httpview.java

j2me Demos for example

/*
 *
 * Copyright (c) 2007, 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:
 *
 *  * Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *  * Redistributions 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 nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package example.http;

import java.io.DataInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

import java.lang.String;

import java.util.Date;
import java.util.Vector;

import javax.microedition.io.*;
import javax.microedition.lcdui.*;
import javax.microedition.midlet.*;


/**
 * An example MIDlet to fetch a page using an HttpConnection.
 * Refer to the startApp, pauseApp, and destroyApp
 * methods so see how it handles each requested transition.
 */
public class HttpView extends MIDlet implements CommandListener, Runnable {
    /** user interface command for indicating Exit request. */
    Command exitCommand = new Command("Exit", Command.EXIT, 2);

    /** user interface command for indicating a page reload request. */
    Command reloadCommand = new Command("Reload", Command.SCREEN, 1);

    /** user interface command to request an HTTP HEAD transaction. */
    Command headCommand = new Command("Head", Command.SCREEN, 1);

    /** user interface command to request an HTTP POST transaction. */
    Command postCommand = new Command("Post", Command.SCREEN, 1);

    /** user interface command to request an HTTP GET transaction. */
    Command getCommand = new Command("Get", Command.SCREEN, 1);

    /** user interface command to cancel the current screen. */
    Command cancelCommand = new Command("Cancel", Command.SCREEN, 1);

    /** user interface command to return back to previous screen. */
    Command backCommand = new Command("Back", Command.BACK, 1);

    /** user interface command to request current HTTP headers. */
    Command headersCommand = new Command("Headers", Command.SCREEN, 1);

    /** user interface command to display current HTTP request headers. */
    Command requestsCommand = new Command("Requests", Command.SCREEN, 1);

    /** user interface command to display errors from current request. */
    Command errorsCommand = new Command("Errors", Command.SCREEN, 1);

    /** user interface command to enter a new URL */
    Command newURLCommand = new Command("New URL", Command.SCREEN, 10);

    /** user interface command to remove the current URL */
    Command removeURLCommand = new Command("Remove", Command.SCREEN, 11);

    /** user interface command to confirm current screen. */
    Command okCommand = new Command("Ok", Command.SCREEN, 1);

    /** user interface command to display help message. */
    Command helpCommand = new Command("Help", Command.HELP, 1);

    /** user interface component containing a list of URLs */
    List urlList;

    /** array of current URLs */
    Vector urls;

    /** user interface alert component. */
    Alert alert;

    /** user interface text box for the contents of the fetched URL. */
    TextBox content;

    /** current display. */
    Display display;

    /** instance of a thread for asynchronous networking and user interface. */
    Thread thread;

    /** current requested url. */
    String url;

    /** current HTTP request type - GET, HEAD, or POST */
    Command requestCommand;

    /** user interface form to hold progress results. */
    Form progressForm;

    /** user interface progress indicator. */
    Gauge progressGauge;

    /** user interface screen for HTTP headers */
    Form headerForm;

    /** form to display request including parsing */
    Form requestForm;

    /** form to display exceptions */
    Form errorsForm;

    /** data entry text box for inputting URLs */
    TextBox urlbox;

    /** initialize the MIDlet with the current display object. */
    public HttpView() {
        display = Display.getDisplay(this);
        setupList();
        alert = new Alert("Warning");
        alert.setTimeout(2000);

        headerForm = new Form("Headers");
        headerForm.addCommand(backCommand);
        headerForm.addCommand(requestsCommand);
        headerForm.setCommandListener(this);

        requestForm = new Form("Request headers");
        requestForm.addCommand(backCommand);
        requestForm.addCommand(errorsCommand);
        requestForm.setCommandListener(this);

        progressForm = new Form("Progress");
        progressForm.addCommand(cancelCommand);
        progressForm.setCommandListener(this);

        progressGauge = new javax.microedition.lcdui.Gauge(url, false, 9, 0);
        progressForm.append(progressGauge);

        errorsForm = new Form("Errors");
        errorsForm.addCommand(backCommand);
        errorsForm.addCommand(headersCommand);
        errorsForm.setCommandListener(this);

        urlbox = new TextBox("Enter Url", "http://", 400, TextField.URL);
        urlbox.addCommand(okCommand);
        urlbox.setCommandListener(this);
    }

