MFStandardConnection

[zinxed]

The following code causes classCast exception.

MFStandardConnection conn = null;

public void targetDetected(TargetProperties[] properties)
...

try{

conn = (MFStandardConnection)Connector.open(properties[0].getUrl());

...
}

...

If there is anything that I am doing wrong, then please let me know.

[mariosas]

See you local
C:\Nokia\Devices\Nokia_6131_NFC_SDK_1_1\examples\MFStandardExample\src\com\nokia\nfc\app\mfstdexample

[zinxed]

That example is all about creating a connection with an INTERNAL TAG OF 6131 NFC.

I am trying to build a connection with an external MiFare card....

well...is there anything wrong with my understanding...?

[mariosas]

more information for the assistance.

View the URL to screen to intern and extern?!
What is indicated?
Reads the documentations to the SDK!

java.lang.String getUrl(java.lang.Class connectionName)
Returns the URL for the requested connection to the discovered target.

[zinxed]

Well, the problem is not in getting the right URL.
With the same URL, we are able to establish a NDEFTagConnection but when we typecast the connection to MFStandardConnection, we get classCast exception.

Incase, if MFStandardConnection needs to be established using some other method, then you may help me out.

[mariosas]

See you file.
C:/Nokia/Devices/Nokia_6131_NFC_SDK_1_1/docs/nfc/index.html

Interface TargetProperties
java.lang.String getUrl()
Returns the URL to open a connection to the NDEF_TAG target.

to classCast exception.

java.lang.String getUrl(java.lang.Class connectionName)
Returns the URL for the requested connection to the discovered target.

to no classCast exception.

? OR ?

[HugMarkus]

Hi,
i got the same problem when using MFStandardConnection.
(Class Def not found)
I read hear on the board that i have to update the phone software to version 5.11 to support mifare functionallty.
Now i have updated to this version, but still get this error on the real device.
In the emulator the code works perfectly.

Can anyone help me?

[zinxed]

yes the target type we are trying to listen is : RFID_TAG....

but yet, simpletagconnection or MFstandardConnection casting is causing a problem.

One thing observed as output of the following code:

public void targetDetected(TargetProperties[] properties)
{
//System.out.println(properties[0].getUrl());

Class[] trial = properties[0].getConnectionNames();
System.out.println(properties[0].getUrl(trial[0]));
System.out.println(trial[0].getName()
---- "javax.microedition.contactless.ndef.NDEFTagConnection"

and if you take a look at programmers guide distributed by the 6131 NFC SDK,
one of the section briefing on MFStandardConnection is checking for the string from getName method as "com.nokia.mfstd.MFStandardConnection"

Well, I think this is the problem that we are trying to typecast a NDEFTagConnection to MFStandardConnection...

well..is my analysis of the problem correct? Or the problem is altogether different.

Whatever be the problem, we need a solution for this....

ANybody who has any knowledge regarding the same, may please contribute and hence help us advance to the next stage of development.

Thanks in advance.

Kind Regards.

[mariosas]

!Reads my last entries!

getUrl

java.lang.String getUrl(java.lang.Class connectionName)

Returns the URL for the requested connection to the discovered target. This URL used to open a connection to the target.

Parameters:
connectionName - name of the connection
Returns:
the URL to the target
Throws:
java.lang.NullPointerException - if connectionName is null
java.lang.IllegalArgumentException - if the URL for the given connectionName is not supported or allowed by the target


Still more help?

[phoenix__]

mariosas, Thanks for your input on this thread. I was having the same problem trying to open a connection to an external MiFare card. Passing the class name to the TargetProperties.getURL() method works.

Regards,
-Jeff

[umeshchaand]

Try this out

It works !!


MFStandardConnection conn = null;
String internalUrl = System.getProperty("internal.mf.url");
conn = (MFStandardConnection) Connector.open(internalUrl);

MFBlock block;
byte KAbytes[] = { (byte)0xFF, (byte)0xFF, (byte)0xFF, (byte)0xFF, (byte)0xFF, (byte)0xFF};
MFKey.KeyA KA = new MFKey.KeyA(KAbytes);

block = conn.getBlock(-1); // getBlock(256);

java.lang.IllegalArgumentException: Invalid block index
at com.nokia.mid.impl.isa.io.protocol.external.nfc.MFStandardConnectionImpl.getBlock(+21)
at nokiatest.startApp(+157)
at javax.microedition.midlet.MIDletProxy.startApp(+7)
at com.nokia.mid.impl.isa.ui.MIDletManager.callStartApp(+4)
at com.nokia.mid.impl.isa.ui.MIDletManager.activateMIDlet(+10)
at com.nokia.mid.impl.isa.ui.MIDletManager.run(+15)