如何使用JSON主体在java中发送post请求

import org.apache.http.HttpEntity;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpPost;
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;

import java.io.IOException;

public class JsonPostRequestExample {
    public static void main(String[] args) {
        // 创建HTTP客户端
        CloseableHttpClient httpClient = HttpClients.createDefault();

        // 创建POST请求对象
        HttpPost httpPost = new HttpPost("http://example.com/api/endpoint");

        // 设置请求头
        httpPost.setHeader("Content-Type", "application/json");

        // 构建JSON主体
        JsonObject jsonBody = new JsonObject();
        jsonBody.addProperty("key1", "value1");
        jsonBody.addProperty("key2", "value2");

        // 将JSON主体转换为字符串
        String jsonBodyString = jsonBody.toString();

        try {
            // 将JSON字符串设置为请求主体
            StringEntity requestEntity = new StringEntity(jsonBodyString);
            httpPost.setEntity(requestEntity);

            // 发送请求并获取响应
            CloseableHttpResponse response = httpClient.execute(httpPost);
            HttpEntity responseEntity = response.getEntity();

            // 处理响应
            if (responseEntity != null) {
                String responseString = EntityUtils.toString(responseEntity);
                System.out.println("Response: " + responseString);
            }

            // 关闭响应和客户端
            response.close();
            httpClient.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}