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/* * 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.http.converter; import java.io.ByteArrayOutputStream; import java.io.IOException; import org.springframework.http.HttpInputMessage; import org.springframework.http.HttpOutputMessage; import org.springframework.http.MediaType; import org.springframework.lang.Nullable; import org.springframework.util.StreamUtils; /** * Implementation of {@link HttpMessageConverter} that can read and write byte arrays. * * <p>By default, this converter supports all media types (<code>*/*</code>), and * writes with a {@code Content-Type} of {@code application/octet-stream}. This can be * overridden by setting the {@link #setSupportedMediaTypes supportedMediaTypes} property. * * @author Arjen Poutsma * @author Juergen Hoeller * @since 3.0 */ public class ByteArrayHttpMessageConverter extends AbstractHttpMessageConverter<byte[]> { /** * Create a new instance of the {@code ByteArrayHttpMessageConverter}. */ public ByteArrayHttpMessageConverter() { super(MediaType.APPLICATION_OCTET_STREAM, MediaType.ALL); } @Override public boolean supports(Class<?> clazz) { return byte[].class == clazz; } @Override public byte[] readInternal(Class<? extends byte[]> clazz, HttpInputMessage inputMessage) throws IOException { long contentLength = inputMessage.getHeaders().getContentLength(); ByteArrayOutputStream bos = new ByteArrayOutputStream( contentLength >= 0 ? (int) contentLength : StreamUtils.BUFFER_SIZE); StreamUtils.copy(inputMessage.getBody(), bos); return bos.toByteArray(); } @Override protected Long getContentLength(byte[] bytes, @Nullable MediaType contentType) { return (long) bytes.length; } @Override protected void writeInternal(byte[] bytes, HttpOutputMessage outputMessage) throws IOException { StreamUtils.copy(bytes, outputMessage.getBody()); } }