An example MIDlet to invoke a CGI script : Servlet Invoke « J2ME « Java Tutorial

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2. J2ME
3. Servlet Invoke

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import java.io.IOException;
import java.io.InputStream;

import javax.microedition.io.Connector;
import javax.microedition.io.HttpConnection;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.TextBox;
import javax.microedition.midlet.MIDlet;

/**
 * An example MIDlet to invoke a CGI script.
 */

public class FirstMidletServlet extends MIDlet {

  private Display display;

  String url = "http://127.0.0.1/HelloServlet";

  public FirstMidletServlet() {
    display = Display.getDisplay(this);
  }

  /**
   * Initialization. Invoked when we activate the MIDlet.
   */
  public void startApp() {
    try {
      invokeServlet(url);
    } catch (IOException e) {
      System.out.println("IOException " + e);
      e.printStackTrace();
    }
  }

  /**
   * Pause, discontinue ....
   */
  public void pauseApp() {

  }

  /**
   * Destroy must cleanup everything.
   */
  public void destroyApp(boolean unconditional) {
  }

  /**
   * Prepare connection and streams then invoke servlet.
   */

  void invokeServlet(String url) throws IOException {
    HttpConnection c = null;
    InputStream is = null;
    StringBuffer b = new StringBuffer();
    TextBox t = null;
    try {
      c = (HttpConnection) Connector.open(url);
      c.setRequestMethod(HttpConnection.GET);
      c.setRequestProperty("IF-Modified-Since", "20 Jan 2001 16:19:14 GMT");
      c.setRequestProperty("User-Agent",
          "Profile/MIDP-1.0 Configuration/CLDC-1.0");
      c.setRequestProperty("Content-Language", "en-CA");
      is = c.openDataInputStream();
      int ch;
      while ((ch = is.read()) != -1) {
        b.append((char) ch);
        // System.out.println((char)ch);
      }
      t = new TextBox("First Servlet", b.toString(), 1024, 0);
    } finally {
      if (is != null) {
        is.close();
      }
      if (c != null) {
        c.close();
      }
    }
    display.setCurrent(t);
  }
}