java设置httpheaders_HttpClient 请求添加Header头部信息

HTTP消息可以包含许多描述消息属性的标头，例如内容长度，内容类型，授权等。 HttpClient提供了检索，添加，删除和枚举标头的方法。 在下面的教程中，我们将演示如何将自定义HTTP头添加到HttpClient和Http请求方法。

Maven依赖关系

我们使用maven来管理依赖关系，并使用Apache HttpClient 4.5版本。 将以下依赖项添加到您的项目中。

pom.xml 文件的内容如下
 

xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

xsi:schemaLocation="http://maven.apache.org/POM/4.0.0

http://maven.apache.org/xsd/maven-4.0.0.xsd">

4.0.0

com.yiibai.httpclient.httmethods

http-get

1.0.0-SNAPSHOT

https://memorynotfound.com

httpclient - ${project.artifactId}

org.apache.httpcomponents

httpclient

4.5.2

maven-compiler-plugin

3.5.1

1.8

1.8

自定义HTTP头示例

HttpClient允许我们添加，编辑，删除或枚举http头。 首先来看看在HttpClient上设置默认标头。 接下来，我们在消息上添加自定义HTTP请求标头。

文件:HttpClientRedirectHandlingExample.java -

import org.apache.http.Header;

import org.apache.http.HttpEntity;

import org.apache.http.HttpHeaders;

import org.apache.http.client.ClientProtocolException;

import org.apache.http.client.ResponseHandler;

import org.apache.http.client.methods.HttpUriRequest;

import org.apache.http.client.methods.RequestBuilder;

import org.apache.http.impl.client.CloseableHttpClient;

import org.apache.http.impl.client.HttpClients;

import org.apache.http.message.BasicHeader;

import org.apache.http.util.EntityUtils;

import java.io.IOException;

import java.util.Arrays;

import java.util.List;

/**

* This example demonstrates how to use custom http headers.

*/

public class HttpClientCustomHeadersExample {
public static void main(String... args) throws IOException {
// create custom http headers for httpclient

List defaultHeaders = Arrays.asList(

new BasicHeader("X-Default-Header", "default header httpclient"));

// setting custom http headers on the httpclient

CloseableHttpClient httpclient = HttpClients

.custom()

.setDefaultHeaders(defaultHeaders)

.build();

try {
// setting custom http headers on the http request

HttpUriRequest request = RequestBuilder.get()

.setUri("http://httpbin.org/headers")

.setHeader(HttpHeaders.CONTENT_TYPE, "application/json")

.setHeader(HttpHeaders.FROM, "https://memorynotfound.com")

.setHeader("X-Custom-Header", "custom header http request")

.build();

System.out.println("Executing request " + request.getRequestLine());

// Create a custom response handler

ResponseHandler responseHandler = response -> {
int status = response.getStatusLine().getStatusCode();

if (status >= 200 && status 

HttpEntity entity = response.getEntity();

return entity != null ? EntityUtils.toString(entity) : null;

} else {
throw new ClientProtocolException("Unexpected response status: " + status);

}

};

String responseBody = httpclient.execute(request, responseHandler);

System.out.println("----------------------------------------");

System.out.println(responseBody);

} finally {
httpclient.close();

}

}

}

执行上面示例代码，得到以下结果 -

Executing request GET http://httpbin.org/headers HTTP/1.1

----------------------------------------

{
"headers": {
"Accept-Encoding": "gzip,deflate",

"Connection": "close",

"Content-Type": "application/json",

"From": "https://memorynotfound.com",

"Host": "httpbin.org",

"User-Agent": "Apache-HttpClient/4.5.5 (Java/1.8.0_65)",

"X-Custom-Header": "custom header http request",

"X-Default-Header": "default header httpclient"

}

}