    /**
     * Start creates the thread to do the timing.
     * It should return immediately to keep the dispatcher
     * from hanging.
     */
    public void startApp() {
        /* Bytes read from the URL update connection. */
        int count;

        /* Check for inbound async connection for sample Finger port. */
        String[] connections = PushRegistry.listConnections(true);

        /* HttpView was started to handle inbound request. */
        String pushProperty = getAppProperty("MIDlet-Push-1");

        if ((connections != null) && (connections.length > 0)) {
            String newurl = "Pushed URL Placeholder";

            /* Test basic get registry information interfaces. */
            try {
                String midlet = PushRegistry.getMIDlet(connections[0]);
                String filter = PushRegistry.getFilter(connections[0]);
            } catch (Exception e) {
                e.printStackTrace();
            }

            /* Check for socket or datagram connection. */
            if (connections[0].startsWith("socket://")) {
                try {
                    /* Simple test assumes a server socket connection. */
                    ServerSocketConnection scn =
                        (ServerSocketConnection)Connector.open(connections[0]);
                    SocketConnection sc = (SocketConnection)scn.acceptAndOpen();

                    /* Read one line of text as a new URL to add to the list. */
                    DataInputStream dis = sc.openDataInputStream();
                    byte[] buf = new byte[256];
                    int endofline = 0;
                    count = dis.read(buf);

                    for (int i = 0; i < count; i++) {
                        if (buf[i] == '\n') {
                            endofline = i;

                            break;
                        }
                    }

                    newurl = new String(buf, 0, endofline);

                    dis.close();

                    sc.close();
                    scn.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }

                /*
                 * After successfully receiving a socket posted URL
                 * register a datagram connection, too.
                 */
                try {
                    PushRegistry.registerConnection("datagram://:40080", "example.http.HttpView",
                        "129.148.*.*");
                } catch (ClassNotFoundException e) {
                    e.printStackTrace();
                } catch (IllegalArgumentException e) {
                    e.printStackTrace();
                } catch (ConnectionNotFoundException e) {
                    e.printStackTrace();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            } else if (connections[0].startsWith("datagram://")) {
                /* Must be a datagram connection. */
                try {
                    UDPDatagramConnection udc =
                        (UDPDatagramConnection)Connector.open(connections[0]);
                    Datagram dg = udc.newDatagram(256);

                    udc.receive(dg);
                    udc.close();

                    byte[] buf = dg.getData();

                    int endofline = 0;
                    count = buf.length;

                    for (int i = 0; i < count; i++) {
                        if (buf[i] == '\n') {
                            endofline = i;

                            break;
                        }
                    }

                    newurl = new String(buf, 0, endofline);

                    /* Unregister the datagram connection. */
                    PushRegistry.unregisterConnection("datagram://:40080");
                } catch (SecurityException e) {
                    e.printStackTrace();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            } else {
                //unknown connection type
            }

            urlList.append(newurl, null);
            urls.addElement(newurl);
        } else {
            connections = PushRegistry.listConnections(false);

            /*
             * If the MIDlet was started manually, set an alarm
             * to restart automatically int one minute.
             */
            try {
                Date alarm = new Date();
                PushRegistry.registerAlarm("example.http.HttpView", alarm.getTime() + 60000);
            } catch (ClassNotFoundException e) {
                e.printStackTrace();
            } catch (ConnectionNotFoundException e) {
                e.printStackTrace();
            }
        }

        if (urlList.size() > 0) {
            display.setCurrent(urlList);
        } else {
            alert.setString("No url's configured.");
            display.setCurrent(alert, urlList);
        }
    }

