All Downloads are FREE. Search and download functionalities are using the official Maven repository.

org.springframework.web.client.MessageBodyClientHttpResponseWrapper Maven / Gradle / Ivy

There is a newer version: 6.1.13
Show newest version
/*
 * Copyright 2002-2015 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
 *
 *      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.
 */

package org.springframework.web.client;

import java.io.IOException;
import java.io.InputStream;
import java.io.PushbackInputStream;

import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.client.ClientHttpResponse;

/**
 * Implementation of {@link ClientHttpResponse} that can not only check if
 * the response has a message body, but also if its length is 0 (i.e. empty)
 * by actually reading the input stream.
 *
 * @author Brian Clozel
 * @since 4.1.5
 * @see rfc7230 Section 3.3.3
 */
class MessageBodyClientHttpResponseWrapper implements ClientHttpResponse {

	private final ClientHttpResponse response;

	private PushbackInputStream pushbackInputStream;


	public MessageBodyClientHttpResponseWrapper(ClientHttpResponse response) throws IOException {
		this.response = response;
	}


	/**
	 * Indicates whether the response has a message body.
	 * 

Implementation returns {@code false} for: *

    *
  • a response status of {@code 1XX}, {@code 204} or {@code 304}
  • *
  • a {@code Content-Length} header of {@code 0}
  • *
* @return {@code true} if the response has a message body, {@code false} otherwise * @throws IOException in case of I/O errors */ public boolean hasMessageBody() throws IOException { HttpStatus responseStatus = this.getStatusCode(); if (responseStatus.is1xxInformational() || responseStatus == HttpStatus.NO_CONTENT || responseStatus == HttpStatus.NOT_MODIFIED) { return false; } else if (this.getHeaders().getContentLength() == 0) { return false; } return true; } /** * Indicates whether the response has an empty message body. *

Implementation tries to read the first bytes of the response stream: *

    *
  • if no bytes are available, the message body is empty
  • *
  • otherwise it is not empty and the stream is reset to its start for further reading
  • *
* @return {@code true} if the response has a zero-length message body, {@code false} otherwise * @throws IOException in case of I/O errors */ public boolean hasEmptyMessageBody() throws IOException { InputStream body = this.response.getBody(); if (body == null) { return true; } else if (body.markSupported()) { body.mark(1); if (body.read() == -1) { return true; } else { body.reset(); return false; } } else { this.pushbackInputStream = new PushbackInputStream(body); int b = this.pushbackInputStream.read(); if (b == -1) { return true; } else { this.pushbackInputStream.unread(b); return false; } } } @Override public HttpHeaders getHeaders() { return this.response.getHeaders(); } @Override public InputStream getBody() throws IOException { return (this.pushbackInputStream != null ? this.pushbackInputStream : this.response.getBody()); } @Override public HttpStatus getStatusCode() throws IOException { return this.response.getStatusCode(); } @Override public int getRawStatusCode() throws IOException { return this.response.getRawStatusCode(); } @Override public String getStatusText() throws IOException { return this.response.getStatusText(); } @Override public void close() { this.response.close(); } }




© 2015 - 2024 Weber Informatics LLC | Privacy Policy