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HttpTest.javaAPI DocJ2ME MIDP 2.020090Thu Nov 07 12:02:16 GMT 2002example.http

HttpTest

public class HttpTest extends MIDlet implements CommandListener, Runnable
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. Note: if you run this inside POSE using a multi-homed PC (with more than one network connections), POSE doesn't know how to resolve host names not connected to the first network card. To solve this, add a line like this in your c:/WINNT/system32/drivers/etc/hosts file: 204.71.202.160 www.yahoo.com

Fields Summary
private Command
exitCommand
User interface command to exit the current application.
private Command
getCommand
User interface command to issue an HTTP GET request.
private Command
postCommand
User interface command to issue an HTTP POST request.
private Command
headCommand
User interface command to issue an HTTP HEAD request.
private Command
chooseCommand
User interface command to choose a test.
private Command
addCommand
User interface command to Add a new location.
private Command
addSaveCommand
User interface command to save a new location.
private Command
okCommand
User interface command to confirm current operation.
private Command
cancelCommand
User interface command to abort current operation.
private Display
display
The current display object.
private String
url
The url to GET from the network.
private Vector
urls
Array of target locations.
private List
list
User interface list for selection.
private TextBox
addTextBox
Message area for user entered URl.
private Command
currentCommand
Current command to proccess.
private Thread
commandThread
The current command processing thread.
private int
attempt
Current attempt count.
Constructors Summary
public HttpTest()
Initialize the MIDlet with a handle to the current display


               
      
        urls = new Vector();
        urls.addElement("http://www.yahoo.com/");
        urls.addElement("http://www.sun.com/");
        urls.addElement("https://central.sun.net/");
        urls.addElement("https://www.wellsfargo.com");
        urls.addElement("-----------------------");
        urls.addElement("http://jse.east/Telco/HttpTest.txt");
        urls.addElement("http://spiro.eng/");
        urls.addElement("http://spiro.eng:80/");
        urls.addElement("http://localhost:8080/");
        urls.addElement("-----------------------");
        urls.addElement("shttp://host/notsupportedprotocol");
        urls.addElement("http://:8080/missinghost");
        urls.addElement("http://mal\\formed:axyt/url???");
        urls.addElement("http://www.yahoo.com/no/such/page/");
        urls.addElement("http://www.yahoo.com:29999/no/such/port/");
        urls.addElement("http://no.such.site/");
        urls.addElement("http://www.yahoo.com/bad_proxy/");

        url = (String)urls.elementAt(0);
	display = Display.getDisplay(this);
Methods Summary
static final voidDEBUG(java.lang.String s)
Debug output routine.

param
s string to be printed.

        if (true) {
            System.out.println(s);
        }
voidaddScreen()
Add another screen.

        addTextBox = new TextBox("New URL", "http://", 200, 0);
        addTextBox.addCommand(addSaveCommand);
        addTextBox.addCommand(cancelCommand);
        addTextBox.setCommandListener(this);
	display.setCurrent(addTextBox);
voidchooseScreen()
Pick a screen.

        list = new List("Choose URL", Choice.EXCLUSIVE);
        for (int i = 0; i < urls.size(); i++) {
            list.append((String)urls.elementAt(i), null);
        }
        setCommands(list, true);
	display.setCurrent(list);
public voidcommandAction(Command c, Displayable s)
Respond to commands, including exit

param
c command to perform
param
s Screen displayable object

        synchronized (this) {
            if (commandThread != null) {
                // process only one command at a time
                return;
            }

            currentCommand = c;
            commandThread = new Thread(this);
            commandThread.start();
        }
public voiddestroyApp(boolean unconditional)
Destroy must cleanup everything. The thread is signaled to stop and no result is produced.

param
unconditional Flag to indicate that forced shutdown is requested
voidmainScreen()
Display the main screen.