    /**
     * Pause signals the thread to stop by clearing the thread field.
     * If stopped before done with the iterations it will
     * be restarted from scratch later.
     */
    public void pauseApp() {
    }

    /**
     * Destroy must cleanup everything.  The thread is signaled
     * to stop and no result is produced.
     * @param unconditional true if a forced shutdown was requested
     */
    public void destroyApp(boolean unconditional) {
        thread = null;
    }

    /**
     * Check the attributes in the descriptor that identify
     * url's and titles and initialize the lists of urls
     * and urlList.
     * <P>
     * The attributes are named "ViewTitle-n" and "ViewURL-n".
     * The value "n" must start at "1" and increment by 1.
     */
    void setupList() {
        urls = new Vector();
        urlList = new List("URLs", List.IMPLICIT);
        urlList.addCommand(headCommand);
        urlList.addCommand(getCommand);
        urlList.addCommand(postCommand);
        urlList.addCommand(exitCommand);
        urlList.addCommand(newURLCommand);
        urlList.addCommand(removeURLCommand);
        urlList.addCommand(helpCommand);
        urlList.setCommandListener(this);

        for (int n = 1; n < 100; n++) {
            String nthURL = "ViewURL-" + n;
            String url = getAppProperty(nthURL);

            if ((url == null) || (url.length() == 0)) {
                break;
            }

            String nthTitle = "ViewTitle-" + n;
            String title = getAppProperty(nthTitle);

            if ((title == null) || (title.length() == 0)) {
                title = url;
            }

            urls.addElement(url);
            urlList.append(title, null);
        }

        urls.addElement("http://jse.east/Telco/HttpTest.txt");
        // urls.addElement(
        //         "http://dhcp-70-219:8080/examples/servlet/httpdbexport");
        // urls.addElement(
        //       "http://jse.east.sun.com/~kfinn/proxy.jar");
        // urls.addElement(
        //       "http://dhcp-70-219:8080/examples/servlet/HelloWorldKerry");
        urlList.append("Test URL", null);
    }

    /**
     * Respond to commands, including exit
     * @param c user interface command requested
     * @param s screen object initiating the request
     */
    public void commandAction(Command c, Displayable s) {
        try {
            if (c == exitCommand) {
                destroyApp(false);
                notifyDestroyed();
            } else if ((c == headCommand) || (c == getCommand) || (c == postCommand) ||
                    (c == List.SELECT_COMMAND)) {
                if (c == List.SELECT_COMMAND) {
                    c = getCommand;
                }

                requestCommand = c;

                // Display the progress screen and
                // start the thread to read the url
                int i = urlList.getSelectedIndex();

                url = (String)urls.elementAt(i);
                genProgressForm("Progress", url);
                display.setCurrent(progressForm);
                thread = new Thread(this);
                thread.start();
            } else if (c == headersCommand) {
                display.setCurrent(headerForm);
            } else if (c == requestsCommand) {
                display.setCurrent(requestForm);
            } else if (c == errorsCommand) {
                display.setCurrent(errorsForm);
            } else if (c == backCommand) {
                if ((s == headerForm) || (s == requestForm) || (s == errorsForm)) {
                    display.setCurrent(content);
                } else {
                    // Display the list of urls.
                    display.setCurrent(urlList);
                }
            } else if (c == cancelCommand) {
                // Signal thread to stop and put an alert.
                thread = null;
                alert.setString("Loading cancelled.");
                display.setCurrent(alert, urlList);
            } else if (c == newURLCommand) {
                display.setCurrent(urlbox);
            } else if (c == removeURLCommand) {
                int i = urlList.getSelectedIndex();
                urlList.delete(i);
                urls.removeElementAt(i);
            } else if ((c == okCommand) && (s == urlbox)) {
                String newurl = urlbox.getString();
                urlList.append(newurl, null);
                urls.addElement(newurl);
                display.setCurrent(urlList);
            } else if (c == helpCommand) {