帮我写一个Java方法，传入json和url，将此json发送至这个url

好的，这是一个比较简单的Java方法，可以使用HttpURLConnection来实现：

import java.io.OutputStreamWriter;
import java.net.HttpURLConnection;
import java.net.URL;

public void sendJson(String jsonString, String urlStr) throws Exception {
    URL url = new URL(urlStr);
    HttpURLConnection conn = (HttpURLConnection) url.openConnection();

    conn.setRequestMethod("POST");
    conn.setRequestProperty("Content-Type", "application/json");
    conn.setDoOutput(true);

    OutputStreamWriter writer = new OutputStreamWriter(conn.getOutputStream(), "UTF-8");
    writer.write(jsonString);
    writer.flush();
    writer.close();

    int responseCode = conn.getResponseCode();
    System.out.println("Response Code : " + responseCode);

    conn.disconnect();
}

你只需要传入json字符串和目标url地址即可。