        String s = "URL = " + url +
            ". Press Get or Post to fetch it, or Choose to " +
            "use another URL";
        TextBox t = new TextBox("Http Test", s, s.length(), 0);
        setCommands(t, false);
	display.setCurrent(t);
public voidpauseApp()
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.
private voidreadContents(java.lang.String request)
Read the content of the page. Don't care about the response headers.

param
request type of HTTP request (GET or POST)

	StringBuffer b = new StringBuffer();
        ++ attempt;
        b.append("attempt " + attempt + " content of " 
                 + request + " " + url + "\n");
	HttpConnection c = null;
        OutputStream os = null;
        InputStream is = null;
	TextBox t = null;

	try {
	    long len = -1;
	    int ch = 0;
            long count = 0;
            int rc;

            DEBUG(request + " Page: " + url); 
            c = (HttpConnection)Connector.open(url);
            DEBUG("c= " + c);

            c.setRequestMethod(request);

            c.setRequestProperty("foldedField",
                 "first line\r\n second line\r\n third line");

            if (request == HttpConnection.POST) {
                String m = "Test POST text.";
                DEBUG("Posting: " + m);
                os = c.openOutputStream();
                os.write(m.getBytes());
                os.close();
            }

            rc = c.getResponseCode();
            if (rc != HttpConnection.HTTP_OK) {
                b.append("Response Code: " + c.getResponseCode() + "\n");
                b.append("Response Message: " + c.getResponseMessage() +
                         "\n\n");
            }

	    is = c.openInputStream();

            DEBUG("is = " + is);
            if (c instanceof HttpConnection) {
                len = ((HttpConnection)c).getLength();
            }
            DEBUG("len = " + len);
	    if (len != -1) {
		// Read exactly Content-Length bytes
                DEBUG("Content-Length: " + len);

		for (int i = 0; i < len; i++) {
		    if ((ch = is.read()) != -1) {
			if (ch <= ' ") {
                            ch = ' ";
                        }
			b.append((char) ch);
                        count ++;
                        if (count > 200) {
                            break;
                        }
		    }
                }
	    } else {
                byte data[] = new byte[100];
                int n = is.read(data, 0, data.length);
                for (int i = 0; i < n; i++) {
                    ch = data[i] & 0x000000ff;
		    b.append((char)ch);
		}
	    }
	    try {
                if (is != null) {
                    is.close();
                }
                if (c != null) {
                    c.close();
                }
	    } catch (Exception ce) {
		DEBUG("Error closing connection");
	    }

	    try {
		len = is.available();
		DEBUG("Inputstream failed to throw IOException after close");
	    } catch (IOException io) {
                DEBUG("expected IOException (available())");
                io.printStackTrace();
		// Test to make sure available() is only valid while
		// the connection is still open.,
	    }

	    t = new TextBox("Http Test", b.toString(), b.length(), 0);
            is = null;
            c = null;
	} catch (IOException ex) {
            ex.printStackTrace();
            DEBUG(ex.getClass().toString());
            DEBUG(ex.toString());
	    DEBUG("Exception reading from http");
	    if (c != null) {
		try {
		    String s = null;
                    if (c instanceof HttpConnection) {
                        s = ((HttpConnection)c).getResponseMessage();
                    }
		    DEBUG(s);
		    if (s == null)
			s = "No Response message";
		    t = new TextBox("Http Error", s, s.length(), 0);
		} catch (IOException e) {
		    e.printStackTrace();
		    String s = e.toString();
		    DEBUG(s);
		    if (s == null)
			s = ex.getClass().getName();
		    t = new TextBox("Http Error", s, s.length(), 0);
		}

                try {
                    c.close();
                } catch (IOException ioe) {
                    // do not over throw current exception
                }
	    } else {
		t = new TextBox("Http Error", "Could not open URL", 128, 0);
	    }
	} catch (IllegalArgumentException ille) {
	    // Check if an invalid proxy web server was detected.
	    t  = new TextBox("Illegal Argument",  
                             ille.getMessage(), 128, 0);
	}

        if (is != null) {
	    try {
		is.close();
	    } catch (Exception ce) {; }
        }

        if (c != null) {
	    try {
		c.close();
	    } catch (Exception ce) {; }
        }

        setCommands(t, false);
	display.setCurrent(t);
private voidreadHeaders(java.lang.String request)
Read the header of an HTTP connection. Don't care about the actual data. All response header fields are displayed in a TextBox screen.

