SCard Chilkat2 Java Reference Documentation
SCard
Current Version: 11.7.0
Markdown version of this page for AI tools (v 11.7.0) · all AI docs
Chilkat.SCard
Enumerate available PC/SC smart card readers and identify the reader the
application should use.
Connect to a reader/card, check card presence and status, and manage the
active PC/SC connection.
Send APDU commands directly to the card and receive the raw response
bytes and status words.
Issue lower-level reader control commands when supported by the reader
driver and PC/SC environment.
Monitor reader or card status changes so applications can detect card
insertion, removal, or state changes.
Use PC/SC transactions for coordinated card access and inspect detailed
error information when reader or card operations fail.
For an extended overview, see
SCard Class Overview.
Communicate directly with smart card readers and cards through PC/SC.
Chilkat.SCard is the low-level PC/SC smart card interface for
applications that need direct reader and card communication. It supports
reader discovery, reader connection, card status checking, APDU transmission,
reader-control commands, status-change monitoring, transactions, and
diagnostic access to underlying PC/SC errors. Use this class when the
application needs APDU-level control rather than a higher-level certificate,
minidriver, or PKCS#11 abstraction.
Reader discovery
Connect to cards
Transmit APDUs
Reader-control commands
Status monitoring
Transactions and diagnostics
Chilkat.SCard for direct PC/SC
reader and APDU-level work; use Chilkat.ScMinidriver for
card-minidriver certificate and key-container operations, and
Chilkat.Pkcs11 for PKCS#11 token or HSM sessions.
Object Creation
import com.chilkatsoft.chilkat2.ChilkatException;
import com.chilkatsoft.chilkat2.SCard;
try (SCard sCard = new SCard()) {
// ... use sCard ...
} catch (ChilkatException e) {
System.out.println(e.getMessage()); // "SCard.someMethod failed: <reason>"
System.out.println(e.getLastErrorText()); // the full log of the failed call
}Creates the underlying native Chilkat object. The native library (chilkat2java) is loaded the first time any Chilkat2 object is created; see the README in the download for where it is looked for (-Dchilkat2.library.path, a classpath resource, or java.library.path).
Releases the native object (SCard is AutoCloseable, so try-with-resources calls it). Calling it again does nothing; any other method or property accessor called afterwards throws IllegalStateException. An object that is never closed is freed by a background cleaner once it becomes unreachable, but the garbage collector does not see native memory, so closing is the normal path. Objects returned by methods are owned by the caller too.
Returns true once close() has been called.
Errors
A method that fails throws ChilkatException, an unchecked exception carrying getClassName(), getMethodName(), getReason() (one line, also in the message) and getLastErrorText() (the full log, captured at the moment of the failure). The object remains usable. Methods that look something up and find nothing return null instead of throwing (each such method says so), and methods that answer a question (hasMember, isUnlocked, ...) return a plain boolean. Property accessors do not throw for Chilkat reasons.
A null string or object argument throws NullPointerException naming the parameter (except where a method documents that null is accepted), and a string containing U+0000 throws IllegalArgumentException.
Use an object from one thread at a time; it may be handed from one thread to another. The one cross-thread operation is setting setAbortCurrent(true) on an object that is busy in another thread (on the classes that have AbortCurrent). Unlocking: call new Global().unlockBundle("...") once at startup.
Properties
ActiveProtocol
String getActiveProtocol()
The name of the active protocol if connected smart card reader, or an empty string if not connected. Possible values are T0, T1, raw, undefined, or if not connected to a reader.
CardAtr
String getCardAtr()
This is the Current ATR of a card in the connected reader.
topConnectedReader
String getConnectedReader()
The name of the currently connected smart card reader, or an empty string if not connected.
topContext
String getContext()
Contains the string user or system if this object has established a context (by calling EstablishContext). Contains the empty string if no context is established.
DebugLogFilePath
String getDebugLogFilePath()
void setDebugLogFilePath(String value)
If set to a file path, this property logs the LastErrorText of each Chilkat method or property call to the specified file. This logging helps identify the context and history of Chilkat calls leading up to any crash or hang, aiding in debugging.
Enabling the VerboseLogging property provides more detailed information. This property is mainly used for debugging rare instances where a Chilkat method call causes a hang or crash, which should generally not happen.
Possible causes of hangs include:
- A timeout property set to 0, indicating an infinite timeout.
- A hang occurring within an event callback in the application code.
- An internal bug in the Chilkat code causing the hang.
LastErrorHtml
String getLastErrorHtml()
Provides HTML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.
topLastErrorText
String getLastErrorText()
Provides plain text information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.
LastErrorXml
String getLastErrorXml()
Provides XML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.
topLastMethodSuccess
boolean getLastMethodSuccess()
void setLastMethodSuccess(boolean value)
Indicates the success or failure of the most recent method call: true means success, false means failure. This property remains unchanged by property setters or getters. This method is present to address challenges in checking for null or Nothing returns in certain programming languages. Note: This property does not apply to methods that return integer values or to boolean-returning methods where the boolean does not indicate success or failure.
