Java Tutorial/J2ME/StreamConnection

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/* License
 * 
 * Copyright 1994-2004 Sun Microsystems, Inc. All Rights Reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *  
 *  * Redistribution of source code must retain the above copyright notice,
 *      this list of conditions and the following disclaimer.
 * 
 *  * Redistribution in binary form must reproduce the above copyright notice,
 *      this list of conditions and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 * 
 * Neither the name of Sun Microsystems, Inc. or the names of contributors
 * may be used to endorse or promote products derived from this software
 * without specific prior written permission.
 *  
 * This software is provided "AS IS," without a warranty of any kind. ALL
 * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING
 * ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE
 * OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN MICROSYSTEMS, INC. ("SUN")
 * AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE
 * AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS
 * DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR ANY LOST
 * REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL,
 * INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY
 * OF LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE,
 * EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
 *  
 * You acknowledge that this software is not designed, licensed or intended
 * for use in the design, construction, operation or maintenance of any
 * nuclear facility. 
 */
import java.io.IOException;
import java.io.IOException;
import java.io.InputStream;
import javax.microedition.io.Connector;
import javax.microedition.io.StreamConnection;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.TextBox;
import javax.microedition.midlet.MIDlet;
public class J2MEFirstExample extends MIDlet {
  private Display display;
  String url = "http://www.y.ru/hello.txt";
  public J2MEFirstExample() {
    display = Display.getDisplay(this);
  }
  /**
   * This will be invoked when we start the MIDlet
   */
  public void startApp() {
    try {
      getViaStreamConnection(url);
    } catch (IOException e) {
      e.printStackTrace();
    }
  }
  public void pauseApp() {
  }
  /**
   * Destroy must cleanup everything.
   */
  public void destroyApp(boolean unconditional) {
  }
  /**
   * read url via stream connection
   */
  void getViaStreamConnection(String url) throws IOException {
    StreamConnection c = null;
    InputStream s = null;
    StringBuffer b = new StringBuffer();
    TextBox t = null;
    try {
      c = (StreamConnection) Connector.open(url);
      s = c.openInputStream();
      int ch;
      while ((ch = s.read()) != -1) {
        b.append((char) ch);
      }
      System.out.println(b.toString());
      t = new TextBox("hello....", b.toString(), 1024, 0);
    } finally {
      if (s != null) {
        s.close();
      }
      if (c != null) {
        c.close();
      }
    }
    display.setCurrent(t);
  }
}

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import java.io.IOException;
import java.io.InputStream;
import javax.microedition.io.Connector;
import javax.microedition.io.StreamConnection;
import javax.microedition.lcdui.Alert;
import javax.microedition.lcdui.AlertType;
import javax.microedition.lcdui.rumand;
import javax.microedition.lcdui.rumandListener;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.Form;
import javax.microedition.lcdui.StringItem;
import javax.microedition.midlet.MIDlet;
import javax.microedition.midlet.MIDletStateChangeException;
public class J2MEHttpExample extends MIDlet implements CommandListener {
  private Command exit= new Command("Exit", Command.EXIT, 1), start= new Command("Start", Command.EXIT, 1);
  private Display display;
  private Form form = new Form("Customer Ranking");
  public J2MEHttpExample() {
    display = Display.getDisplay(this);
    form.addCommand(exit);
    form.addCommand(start);
    form.setCommandListener(this);
  }
  public void startApp() throws MIDletStateChangeException {
    display.setCurrent(form);
  }
  public void pauseApp() {
  }
  public void destroyApp(boolean unconditional) {
  }
  public void commandAction(Command command, Displayable displayable) {
    if (command == exit) {
      destroyApp(false);
      notifyDestroyed();
    } else if (command == start) {
      StreamConnection connection = null;
      InputStream in = null;
      StringBuffer buffer = new StringBuffer();
      try {
        connection = (StreamConnection) Connector.open("http://www.a.ru/");
        in = connection.openInputStream();
        int ch;
        while ((ch = in.read()) != -1) {
          if (ch != "\n") {
            buffer.append((char) ch);
          } else {
            String line = new String(buffer.toString());
            if (line.equals("o")) {
              int position = line.indexOf("alt=");
              Alert alert = new Alert("Alert", line.substring(position + 5, position + 8), null,
                  null);
              alert.setTimeout(Alert.FOREVER);
              alert.setType(AlertType.ERROR);
              display.setCurrent(alert);
            }
            buffer = new StringBuffer();
          }
        }
      } catch (IOException error) {
        Alert alert = new Alert("Error", "Cannot connect", null, null);
        alert.setTimeout(Alert.FOREVER);
        alert.setType(AlertType.ERROR);
        display.setCurrent(alert);
      }
    }
  }
}