param
request type of HTTP request (GET or POST)

        HttpConnection c;
	TextBox t;
	StringBuffer b;

        try {
            try {
                c = (HttpConnection)Connector.open(url);
            } catch (IllegalArgumentException e) {
                String m = e.getMessage();
                t  = new TextBox("Illegal argument",  e.getMessage(), 128, 0);
                setCommands(t, false);
                display.setCurrent(t);
                return;
            } catch (ConnectionNotFoundException e) {
                t  = new TextBox("Error", "Protocol not supported", 128, 0);
                setCommands(t, false);
                display.setCurrent(t);
                return;
            }

            try {
                c.setRequestMethod(request);
	    
                b = new StringBuffer();
                b.append("URL: ");
                b.append(c.getURL());
                b.append("\nProtocol: ");
                b.append(c.getProtocol());
                b.append("\nHost: " + c.getHost());
                b.append("\nFile: " + c.getFile());
                b.append("\nRef: " + c.getRef());
                b.append("\nQuery: ");
                b.append(c.getQuery());
                b.append("\nPort: ");
                b.append(c.getPort());
                b.append("\nMethod: ");
                b.append(c.getRequestMethod());

                // DEBUG: request DEBUG(b) ; 

                if (c instanceof HttpsConnection) {
                    // getSecurityInfo should connect
                    SecurityInfo sslInfo =
                        ((HttpsConnection)c).getSecurityInfo();
                    Certificate cert = sslInfo.getServerCertificate();

                    b.append("\nSecure protocol: ");
                    b.append(sslInfo.getProtocolName());
                    b.append("\nSecure protocol version: ");
                    b.append(sslInfo.getProtocolVersion());
                    b.append("\nCipher suite: ");
                    b.append(sslInfo.getCipherSuite());

                    if (cert == null) {
                        b.append("\nNo server Certficate.");
                    } else {
                        b.append("\nServer certificate \n\t Type: ");
                        b.append(cert.getType());
                        b.append("\n\t Version: ");
                        b.append(cert.getVersion());
                        b.append("\n\t Serial number: ");
                        b.append(cert.getSerialNumber());
                        b.append("\n\t Issuer: ");
                        b.append(cert.getIssuer());
                        b.append("\n\t Subject: ");
                        b.append(cert.getSubject());
                        b.append("\n\t Signature algorithm: ");
                        b.append(cert.getSigAlgName());
                        b.append("\n\t Not valid before: ");
                        b.append(time2str(cert.getNotBefore()));
                        b.append("\n\t Not valid after:  ");
                        b.append(time2str(cert.getNotAfter()));
                    }
                }

                // if not connected getResponseCode should connect
                b.append("\nResponseCode: ");
                b.append(c.getResponseCode());
                b.append("\nResponseMessage:");
                b.append(c.getResponseMessage());
                b.append("\nContentLength: ");
                b.append(c.getLength());
                b.append("\nContentType: ");
                b.append(c.getType());
                b.append("\nContentEncoding: ");
                b.append(c.getEncoding());
                b.append("\nContentExpiration: ");
                b.append(c.getExpiration());
                b.append("\nDate: ");
                b.append(c.getDate());
                b.append("\nLast-Modified: ");
                b.append(c.getLastModified());
                b.append("\n\n");

                // DEBUG: Reply  DEBUG(b) ; 

                int h = 0;
                while (true) {
                    try {
                        String key = c.getHeaderFieldKey(h);
                        if (key == null) {
                            break;
                        }

