org.springframework.http.converter.xml.AbstractXmlHttpMessageConverter 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
*
* 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.converter.xml;
import java.io.IOException;
import javax.xml.transform.Result;
import javax.xml.transform.Source;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.stream.StreamResult;
import javax.xml.transform.stream.StreamSource;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpInputMessage;
import org.springframework.http.HttpOutputMessage;
import org.springframework.http.MediaType;
import org.springframework.http.converter.AbstractHttpMessageConverter;
import org.springframework.http.converter.HttpMessageConversionException;
import org.springframework.http.converter.HttpMessageNotReadableException;
import org.springframework.http.converter.HttpMessageNotWritableException;
/**
* Abstract base class for {@link org.springframework.http.converter.HttpMessageConverter HttpMessageConverters}
* that convert from/to XML.
*
* By default, subclasses of this converter support {@code text/xml}, {@code application/xml}, and {@code
* application/*-xml}. This can be overridden by setting the {@link #setSupportedMediaTypes(java.util.List)
* supportedMediaTypes} property.
*
* @author Arjen Poutsma
* @author Juergen Hoeller
* @since 3.0
* @param the converted object type
*/
public abstract class AbstractXmlHttpMessageConverter extends AbstractHttpMessageConverter {
private final TransformerFactory transformerFactory = TransformerFactory.newInstance();
/**
* Protected constructor that sets the {@link #setSupportedMediaTypes(java.util.List) supportedMediaTypes}
* to {@code text/xml} and {@code application/xml}, and {@code application/*-xml}.
*/
protected AbstractXmlHttpMessageConverter() {
super(MediaType.APPLICATION_XML, MediaType.TEXT_XML, new MediaType("application", "*+xml"));
}
@Override
public final T readInternal(Class clazz, HttpInputMessage inputMessage)
throws IOException, HttpMessageNotReadableException {
try {
return readFromSource(clazz, inputMessage.getHeaders(), new StreamSource(inputMessage.getBody()));
}
catch (IOException | HttpMessageConversionException ex) {
throw ex;
}
catch (Exception ex) {
throw new HttpMessageNotReadableException("Could not unmarshal to [" + clazz + "]: " + ex.getMessage(),
ex, inputMessage);
}
}
@Override
protected final void writeInternal(T t, HttpOutputMessage outputMessage)
throws IOException, HttpMessageNotWritableException {
try {
writeToResult(t, outputMessage.getHeaders(), new StreamResult(outputMessage.getBody()));
}
catch (IOException | HttpMessageConversionException ex) {
throw ex;
}
catch (Exception ex) {
throw new HttpMessageNotWritableException("Could not marshal [" + t + "]: " + ex.getMessage(), ex);
}
}
/**
* Transforms the given {@code Source} to the {@code Result}.
* @param source the source to transform from
* @param result the result to transform to
* @throws TransformerException in case of transformation errors
*/
protected void transform(Source source, Result result) throws TransformerException {
this.transformerFactory.newTransformer().transform(source, result);
}
/**
* Abstract template method called from {@link #read(Class, HttpInputMessage)}.
* @param clazz the type of object to return
* @param headers the HTTP input headers
* @param source the HTTP input body
* @return the converted object
* @throws Exception in case of I/O or conversion errors
*/
protected abstract T readFromSource(Class clazz, HttpHeaders headers, Source source) throws Exception;
/**
* Abstract template method called from {@link #writeInternal(Object, HttpOutputMessage)}.
* @param t the object to write to the output message
* @param headers the HTTP output headers
* @param result the HTTP output body
* @throws Exception in case of I/O or conversion errors
*/
protected abstract void writeToResult(T t, HttpHeaders headers, Result result) throws Exception;
}