PcscLibPath
String getPcscLibPath()
void setPcscLibPath(String value)
For Linux systems only. Specifies the full path of the libpcsclite.so shared lib. This property should only be used if the libpcsclite.so is in a non-standard location or if Chilkat cannot automatically located it.
topReaderStatus
String getReaderStatus()
The current status of the connected reader. Possible values are:
absent- There is no card in the reader.present- There is a card in the reader, but it has not been moved into position for use.swallowed- There is a card in the reader in position for use. The card is not powered.powered- Power is being provided to the card, but the reader driver is unaware of the mode of the card.negotiable- The card has been reset and is awaiting PTS negotiation.specific- The card has been reset and specific communication protocols have been established.
ScardError
String getScardError()
The last error returned by an underlying PC/SC function. Can be one of the following:
SCARD_W_REMOVED_CARD- The smart card has been removed, so that further communication is not possible.SCARD_W_RESET_CARD- The smart card has been reset, so any shared state information is invalid.
...
VerboseLogging
boolean getVerboseLogging()
void setVerboseLogging(boolean value)
If set to true, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. The default value is false. Verbose logging should only be used for debugging. The potentially large quantity of logged information may adversely affect peformance.
Version
String getVersion()
Methods
BeginTransaction
Establishes a temporary exclusive access mode for doing a series of commands in a transaction.
Throws ChilkatException on failure; e.getLastErrorText() (or the object's getLastErrorText()) explains why, and the object remains usable.
CheckStatus
Check the current status of the currently connected reader. Calling this method updates the ReaderStatus, ActiveProtocol, and CardAtr properties. If this method returns false, none of the properties are updated.
Never throws: false is an answer, not a failure.
Connect
Establish a connection to a reader. The reader is the name of a reader returned from ListReaders. The shareMode can be shared, exclusive, or direct. The preferredProtocol can be 0 (valid only if the shareMode = direct), T0, T1, raw, or no_preference. (No preference is effectively T0 or T1.)
If successful, the state of this object instance is that it's connected to the reader.
Never throws: false is an answer, not a failure.
Disconnect
Terminates a connection with a reader. The disposition can be one of the following values:
leave: Do nothing.reset: Reset the card (warm reset).unpower: Power down the card (cold reset).eject: Eject the card.
Throws ChilkatException on failure; e.getLastErrorText() (or the object's getLastErrorText()) explains why, and the object remains usable.
EndTransaction
Ends a previously begun transaction. The disposition is the action to be taken on the reader, and can be leave which is to do nothing, reset, unpower, or eject.
Throws ChilkatException on failure; e.getLastErrorText() (or the object's getLastErrorText()) explains why, and the object remains usable.
EstablishContext
Creates an Application Context to the PC/SC Resource Manager. This must be the first WinSCard function called in a PC/SC application. The scope can be user or system. After calling, this object will have context and all other methods will use the established context. The Context property will hold the value user or system if context was established, or will be empty if no context was established.
Throws ChilkatException on failure; e.getLastErrorText() (or the object's getLastErrorText()) explains why, and the object remains usable.
FindSmartcards
Returns JSON containing information about the smartcards currently inserted into readers.
Throws ChilkatException on failure; e.getLastErrorText() (or the object's getLastErrorText()) explains why, and the object remains usable.
GetAttrib
Get an attribute from the IFD Handler (reader driver).
The attr can be one of the following:
ASYNC_PROTOCOL_TYPESATR_STRINGCHANNEL_IDCHARACTERISTICSCURRENT_BWTCURRENT_CLKCURRENT_CWTCURRENT_DCURRENT_EBC_ENCODINGCURRENT_FCURRENT_IFSCCURRENT_IFSDCURRENT_IO_STATECURRENT_NCURRENT_PROTOCOL_TYPECURRENT_WDEFAULT_CLKDEFAULT_DATA_RATEDEVICE_FRIENDLY_NAMEDEVICE_IN_USEDEVICE_SYSTEM_NAMEDEVICE_UNITESC_AUTHREQUESTESC_CANCELESC_RESETEXTENDED_BWTICC_INTERFACE_STATUSICC_PRESENCEICC_TYPE_PER_ATRMAX_CLKMAX_DATA_RATEMAX_IFSDMAXINPUTPOWER_MGMT_SUPPORTSUPRESS_T1_IFS_REQUESTSYNC_PROTOCOL_TYPESUSER_AUTH_INPUT_DEVICEUSER_TO_CARD_AUTH_DEVICEVENDOR_IFD_SERIAL_NOVENDOR_IFD_TYPEVENDOR_IFD_VERSIONVENDOR_NAME
The attribute data is returned in bd.
Throws ChilkatException on failure; e.getLastErrorText() (or the object's getLastErrorText()) explains why, and the object remains usable.
GetAttribStr
Get a string typed attribute from the IFD Handler (reader driver).
The attr can be one of the following, but should be limited to the particular attributes that return string values.
