使用Java来httprequest.post(url)参数是map集合

如果要发送的参数是Map集合，可以使用Java中的`Map.Entry`来遍历Map集合，并将参数拼接成URL编码的字符串。以下是一个示例代码：

import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLEncoder;
import java.util.Map;

public class HttpPostExample {
    private final String USER_AGENT = "Mozilla/5.0";

    public static void main(String[] args) throws Exception {
        HttpPostExample http = new HttpPostExample();

        // URL和参数
        String url = "http://example.com/api";
        Map<String, String> params = Map.of("param1", "value1", "param2", "value2");

        // 发送POST请求
        String response = http.sendPost(url, params);
        System.out.println(response);
    }

    // 发送POST请求
    private String sendPost(String url, Map<String, String> params) throws Exception {
        URL obj = new URL(url);
        HttpURLConnection con = (HttpURLConnection) obj.openConnection();

        // 添加请求头
        con.setRequestMethod("POST");
        con.setRequestProperty("User-Agent", USER_AGENT);
        con.setRequestProperty("Accept-Language", "en-US,en;q=0.5");

        // 将参数拼接成URL编码的字符串
        StringBuilder urlParameters = new StringBuilder();
        for (Map.Entry<String, String> entry : params.entrySet()) {
            if (urlParameters.length() > 0) {
                urlParameters.append("&");
            }
            urlParameters.append(URLEncoder.encode(entry.getKey(), "UTF-8"));
            urlParameters.append("=");
            urlParameters.append(URLEncoder.encode(entry.getValue(), "UTF-8"));
        }

        // 发送POST请求
        con.setDoOutput(true);
        DataOutputStream wr = new DataOutputStream(con.getOutputStream());
        wr.writeBytes(urlParameters.toString());
        wr.flush();
        wr.close();

        // 获取响应
        BufferedReader in = new BufferedReader(new InputStreamReader(con.getInputStream()));
        String inputLine;
        StringBuffer response = new StringBuffer();

        while ((inputLine = in.readLine()) != null) {
            response.append(inputLine);
        }
        in.close();

        return response.toString();
    }
}

其中，`sendPost`方法接收URL和Map参数，使用`Map.Entry`遍历Map集合，将参数拼接成URL编码的字符串，并发送POST请求。其他部分与前面的示例代码相同。