Java Java.net.HttpURLConnection用法及代碼示例

// Java Program to Illustrate Use
// of HttpURLConnection Class
// to Retrieve Emotion score of Image
// Using Microsoft Emotion API
// Importing required classes
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import org.json.simple.JSONObject;
// Main class
// httpconclass class
public class GFG {
    // Main driver method
    public static void main(String args[])
        throws IOException
    {
        // Reading input via BufferedReader class
        BufferedReader br = new BufferedReader(
            new InputStreamReader(System.in));
        int n = Integer.parseInt(br.readLine());
        String key = "833921b016964f95905442e0fab0c229";
        JSONObject ezm;
        while (n-- > 0) {
            String image = br.readLine();
            ezm = new JSONObject();
            ezm.put("url", image);
            // Try block to check for exceptions
            try {
                // URL for microsoft cognitive server.
                URL url = new URL(
                    "https://westus.api.cognitive.microsoft.com/emotion/v1.0/recognize");
                HttpURLConnection con
                    = (HttpURLConnection)
                          url.openConnection();
                // Setting the request method and
                // properties.
                con.setRequestMethod("POST");
                con.setRequestProperty(
                    "Ocp-Apim-Subscription-Key", key);
                con.setRequestProperty("Content-Type",
                                       "application/json");
                con.setRequestProperty("Accept",
                                       "application/json");
                // As we know the length of our content,
                // the following function sets the fixed
                // streaming mode length 83 bytes. If
                // content length not known, comment the
                // below line.
                con.setFixedLengthStreamingMode(83);
                // Setting the auto redirection to true
                HttpURLConnection.setFollowRedirects(true);
                // Overriding the default value set by
                // the static method setFollowRedirect above
                con.setInstanceFollowRedirects(false);
                // Setting the doOutput to true for now
                con.setDoOutput(true);
                OutputStream out = con.getOutputStream();
                // System.out.println(ezm.toString().getBytes().length);
                // Writing on the output stream
                out.write(ezm.toString().getBytes());
                InputStream ip = con.getInputStream();
                BufferedReader br1 = new BufferedReader(
                    new InputStreamReader(ip));
                // Printing the response code
                // and response message from server.
                System.out.println("Response Code:"
                                   + con.getResponseCode());
                System.out.println(
                    "Response Message:"
                    + con.getResponseMessage());
                // Note: Uncomment the following line to
                // print the status of FollowRedirect
                // property
                // System.out.println("FollowRedirects:"
                //           +
                //           HttpURLConnection.getFollowRedirects());
                // Printing the status of
                // instanceFollowRedirect property
                System.out.println(
                    "InstanceFollowRedirects:"
                    + con.getInstanceFollowRedirects());
                // Printing the 1st header field
                System.out.println("Header field 1:"
                                   + con.getHeaderField(1));
                // Printing if usingProxy flag set or not
                System.out.println("Using proxy:"
                                   + con.usingProxy());
                StringBuilder response
                    = new StringBuilder();
                String responseSingle = null;
                while ((responseSingle = br1.readLine())
                       != null) {
                    response.append(responseSingle);
                }
                String xx = response.toString();
                System.out.println(xx);
            }
            // Catch block to handle exceptions
            catch (Exception e) {
               
                // Display exception/s on console
                System.out.println(e.getMessage());
            }
        }
    }
}