Magisk/src/main/java/com/topjohnwu/magisk/utils/WebService.java

package com.topjohnwu.magisk.utils;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.List;
import java.util.Map;

public class WebService {

    public static String getString(String url) {
        return getString(url, null);
    }

    public static String getString(String url, Map<String, String> header) {
        HttpURLConnection conn = request(url, header);
        if (conn == null) return "";
        return getString(conn);
    }

    public static String getString(HttpURLConnection conn) {
        try {
            StringBuilder builder = new StringBuilder();
            if (conn.getResponseCode() == HttpURLConnection.HTTP_OK) {
                try (BufferedReader br = new BufferedReader(new InputStreamReader(conn.getInputStream()))) {
                    int len;
                    char buf[] = new char[4096];
                    while ((len = br.read(buf)) != -1) {
                        builder.append(buf, 0, len);
                    }
                }
            }
            conn.disconnect();
            return builder.toString();
        } catch (IOException e) {
            e.printStackTrace();
            return "";
        }
    }

    public static HttpURLConnection request(String address, Map<String, String> header) {
        try {
            URL url = new URL(address);

            HttpURLConnection conn = (HttpURLConnection) url.openConnection();
            conn.setReadTimeout(15000);
            conn.setConnectTimeout(15000);

            if (header != null) {
                for (Map.Entry<String, String> entry : header.entrySet()) {
                    conn.setRequestProperty(entry.getKey(), entry.getValue());
                }
            }

            conn.connect();

            if (header != null) {
                header.clear();
                for (Map.Entry<String, List<String>> entry : conn.getHeaderFields().entrySet()) {
                    List<String> l = entry.getValue();
                    header.put(entry.getKey(), l.get(l.size() - 1));
                }
            }

            return conn;
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }
}