spring AbstractGenericHttpMessageConverter 源码

spring AbstractGenericHttpMessageConverter 代码

文件路径：/spring-web/src/main/java/org/springframework/http/converter/AbstractGenericHttpMessageConverter.java

/*
 * Copyright 2002-2021 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;

import java.io.IOException;
import java.io.OutputStream;
import java.lang.reflect.Type;

import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpOutputMessage;
import org.springframework.http.MediaType;
import org.springframework.http.StreamingHttpOutputMessage;
import org.springframework.lang.Nullable;

/**
 * Abstract base class for most {@link GenericHttpMessageConverter} implementations.
 *
 * @author Sebastien Deleuze
 * @author Juergen Hoeller
 * @since 4.2
 * @param <T> the converted object type
 */
public abstract class AbstractGenericHttpMessageConverter<T> extends AbstractHttpMessageConverter<T>
		implements GenericHttpMessageConverter<T> {

	/**
	 * Construct an {@code AbstractGenericHttpMessageConverter} with no supported media types.
	 * @see #setSupportedMediaTypes
	 */
	protected AbstractGenericHttpMessageConverter() {
	}

	/**
	 * Construct an {@code AbstractGenericHttpMessageConverter} with one supported media type.
	 * @param supportedMediaType the supported media type
	 */
	protected AbstractGenericHttpMessageConverter(MediaType supportedMediaType) {
		super(supportedMediaType);
	}

	/**
	 * Construct an {@code AbstractGenericHttpMessageConverter} with multiple supported media type.
	 * @param supportedMediaTypes the supported media types
	 */
	protected AbstractGenericHttpMessageConverter(MediaType... supportedMediaTypes) {
		super(supportedMediaTypes);
	}


	@Override
	protected boolean supports(Class<?> clazz) {
		return true;
	}

	@Override
	public boolean canRead(Type type, @Nullable Class<?> contextClass, @Nullable MediaType mediaType) {
		return (type instanceof Class<?> clazz ? canRead(clazz, mediaType) : canRead(mediaType));
	}

	@Override
	public boolean canWrite(@Nullable Type type, Class<?> clazz, @Nullable MediaType mediaType) {
		return canWrite(clazz, mediaType);
	}

	/**
	 * This implementation sets the default headers by calling {@link #addDefaultHeaders},
	 * and then calls {@link #writeInternal}.
	 */
	@Override
	public final void write(final T t, @Nullable final Type type, @Nullable MediaType contentType,
			HttpOutputMessage outputMessage) throws IOException, HttpMessageNotWritableException {

		final HttpHeaders headers = outputMessage.getHeaders();
		addDefaultHeaders(headers, t, contentType);

		if (outputMessage instanceof StreamingHttpOutputMessage streamingOutputMessage) {
			streamingOutputMessage.setBody(outputStream -> writeInternal(t, type, new HttpOutputMessage() {
				@Override
				public OutputStream getBody() {
					return outputStream;
				}
				@Override
				public HttpHeaders getHeaders() {
					return headers;
				}
			}));
		}
		else {
			writeInternal(t, type, outputMessage);
			outputMessage.getBody().flush();
		}
	}

	@Override
	protected void writeInternal(T t, HttpOutputMessage outputMessage)
			throws IOException, HttpMessageNotWritableException {

		writeInternal(t, null, outputMessage);
	}

	/**
	 * Abstract template method that writes the actual body. Invoked from {@link #write}.
	 * @param t the object to write to the output message
	 * @param type the type of object to write (may be {@code null})
	 * @param outputMessage the HTTP output message to write to
	 * @throws IOException in case of I/O errors
	 * @throws HttpMessageNotWritableException in case of conversion errors
	 */
	protected abstract void writeInternal(T t, @Nullable Type type, HttpOutputMessage outputMessage)
			throws IOException, HttpMessageNotWritableException;

}

相关信息

spring 源码目录

相关文章

spring AbstractHttpMessageConverter 源码

spring BufferedImageHttpMessageConverter 源码

spring ByteArrayHttpMessageConverter 源码

spring FormHttpMessageConverter 源码

spring GenericHttpMessageConverter 源码

spring HttpMessageConversionException 源码

spring HttpMessageConverter 源码

spring HttpMessageNotReadableException 源码

spring HttpMessageNotWritableException 源码

spring ObjectToStringHttpMessageConverter 源码