                        String value = c.getHeaderField(h);
                        b.append(key);
                        b.append(": ");
                        b.append(value);
                        b.append("\n");
                        h++;
                        // DEBUG: DEBUG( key + "(" + h + "): " +
                        //        value) ;
                    }
                    catch (Exception e) {
                        // DEBUG: DEBUG(
                        //     "Exception while fetching headers");
                        break;
                    }
                }

                t = new TextBox("Http Test", b.toString(), b.length(), 0);
                // DEBUG:	    DEBUG (b.toString());

                setCommands(t, false);
                display.setCurrent(t);
            } finally {
                c.close();
            }
	} catch (ConnectionNotFoundException e) {
            t  = new TextBox("Error", "Could not Connect.", 128, 0);
            setCommands(t, false);
            display.setCurrent(t);
            return;
	} catch (CertificateException e) {
            StringBuffer m = new StringBuffer(256);
            String s;
            Certificate cert = e.getCertificate();

            m.append(e.getMessage());
            if (cert != null) {
                m.append("\nServer certificate \n\t Type: ");
                m.append(cert.getType());
                m.append("\n\t Version: ");
                m.append(cert.getVersion());
                m.append("\n\t Serial number: ");
                m.append(cert.getSerialNumber());
                m.append("\n\t Issuer: ");
                m.append(cert.getIssuer());
                m.append("\n\t Subject: ");
                m.append(cert.getSubject());
                m.append("\n\t Signature algorithm: ");
                m.append(cert.getSigAlgName());
                m.append("\n\t Not valid before: ");
                m.append(time2str(cert.getNotBefore()));
                m.append("\n\t Not valid after:  ");
                m.append(time2str(cert.getNotAfter()));
            }

            s = m.toString();
            t  = new TextBox("Certificate Error", s, s.length(), 0);
            setCommands(t, false);
            display.setCurrent(t);
            return;
	} catch (IOException ex) {
            ex.printStackTrace();
	}
public voidrun()
Perform the current command set by the method commandAction.

        if (currentCommand == exitCommand) {
            destroyApp(false);
            notifyDestroyed();
        } else if (currentCommand == getCommand) {
            readContents(HttpConnection.GET);
        } else if (currentCommand == postCommand) {
            readContents(HttpConnection.POST);
        } else if (currentCommand == headCommand) {
            readHeaders(HttpConnection.HEAD);
        } else if (currentCommand == chooseCommand) {
            chooseScreen();
        } else if (currentCommand == okCommand) {
            int i = list.getSelectedIndex();
            if (i >= 0) {
                url = list.getString(i);
            }
                
            mainScreen();
        } else if (currentCommand == addSaveCommand) {
            urls.addElement(addTextBox.getString().trim());
            chooseScreen();
        } else if (currentCommand == addCommand) {
            addScreen();
        } else if (currentCommand == cancelCommand) {
            chooseScreen();
        }

        synchronized (this) {
            // signal that another command can be processed
            commandThread = null;
        }
voidsetCommands(Displayable d, boolean islist)
Set the funtion to perform based on commands selected.

param
d Displaybale object
param
islist flag to indicate list processing

        if (islist) {
            d.addCommand(addCommand);
            d.addCommand(okCommand);
        } else {
            d.addCommand(exitCommand);
            d.addCommand(chooseCommand);
            d.addCommand(getCommand);
            d.addCommand(postCommand);
            d.addCommand(headCommand);
        }
        d.setCommandListener(this);
public voidstartApp()
Start creates the thread to do the timing. It should return immediately to keep the dispatcher from hanging.

	// Use the specified URL is overriden in the descriptor
	String u = getAppProperty("HttpTest-Url");
	if (u != null) {
	    url = u;
	}
	    
	mainScreen();
private java.lang.Stringtime2str(long time)
Converts a time to a string containing the corresponding date.
NOTE: This is here only because the J2ME date class does not implement toString() in any meaningful way.

param
time time to be converted
return
a string representation of the time in the form "dayOfWeek, day mon year hour:min:sec GMT"

        Calendar c = Calendar.getInstance(TimeZone.getTimeZone("GMT"));
        c.setTime(new Date(time));
        return c.toString();