GET과 POST 예제프로그램, (URL클래스를 이용한 웹컨텐츠 StreamData 읽기)

GET 방식처리

다음과 같은 방법으로 웹페이지에 접속하여 해당 웹 자원을 읽어낼 수 있다.

import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.net.MalformedURLException; import java.net.URL;   /**  * @author Steven J.S Min  *  */ public class URLStreamDataTest {          /**         * @param args         */        public static void main(String[] args) {                 try {                      URL url = new URL("http://www.naver.com/index.html");                      BufferedReader bin = new BufferedReader(new InputStreamReader(url.openStream()));                        String line;                      while ((line = bin.readLine()) != null) {                            System.out.println(line);                      }                      bin.close();                 } catch (MalformedURLException e) {                      e.printStackTrace();               } catch (IOException e) {                      e.printStackTrace();               }          }   }

 

URLConnection을 통해 Connection를 하면URLConnection의 객체를 통해 부가정보를 얻을 수 있겠다.

  

URL url = new URL("http://www.naver.com/index.html");   URLConnection connection = url.openConnection();   String mimeType = connection.getContentType();   connection.setConnectTimeout(1000); // Timeout 설정 connection.setReadTimeout(10000); // Read Timeout 설정 InputStream in = connection.getInputStream();

 

 

POST 방식처리

다음은 Name필드와 Password 필드를 POST방식으로 전송한는 예이다.

 

import java.awt.Component; import java.awt.GridBagConstraints; import java.awt.GridBagLayout; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.io.IOException; import java.io.OutputStreamWriter; import java.io.PrintWriter; import java.net.HttpURLConnection; import java.net.MalformedURLException; import java.net.URL; import java.net.URLEncoder;   import javax.swing.BorderFactory; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JPanel; import javax.swing.JPasswordField; import javax.swing.JTextField;   public class Post extends JPanel implements ActionListener {        JTextField nameField, passwordField;        String postURL;          GridBagConstraints constraints = new GridBagConstraints();          void addGB(Component component, int x, int y) {               constraints.gridx = x;               constraints.gridy = y;               add(component, constraints);        }          public Post(String postURL) {                 this.postURL = postURL;                 setBorder(BorderFactory.createEmptyBorder(5, 10, 5, 5));               JButton postButton = new JButton("Post");               postButton.addActionListener(this);               setLayout(new GridBagLayout());               constraints.fill = GridBagConstraints.HORIZONTAL;               addGB(new JLabel("Name ", JLabel.TRAILING), 0, 0);               addGB(nameField = new JTextField(20), 1, 0);               addGB(new JLabel("Password ", JLabel.TRAILING), 0, 1);               addGB(passwordField = new JPasswordField(20), 1, 1);               constraints.fill = GridBagConstraints.NONE;               constraints.gridwidth = 2;               constraints.anchor = GridBagConstraints.EAST;               addGB(postButton, 1, 2);        }          public void actionPerformed(ActionEvent e) {               postData();        }          protected void postData() {               StringBuffer sb = new StringBuffer();               sb.append(URLEncoder.encode("Name") + "=");               sb.append(URLEncoder.encode(nameField.getText()));               sb.append("&" + URLEncoder.encode("Password") + "=");               sb.append(URLEncoder.encode(passwordField.getText()));               String formData = sb.toString();                 try {                      URL url = new URL(postURL);                      HttpURLConnection urlcon = (HttpURLConnection) url.openConnection();                      urlcon.setRequestMethod("POST");                      urlcon.setRequestProperty("Content-type", "application/x-www-form-urlencoded");                      urlcon.setDoOutput(true);                      urlcon.setDoInput(true);                      PrintWriter pout =                            new PrintWriter(new OutputStreamWriter(urlcon.getOutputStream(), "8859_1"), true);                      pout.print(formData);                      pout.flush();                        // read results...                      if (urlcon.getResponseCode() != HttpURLConnection.HTTP_OK) System.out.println("Posted ok!");                      else {                            System.out.println("Bad post...");                            return;                      }                      // InputStream in = urlcon.getInputStream( );                      // ...                 } catch (MalformedURLException e) {                      System.out.println(e); // bad postURL               } catch (IOException e2) {                      System.out.println(e2); // I/O error               }        }          public static void main(String[] args) {               JFrame frame = new JFrame("SimplePost");               frame.add(new Post(args[0]), "Center");               frame.pack();               frame.setVisible(true);        } }

실행방법

% java Post http://www.myserver.example/cgi-bin/login.cgi