Java 使用 HttpClient 发送 DigestAuth 认证请求

以下是使用 Httpclient 发送 DigestAuth 认证请求的示例代码：

import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

import org.apache.commons.codec.binary.Base64;
import org.apache.http.HttpEntity;
import org.apache.http.HttpHost;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.protocol.HttpClientContext;
import org.apache.http.impl.auth.DigestScheme;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;

public class DigestAuthExample {

    public static void main(String[] args) {

        // 设置代理服务器
        HttpHost proxy = new HttpHost('proxy.example.com', 8080);

        // 设置目标URL
        String url = 'http://example.com/api/data';

        // 设置认证信息
        String username = 'username';
        String password = 'password';
        String realm = 'realm';
        String nonce = 'nonce';
        String qop = 'auth';
        String algorithm = 'MD5';
        String opaque = 'opaque';

        // 创建Httpclient实例
        CloseableHttpClient httpclient = HttpClients.createDefault();

        // 创建HttpGet请求
        HttpGet httpget = new HttpGet(url);

        // 设置代理服务器
        httpget.setConfig(HttpClients.custom().setProxy(proxy).build().getConfig());

        // 设置认证头
        Map<String, String> authHeader = getDigestAuthHeader(httpget, username, password, realm, nonce, qop, algorithm, opaque);
        for (Map.Entry<String, String> entry : authHeader.entrySet()) {
            httpget.setHeader(entry.getKey(), entry.getValue());
        }

        // 创建HttpClient上下文
        HttpClientContext context = HttpClientContext.create();

        try {
            // 执行请求
            CloseableHttpResponse response = httpclient.execute(httpget, context);

            try {
                // 处理响应
                HttpEntity entity = response.getEntity();
                System.out.println(EntityUtils.toString(entity));
                EntityUtils.consume(entity);
            } finally {
                response.close();
            }
        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                httpclient.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

    public static Map<String, String> getDigestAuthHeader(HttpGet httpget, String username, String password, String realm, String nonce, String qop, String algorithm, String opaque) {

        // 创建DigestScheme实例
        DigestScheme digestScheme = new DigestScheme();

        // 设置认证参数
        digestScheme.overrideParamter('username', username);
        digestScheme.overrideParamter('realm', realm);
        digestScheme.overrideParamter('nonce', nonce);
        digestScheme.overrideParamter('uri', httpget.getURI().getPath());
        digestScheme.overrideParamter('qop', qop);
        digestScheme.overrideParamter('nc', '00000001');
        digestScheme.overrideParamter('cnonce', 'cnonce');
        digestScheme.overrideParamter('algorithm', algorithm);
        digestScheme.overrideParamter('opaque', opaque);

        // 计算响应摘要
        String ha1 = DigestScheme.createCnonce();
        String ha2 = DigestScheme.createCnonce();
        String response = digestScheme.calculateResponse(username, password, ha1, ha2);

        // 创建认证头
        Map<String, String> authHeader = new HashMap<String, String>();
        authHeader.put('Authorization', 'Digest ' + digestScheme.getSchemeName() + ' ' +
                'username=' + username + ', ' +
                'realm=' + realm + ', ' +
                'nonce=' + nonce + ', ' +
                'uri=' + httpget.getURI().getPath() + ', ' +
                'qop=' + qop + ', ' +
                'nc=00000001, ' +
                'cnonce=' + digestScheme.getCnonce() + ', ' +
                'response=' + response + ', ' +
                'algorithm=' + algorithm + ', ' +
                'opaque=' + opaque);

        return authHeader;
    }
}

本示例代码展示了如何使用 HttpClient 库发送一个 DigestAuth 认证请求，包括设置代理服务器、目标 URL、认证信息，以及生成和设置认证头。代码中使用了 DigestScheme 类来计算响应摘要，并创建了 Authorization 头。

请注意，代码中的 username, password, realm, nonce, qop, algorithm 和 opaque 是示例值，需要根据实际情况进行修改。

此外，代码中还使用了代理服务器，如果不需要代理，可以将 HttpHost 对象设置为 null。

希望本示例能够帮助你理解如何使用 HttpClient 库发送 DigestAuth 认证请求。