CloseableHttpClient发送get带header

CloseableHttpClient是Apache HttpClient库中的一个接口，用于创建可以关闭连接的HTTP客户端。如果你想要通过它发送GET请求并携带自定义Header，你可以按照以下步骤操作：

1. 首先，你需要创建一个`CloseableHttpResponse`对象，这通常会涉及到`HttpGet`和`HttpClient`的配合。

import org.apache.http.HttpEntity;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;

public CloseableHttpResponse sendGetWithHeaders(String url, Map<String, String> headers) {
    CloseableHttpClient httpClient = HttpClients.createDefault();
    try {
        HttpGet request = new HttpGet(url);
        
        // 添加headers到请求中
        for (String key : headers.keySet()) {
            request.setHeader(key, headers.get(key));
        }

        return httpClient.execute(request);
    } catch (Exception e) {
        throw new RuntimeException("Error sending GET request", e);
    }
}

在这个例子中，`Map<String, String>`里的键值对会被添加到`HttpGet`的头信息中。注意，在实际使用后别忘了关闭`CloseableHttpResponse`和`CloseableHttpClient`，以释放资源：

try {
    CloseableHttpResponse response = sendGetWithHeaders(url, headers);
    HttpEntity entity = response.getEntity();
    // ...处理响应内容...
    EntityUtils.consume(entity); // 关闭实体
    response.close(); // 关闭响应
} finally {
    httpClient.close(); // 关闭HttpClient
}