如何在Apache HttpClient 4.5.13版本中实现GET请求并附带HTTP body（POST数据）？

在Apache HttpClient 4.5.13版本中，GET请求通常不携带HTTP body（POST数据），因为GET用于获取资源，而POST用于提交数据。但是，如果你想模拟一个带数据的GET请求（尽管这在HTTP标准中并不常见），你可以创建一个`HttpGet`对象，并设置它的uri，然后将其与`HttpEntity`结合，如`UrlEncodedFormEntity`。

以下是简单的示例：

import org.apache.http.HttpResponse;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;

public CloseableHttpResponse sendGetWithBody(String baseUrl, Map<String, String> params) throws Exception {
    HttpGet request = new HttpGet(baseUrl);
    
    // 将POST数据编码为URL查询字符串
    StringBuilder urlBuilder = new StringBuilder(baseUrl);
    if (params != null && !params.isEmpty()) {
        urlBuilder.append("?");
        for (Map.Entry<String, String> entry : params.entrySet()) {
            urlBuilder.append(entry.getKey()).append("=").append(URLEncoder.encode(entry.getValue(), "UTF-8")).append("&");
        }
        urlBuilder.setLength(urlBuilder.length() - 1); // 移除最后一个 &
    }
    request.setURI(new URI(urlBuilder.toString()));
    
    // 创建一个StringEntity来包含我们想要发送的数据
    StringEntity entity = new StringEntity(urlBuilder.toString(), ContentType.APPLICATION_FORM_URLENCODED);

    // 设置实体到请求中
    request.setEntity(entity);
    
    CloseableHttpClient httpClient = HttpClients.createDefault();
    try {
        return httpClient.execute(request);
    } finally {
        httpClient.close();
    }
}

// 使用示例
Map<String, String> params = new HashMap<>();
params.put("param1", "value1");
params.put("param2", "value2");
CloseableHttpResponse response = sendGetWithBody("http://example.com/api", params);
try {
    System.out.println(EntityUtils.toString(response.getEntity()));
} finally {
    response.close();
}