| /* |
| * ==================================================================== |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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. |
| * ==================================================================== |
| * |
| * This software consists of voluntary contributions made by many |
| * individuals on behalf of the Apache Software Foundation. For more |
| * information on the Apache Software Foundation, please see |
| * <http://www.apache.org/>. |
| * |
| */ |
| |
| package org.apache.hc.core5.http.protocol; |
| |
| import java.io.IOException; |
| |
| import org.apache.hc.core5.annotation.Contract; |
| import org.apache.hc.core5.annotation.ThreadingBehavior; |
| import org.apache.hc.core5.http.EntityDetails; |
| import org.apache.hc.core5.http.HeaderElements; |
| import org.apache.hc.core5.http.HttpException; |
| import org.apache.hc.core5.http.HttpHeaders; |
| import org.apache.hc.core5.http.HttpResponse; |
| import org.apache.hc.core5.http.HttpResponseInterceptor; |
| import org.apache.hc.core5.http.HttpStatus; |
| import org.apache.hc.core5.http.HttpVersion; |
| import org.apache.hc.core5.http.ProtocolException; |
| import org.apache.hc.core5.http.ProtocolVersion; |
| import org.apache.hc.core5.http.message.MessageSupport; |
| import org.apache.hc.core5.util.Args; |
| |
| /** |
| * ResponseContent is the most important interceptor for outgoing responses. |
| * It is responsible for delimiting content length by adding |
| * {@code Content-Length} or {@code Transfer-Content} headers based |
| * on the properties of the enclosed entity and the protocol version. |
| * This interceptor is required for correct functioning of server side protocol |
| * processors. |
| * |
| * @since 4.0 |
| */ |
| @Contract(threading = ThreadingBehavior.IMMUTABLE) |
| public class ResponseContent implements HttpResponseInterceptor { |
| |
| private final boolean overwrite; |
| |
| /** |
| * Default constructor. The {@code Content-Length} or {@code Transfer-Encoding} |
| * will cause the interceptor to throw {@link ProtocolException} if already present in the |
| * response message. |
| */ |
| public ResponseContent() { |
| this(false); |
| } |
| |
| /** |
| * Constructor that can be used to fine-tune behavior of this interceptor. |
| * |
| * @param overwrite If set to {@code true} the {@code Content-Length} and |
| * {@code Transfer-Encoding} headers will be created or updated if already present. |
| * If set to {@code false} the {@code Content-Length} and |
| * {@code Transfer-Encoding} headers will cause the interceptor to throw |
| * {@link ProtocolException} if already present in the response message. |
| * |
| * @since 4.2 |
| */ |
| public ResponseContent(final boolean overwrite) { |
| super(); |
| this.overwrite = overwrite; |
| } |
| |
| /** |
| * Processes the response (possibly updating or inserting) Content-Length and Transfer-Encoding headers. |
| * @param response The HttpResponse to modify. |
| * @param context Unused. |
| * @throws ProtocolException If either the Content-Length or Transfer-Encoding headers are found. |
| * @throws IllegalArgumentException If the response is null. |
| */ |
| @Override |
| public void process(final HttpResponse response, final EntityDetails entity, final HttpContext context) |
| throws HttpException, IOException { |
| Args.notNull(response, "HTTP response"); |
| if (this.overwrite) { |
| response.removeHeaders(HttpHeaders.TRANSFER_ENCODING); |
| response.removeHeaders(HttpHeaders.CONTENT_LENGTH); |
| } else { |
| if (response.containsHeader(HttpHeaders.TRANSFER_ENCODING)) { |
| throw new ProtocolException("Transfer-encoding header already present"); |
| } |
| if (response.containsHeader(HttpHeaders.CONTENT_LENGTH)) { |
| throw new ProtocolException("Content-Length header already present"); |
| } |
| } |
| final ProtocolVersion ver = context.getProtocolVersion(); |
| if (entity != null) { |
| final long len = entity.getContentLength(); |
| if (len >= 0 && !entity.isChunked()) { |
| response.addHeader(HttpHeaders.CONTENT_LENGTH, Long.toString(entity.getContentLength())); |
| } else if (ver.greaterEquals(HttpVersion.HTTP_1_1)) { |
| response.addHeader(HttpHeaders.TRANSFER_ENCODING, HeaderElements.CHUNKED_ENCODING); |
| MessageSupport.addTrailerHeader(response, entity); |
| } |
| MessageSupport.addContentTypeHeader(response, entity); |
| MessageSupport.addContentEncodingHeader(response, entity); |
| } else { |
| final int status = response.getCode(); |
| if (status != HttpStatus.SC_NO_CONTENT && status != HttpStatus.SC_NOT_MODIFIED) { |
| response.addHeader(HttpHeaders.CONTENT_LENGTH, "0"); |
| } |
| } |
| } |
| |
| } |