmlEventDecoder = new XmlEventDecoder();
private final JaxbContextContainer jaxbContexts = new JaxbContextContainer();
private Function unmarshallerProcessor = Function.identity();
private int maxInMemorySize = 256 * 1024;
public Jaxb2XmlDecoder() {
super(MimeTypeUtils.APPLICATION_XML, MimeTypeUtils.TEXT_XML, new MediaType("application", "*+xml"));
}
/**
* Create a {@code Jaxb2XmlDecoder} with the specified MIME types.
* @param supportedMimeTypes supported MIME types
* @since 5.1.9
*/
public Jaxb2XmlDecoder(MimeType... supportedMimeTypes) {
super(supportedMimeTypes);
}
/**
* Configure a processor function to customize Unmarshaller instances.
* @param processor the function to use
* @since 5.1.3
*/
public void setUnmarshallerProcessor(Function processor) {
this.unmarshallerProcessor = this.unmarshallerProcessor.andThen(processor);
}
/**
* Return the configured processor for customizing Unmarshaller instances.
* @since 5.1.3
*/
public Function getUnmarshallerProcessor() {
return this.unmarshallerProcessor;
}
/**
* Set the max number of bytes that can be buffered by this decoder.
* This is either the size of the entire input when decoding as a whole, or when
* using async parsing with Aalto XML, it is the size of one top-level XML tree.
* When the limit is exceeded, {@link DataBufferLimitException} is raised.
* By default this is set to 256K.
* @param byteCount the max number of bytes to buffer, or -1 for unlimited
* @since 5.1.11
*/
public void setMaxInMemorySize(int byteCount) {
this.maxInMemorySize = byteCount;
this.xmlEventDecoder.setMaxInMemorySize(byteCount);
}
/**
* Return the {@link #setMaxInMemorySize configured} byte count limit.
* @since 5.1.11
*/
public int getMaxInMemorySize() {
return this.maxInMemorySize;
}
@Override
public boolean canDecode(ResolvableType elementType, @Nullable MimeType mimeType) {
Class outputClass = elementType.toClass();
return (outputClass.isAnnotationPresent(XmlRootElement.class) ||
outputClass.isAnnotationPresent(XmlType.class)) && super.canDecode(elementType, mimeType);
}
@Override
public Flux decode(Publisher inputStream, ResolvableType elementType,
@Nullable MimeType mimeType, @Nullable Map hints) {
Flux xmlEventFlux = this.xmlEventDecoder.decode(
inputStream, ResolvableType.forClass(XMLEvent.class), mimeType, hints);
Class outputClass = elementType.toClass();
QName typeName = toQName(outputClass);
Flux> splitEvents = split(xmlEventFlux, typeName);
return splitEvents.map(events -> {
Object value = unmarshal(events, outputClass);
LogFormatUtils.traceDebug(logger, traceOn -> {
String formatted = LogFormatUtils.formatValue(value, !traceOn);
return Hints.getLogPrefix(hints) + "Decoded [" + formatted + "]";
});
return value;
});
}
@Override
@SuppressWarnings({"rawtypes", "unchecked", "cast"}) // XMLEventReader is Iterator on JDK 9
public Mono decodeToMono(Publisher input, ResolvableType elementType,
@Nullable MimeType mimeType, @Nullable Map hints) {
return DataBufferUtils.join(input, this.maxInMemorySize)
.map(dataBuffer -> decode(dataBuffer, elementType, mimeType, hints));
}
@Override
@SuppressWarnings({"rawtypes", "unchecked", "cast"}) // XMLEventReader is Iterator on JDK 9
public Object decode(DataBuffer dataBuffer, ResolvableType targetType,
@Nullable MimeType mimeType, @Nullable Map hints) throws DecodingException {
try {
Iterator eventReader = inputFactory.createXMLEventReader(dataBuffer.asInputStream());
List events = new ArrayList<>();
eventReader.forEachRemaining(event -> events.add((XMLEvent) event));
return unmarshal(events, targetType.toClass());
}
catch (XMLStreamException ex) {
throw Exceptions.propagate(ex);
}
catch (Throwable ex) {
ex = (ex.getCause() instanceof XMLStreamException ? ex.getCause() : ex);
throw Exceptions.propagate(ex);
}
finally {
DataBufferUtils.release(dataBuffer);
}
}
private Object unmarshal(List events, Class outputClass) {
try {
Unmarshaller unmarshaller = initUnmarshaller(outputClass);
XMLEventReader eventReader = StaxUtils.createXMLEventReader(events);
if (outputClass.isAnnotationPresent(XmlRootElement.class)) {
return unmarshaller.unmarshal(eventReader);
}
else {
JAXBElement jaxbElement = unmarshaller.unmarshal(eventReader, outputClass);
return jaxbElement.getValue();
}
}
catch (UnmarshalException ex) {
throw new DecodingException("Could not unmarshal XML to " + outputClass, ex);
}
catch (JAXBException ex) {
throw new CodecException("Invalid JAXB configuration", ex);
}
}
private Unmarshaller initUnmarshaller(Class outputClass) throws CodecException, JAXBException {
Unmarshaller unmarshaller = this.jaxbContexts.createUnmarshaller(outputClass);
return this.unmarshallerProcessor.apply(unmarshaller);
}
/**
* Returns the qualified name for the given class, according to the mapping rules
* in the JAXB specification.
