import java.io.*;
import java.net.*;

/**
 * http GET與POST請(qǐng)求處理
 * java代碼示例
 *
 * Created by IntelliJ IDEA.
 * User: volcano
 * Date: 2019/11/8
 * Time: 19:36
 */
public class Connection {

    /**
     * 處理http get請(qǐng)求
     * @param path
     * @return
     * @throws MalformedURLException
     */
    public static String doGet(String path) {

        URL url = null;
        HttpURLConnection conn = null;
        InputStream inputStream = null;
        BufferedReader br = null;
        String response = "";
        try {
            //通過請(qǐng)求路徑實(shí)例化一個(gè)URL對(duì)象
            url = new URL(path);
            //通過實(shí)例化的URL對(duì)象創(chuàng)建一個(gè)http連接并轉(zhuǎn)換為HttpURLConnection類型
            conn = (HttpURLConnection) url.openConnection();
            //設(shè)置請(qǐng)求方式，這里我設(shè)置為GET方式
            conn.setRequestMethod("GET");
            //因?yàn)镚ET方式是獲取數(shù)據(jù)用的黎棠，所以需要讀取http的響應(yīng)內(nèi)容韭畸，因此connection需要啟用輸入流(doInput的默認(rèn)值為true滓玖，所以實(shí)際上也可以不寫這行代碼)
//        conn.setDoInput(true);
            //因?yàn)镚ET方式?jīng)]有請(qǐng)求體，所以不需要啟用輸出流(doOutput的默認(rèn)值為false虎眨，所以實(shí)際上也可以不寫這行代碼)
//        conn.setDoInput(false);
            //是否啟用緩存蚓曼，默認(rèn)是啟用的踢代，我這里設(shè)置為不啟用
            conn.setUseCaches(false);

            //通過conn，獲取InputStream對(duì)象
            inputStream = conn.getInputStream();
            br = new BufferedReader(new InputStreamReader(inputStream));

            String line = "";
            StringBuffer buffer = new StringBuffer();

            //按行讀取服務(wù)端響應(yīng)的內(nèi)容
            while ((line = br.readLine()) != null){
                buffer.append(line + System.lineSeparator());
            }

            response = buffer.toString();
        }catch (Exception e) {
            e.printStackTrace();
        } finally {
            //關(guān)閉io對(duì)象以及connection對(duì)象
            if (inputStream != null){
                try {
                    inputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (br != null){
                try {
                    br.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (conn != null){
                conn.disconnect();
            }

            //打印到控制臺(tái)戒劫，查看響應(yīng)內(nèi)容
            System.out.println(response);
            return response;
        }
    }

    /**
     * 處理http POST請(qǐng)求
     * @param path
     * @return
     */
    public static String doPost(String path, String body) {

        URL url = null;
        HttpURLConnection conn = null;
        OutputStream outputStream = null;
        BufferedWriter bw = null;
        InputStream inputStream = null;
        BufferedReader br = null;
        String response = "";
        try {
            url = new URL(path);
            conn = (HttpURLConnection) url.openConnection();
            conn.setRequestMethod("POST");
            conn.setDoInput(true);
            conn.setDoOutput(true);
            conn.setUseCaches(false);

            //先向服務(wù)端發(fā)送請(qǐng)求體內(nèi)容
            outputStream = conn.getOutputStream();
            bw = new BufferedWriter(new OutputStreamWriter(outputStream));
            bw.write(body);
            bw.flush();

            //然后再讀取服務(wù)端響應(yīng)內(nèi)容
            inputStream = conn.getInputStream();
            br = new BufferedReader(new InputStreamReader(inputStream));
            String line = "";
            StringBuffer buffer = new StringBuffer();
            while ((line = br.readLine()) != null){
                buffer.append(line);
            }
            response = buffer.toString();
        } catch (Exception e) {
            e.printStackTrace();
        }finally {
            //關(guān)閉io對(duì)象以及connection對(duì)象
            if (inputStream != null){
                try {
                    inputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (br != null){
                try {
                    br.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (outputStream != null){
                try {
                    outputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (bw != null){
                try {
                    bw.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (conn != null){
                conn.disconnect();
            }

            System.out.println(response);
            return response;
        }
    }

    /**
     * 測(cè)試get與post方法
     * @param args
     */
    public static void main(String[] args) {

        String path_get = "http://www.openldap.org/doc/admin24/intro.html#What%20is%20LDAP";
        doGet(path_get);

        //這里的地址可以依據(jù)自己的情況而定哦
        String path_post = "http://localhost:port/login";
        String body = "{\"login\":{\"userName\":\"test\",\"passwd\":\"qq123456\"}}";
        doPost(path_post,body);

    }

}