Apache HttpClient基本身份验证示例

Apache HttpClient是一个非常流行的Java HTTP客户端库。它支持基本身份验证（Basic Authentication），该身份验证方案要求用户提供用户名和密码以访问受保护的资源。

以下是一个使用Apache HttpClient进行基本身份验证的示例代码：

import org.apache.http.HttpEntity;
import org.apache.http.HttpHost;
import org.apache.http.auth.AuthScope;
import org.apache.http.auth.UsernamePasswordCredentials;
import org.apache.http.client.CredentialsProvider;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.BasicCredentialsProvider;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;

import java.io.IOException;

public class BasicAuthExample {

    public static void main(String[] args) throws IOException {
        // 创建 HttpClient 实例
        CredentialsProvider credsProvider = new BasicCredentialsProvider();
        credsProvider.setCredentials(
                // 认证范围
                new AuthScope("localhost", 8080),
                // 认证凭据
                new UsernamePasswordCredentials("username", "password"));
        CloseableHttpClient httpclient = HttpClients.custom()
                .setDefaultCredentialsProvider(credsProvider)
                .build();
        try {
            // 创建 HttpGet 请求
            HttpHost target = new HttpHost("localhost", 8080, "http");
            HttpGet httpget = new HttpGet("/");
            System.out.println("Executing request " + httpget.getRequestLine() + " to target " + target);

            // 执行请求
            CloseableHttpResponse response = httpclient.execute(target, httpget);
            try {
                // 获取响应实体
                HttpEntity entity = response.getEntity();
                System.out.println("----------------------------------------");
                System.out.println(response.getStatusLine());
                if (entity != null) {
                    System.out.println("Response content length: " + entity.getContentLength());
                    System.out.println(EntityUtils.toString(entity));
                }
                EntityUtils.consume(entity);
            } finally {
                response.close();
            }
        } finally {
            httpclient.close();
        }
    }
}

在此示例中，我们首先创建了一个 `CredentialsProvider` 对象，该对象包含要用于身份验证的用户名和密码。然后，我们使用 `HttpClients.custom()` 方法创建一个 `CloseableHttpClient` 实例，并将 `CredentialsProvider` 对象设置为默认凭据提供程序。最后，我们执行 HTTP GET 请求并处理响应实体。

请注意，我们需要指定要进行身份验证的范围（即主机名和端口号）。在本例中，我们将其设置为“localhost”和“8080”，但您应该将其替换为适当的值。