*/
QName toQName(Class outputClass) {
String localPart;
String namespaceUri;
if (outputClass.isAnnotationPresent(XmlRootElement.class)) {
XmlRootElement annotation = outputClass.getAnnotation(XmlRootElement.class);
localPart = annotation.name();
namespaceUri = annotation.namespace();
}
else if (outputClass.isAnnotationPresent(XmlType.class)) {
XmlType annotation = outputClass.getAnnotation(XmlType.class);
localPart = annotation.name();
namespaceUri = annotation.namespace();
}
else {
throw new IllegalArgumentException("Output class [" + outputClass.getName() +
"] is neither annotated with @XmlRootElement nor @XmlType");
}
if (JAXB_DEFAULT_ANNOTATION_VALUE.equals(localPart)) {
localPart = ClassUtils.getShortNameAsProperty(outputClass);
}
if (JAXB_DEFAULT_ANNOTATION_VALUE.equals(namespaceUri)) {
Package outputClassPackage = outputClass.getPackage();
if (outputClassPackage != null && outputClassPackage.isAnnotationPresent(XmlSchema.class)) {
XmlSchema annotation = outputClassPackage.getAnnotation(XmlSchema.class);
namespaceUri = annotation.namespace();
}
else {
namespaceUri = XMLConstants.NULL_NS_URI;
}
}
return new QName(namespaceUri, localPart);
}
/**
* Split a flux of {@link XMLEvent XMLEvents} into a flux of XMLEvent lists, one list
* for each branch of the tree that starts with the given qualified name.
* That is, given the XMLEvents shown {@linkplain XmlEventDecoder here},
* and the {@code desiredName} "{@code child}", this method returns a flux
* of two lists, each of which containing the events of a particular branch
* of the tree that starts with "{@code child}".
*
* The first list, dealing with the first branch of the tree:
*
* {@link javax.xml.stream.events.StartElement} {@code child}
* {@link javax.xml.stream.events.Characters} {@code foo}
* {@link javax.xml.stream.events.EndElement} {@code child}
*
* The second list, dealing with the second branch of the tree:
*
* {@link javax.xml.stream.events.StartElement} {@code child}
* {@link javax.xml.stream.events.Characters} {@code bar}
* {@link javax.xml.stream.events.EndElement} {@code child}
*
*
*
*/
Flux> split(Flux xmlEventFlux, QName desiredName) {
return xmlEventFlux.handle(new SplitHandler(desiredName));
}
private static class SplitHandler implements BiConsumer>> {
private final QName desiredName;
@Nullable
private List events;
private int elementDepth = 0;
private int barrier = Integer.MAX_VALUE;
public SplitHandler(QName desiredName) {
this.desiredName = desiredName;
}
@Override
public void accept(XMLEvent event, SynchronousSink> sink) {
if (event.isStartElement()) {
if (this.barrier == Integer.MAX_VALUE) {
QName startElementName = event.asStartElement().getName();
if (this.desiredName.equals(startElementName)) {
this.events = new ArrayList<>();
this.barrier = this.elementDepth;
}
}
this.elementDepth++;
}
if (this.elementDepth > this.barrier) {
Assert.state(this.events != null, "No XMLEvent List");
this.events.add(event);
}
if (event.isEndElement()) {
this.elementDepth--;
if (this.elementDepth == this.barrier) {
this.barrier = Integer.MAX_VALUE;
Assert.state(this.events != null, "No XMLEvent List");
sink.next(this.events);
}
}
}
}
}
