digest auth 如何放入请求头中 httpclient怎么设置请求头

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blueice 2024-04-23 10:40:28

文章标签 java python http tomcat linux 文章分类 架构后端开发

在Apache HTTPClient请求中设置自定义HTTP标头的快速指南。在HttpRequest上，调用setHeader（）方法以将HttpHeaders内容类型设置为JSON。适用于各种版本的HttpClient（4.3之前和之后）。

1.简介

如何将自定义HTTP标头设置为HTTPClient Request 。如果您想学习和更深入，请转到此处的 Apache HTTPClient教程部分。

本文中的所有示例，我们将使用域“ http://www.google.com”创建请求。因为它被视为始终运行。

如何使用RequestBuilder发送POST参数

2.根据要求设置标题– 4.3及更高版本

HttpClient 4.3引入了一种新的构建请求的方式 RequestBuilder 。 RequestBuilder.get（）方法返回请求。要在HttpRequest上设置标头，我们将在构建器上使用setHeader（）方法。

以下示例将标题设置如下。

package com.java.w3schools.blog.HttpClient;

import java.io.IOException;

import org.apache.http.HttpHeaders;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpUriRequest;
import org.apache.http.client.methods.RequestBuilder;
import org.apache.http.impl.client.HttpClients;

public class HttpHeaderSetHeaderExample {

 private static String URI = "http://www.google.com";

 public static void main(String[] args) throws ClientProtocolException, IOException {
  HttpClient client = HttpClients.custom().build();
  HttpUriRequest request = RequestBuilder.get().setUri(URI)
    .setHeader(HttpHeaders.CONTENT_TYPE, "application/json").build();
  client.execute(request);

  System.out.println("Getting the header info from request");
  System.out.println("request header propery name : " + request.getAllHeaders()[0].getName());
  System.out.println("request header propery value : " + request.getAllHeaders()[0].getValue());

 }

}

输出：

Getting the header info from request
request header propery name : Content-Type
request header propery value : application/json

3.根据要求设置标题-4.3之前

它与版本4.3完全不同。在旧版本中，您需要使用HttpGet类创建请求。 HttpGet的对象被视为请求对象。在HttpGet上，我们将调用setHeader（）方法。最后，在HttpClient上调用execute（）方法。

在下面的示例中，我们将许多属性设置为标头的一部分。

package com.java.w3schools.blog.HttpClient;

import java.io.IOException;

import org.apache.http.Header;
import org.apache.http.HttpHeaders;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;

public class HttpHeaderSetHeaderExample4_3Before {

 private static String URI = "http://www.google.com";

 public static void main(String[] args) throws ClientProtocolException, IOException {
  HttpClient client = new DefaultHttpClient();
  HttpGet request = new HttpGet(URI);
  request.setHeader(HttpHeaders.ACCEPT_ENCODING, "gzip, deflate, br");
  request.setHeader(HttpHeaders.ACCEPT_LANGUAGE, "en-US,en;q=0.5");
  request.setHeader(HttpHeaders.ACCEPT, "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8");
  request.setHeader(HttpHeaders.CONNECTION, "keep-alive");
  request.setHeader(HttpHeaders.CACHE_CONTROL, "max-age=0");
  request.setHeader(HttpHeaders.USER_AGENT,
    "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.9; rv:50.0) Gecko/20100101 Firefox/50.0");
  request.setHeader(HttpHeaders.HOST, "http://www.google.com");

  client.execute(request);

  System.out.println("Getting the header info from request before HttpClient 4.3 version.");

  Header[] headers = request.getAllHeaders();

  for (Header header : headers) {
   System.out.println("request header propery : " + header.getName() + " Value : " + header.getValue());

  }

 }

}

输出：

Getting the header info from request before HttpClient 4.3 version.
request header propery : Accept-Encoding Value : gzip, deflate, br
request header propery : Accept-Language Value : en-US,en;q=0.5
request header propery : Accept Value : text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
request header propery : Connection Value : keep-alive
request header propery : Cache-Control Value : max-age=0
request header propery : User-Agent Value : Mozilla/5.0 (Macintosh; Intel Mac OS X 10.9; rv:50.0) Gecko/20100101 Firefox/50.0
request header propery : Host Value : http://www.google.com

4.在客户端上设置默认头

有一个选项可以一次为所有请求设置通用标头。在这种方法中，设置标头信息仅完成一次。

除了在每个请求上设置标头信息之外，我们还可以将其配置为客户端本身的默认标头。

创建HTTPClient时，调用setDefaultHeaders（）方法，该方法采用Header列表并将其设置为每个请求。

当标头对于所有请求都必须相同时（例如自定义应用程序标头），这非常有用。

package com.java.w3schools.blog.HttpClient;

import java.io.IOException;
import java.util.Arrays;
import java.util.List;

import org.apache.http.Header;
import org.apache.http.HttpHeaders;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpUriRequest;
import org.apache.http.client.methods.RequestBuilder;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.message.BasicHeader;
import org.apache.http.params.HttpParams;

public class HttpHeaderSetHeaderExample4_3Before {

 private static String URI = "http://www.google.com";

 public static void main(String[] args) throws ClientProtocolException, IOException {

  Header header1 = new BasicHeader(HttpHeaders.CONTENT_TYPE, "application/json");
  Header header2 = new BasicHeader(HttpHeaders.ACCEPT_ENCODING, "gzip, deflate, br");
  Header header3 = new BasicHeader(HttpHeaders.ACCEPT_LANGUAGE, "en-US,en;q=0.5");
  Header header4 = new BasicHeader(HttpHeaders.ACCEPT,
    "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8");
  Header header5 = new BasicHeader(HttpHeaders.CONNECTION, "keep-alive");
  Header header6 = new BasicHeader(HttpHeaders.CACHE_CONTROL, "max-age=0");
  Header header7 = new BasicHeader(HttpHeaders.USER_AGENT,
    "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.9; rv:50.0) Gecko/20100101 Firefox/50.0");
  Header header8 = new BasicHeader(HttpHeaders.HOST, "http://www.google.com");

  List<Header> headers = Arrays.asList(header1, header2, header3, header4, header5, header6, header7, header8);
  HttpClient client = HttpClients.custom().setDefaultHeaders(headers).build();
  HttpUriRequest request = RequestBuilder.get().setUri(URI).build();
  client.execute(request);

 }

}

如果您想在请求中添加其他标题，则可以使用针对特定请求的setHeader（）方法。

5.例外

如果您尝试访问任何不受支持的操作，例如client.getParams（）。

HttpParams allHeaders = client.getParams();

上面的代码产生以下错误。

Exception in thread "main" java.lang.UnsupportedOperationException
 at org.apache.http.impl.client.InternalHttpClient.getParams(InternalHttpClient.java:211)
 at com.java.w3schools.blog.HttpClient.HttpHeaderSetHeaderExample4_3Before.main(HttpHeaderSetHeaderExample4_3Before.java:40)