使用java从url读取json数据。

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.URL;

String urlStr = "https://example.com/data.json";
URL url = new URL(urlStr);

BufferedReader reader = new BufferedReader(new InputStreamReader(url.openStream()));

String line;
StringBuilder jsonStr = new StringBuilder();
while ((line = reader.readLine()) != null) {
    jsonStr.append(line);
}

reader.close();