ASYNC_PROTOCOL_TYPESATR_STRINGCHANNEL_IDCHARACTERISTICSCURRENT_BWTCURRENT_CLKCURRENT_CWTCURRENT_DCURRENT_EBC_ENCODINGCURRENT_FCURRENT_IFSCCURRENT_IFSDCURRENT_IO_STATECURRENT_NCURRENT_PROTOCOL_TYPECURRENT_WDEFAULT_CLKDEFAULT_DATA_RATEDEVICE_FRIENDLY_NAMEDEVICE_IN_USEDEVICE_SYSTEM_NAMEDEVICE_UNITESC_AUTHREQUESTESC_CANCELESC_RESETEXTENDED_BWTICC_INTERFACE_STATUSICC_PRESENCEICC_TYPE_PER_ATRMAX_CLKMAX_DATA_RATEMAX_IFSDMAXINPUTPOWER_MGMT_SUPPORTSUPRESS_T1_IFS_REQUESTSYNC_PROTOCOL_TYPESUSER_AUTH_INPUT_DEVICEUSER_TO_CARD_AUTH_DEVICEVENDOR_IFD_SERIAL_NOVENDOR_IFD_TYPEVENDOR_IFD_VERSIONVENDOR_NAME
Throws ChilkatException on failure; e.getLastErrorText() (or the object's getLastErrorText()) explains why, and the object remains usable.
GetAttribUint
Get an unsigned integer typed attribute from the IFD Handler (reader driver).
The attr can be one of the following, but should be limited to the particular attributes that return unsigned integer values.
ASYNC_PROTOCOL_TYPESATR_STRINGCHANNEL_IDCHARACTERISTICSCURRENT_BWTCURRENT_CLKCURRENT_CWTCURRENT_DCURRENT_EBC_ENCODINGCURRENT_FCURRENT_IFSCCURRENT_IFSDCURRENT_IO_STATECURRENT_NCURRENT_PROTOCOL_TYPECURRENT_WDEFAULT_CLKDEFAULT_DATA_RATEDEVICE_FRIENDLY_NAMEDEVICE_IN_USEDEVICE_SYSTEM_NAMEDEVICE_UNITESC_AUTHREQUESTESC_CANCELESC_RESETEXTENDED_BWTICC_INTERFACE_STATUSICC_PRESENCEICC_TYPE_PER_ATRMAX_CLKMAX_DATA_RATEMAX_IFSDMAXINPUTPOWER_MGMT_SUPPORTSUPRESS_T1_IFS_REQUESTSYNC_PROTOCOL_TYPESUSER_AUTH_INPUT_DEVICEUSER_TO_CARD_AUTH_DEVICEVENDOR_IFD_SERIAL_NOVENDOR_IFD_TYPEVENDOR_IFD_VERSIONVENDOR_NAME
Returns 0xFFFFFFFF on failure.
topGetStatusChange
Blocks execution until the current availability of the cards in a specific set of readers changes.
This function receives a list of reader names in stReaderNames. It then blocks waiting for a change in state to occur for a maximum blocking time of maxWaitMs (in milliseconds) or forever if 0 is used.
Information about the current reader states and which reader(s) changed is returned in json. See the example below for more information.
To wait for a reader event (reader added or removed) you may use the special reader name \\?PnP?\Notification.
To cancel the ongoing call, call Cancel().
The stReaderNames contains the reader names to check. The json is empty on input, and if the call returns success contains information about the state (after the event change) of each reader.
Throws ChilkatException on failure; e.getLastErrorText() (or the object's getLastErrorText()) explains why, and the object remains usable.
GetStatusChangeCancel
Cancels an ongoing GetStatusChange method call. This would be called from a separate thread in your application if GetStatusChange was called synchronously.
Throws ChilkatException on failure; e.getLastErrorText() (or the object's getLastErrorText()) explains why, and the object remains usable.
ListReaderGroups
Returns a list of currently available reader groups on the system. The reader groups are returned in readerGroups.
Throws ChilkatException on failure; e.getLastErrorText() (or the object's getLastErrorText()) explains why, and the object remains usable.
ListReaders
Returns a list of currently available readers on the system.
Throws ChilkatException on failure; e.getLastErrorText() (or the object's getLastErrorText()) explains why, and the object remains usable.
Reconnect
Reestablishes a connection to a reader that was previously connected to using Connect().
In a multi application environment it is possible for an application to reset the card in shared mode. When this occurs any other application trying to access certain commands will be returned the value SCARD_W_RESET_CARD. When this occurs Reconnect() must be called in order to acknowledge that the card was reset and allow it to change its state accordingly.
The shareMode can be shared, exclusive, or direct. The preferredProtocol can be 0 (valid only if the shareMode = direct), T0, T1, raw, or no_preference. (No preference is effectively T0 or T1.) The action is the desired action taken on the card/reader. It can be leave, reset, unpower, or eject.
If successful, the state of this object instance is that it's connected to the reader.
Throws ChilkatException on failure; e.getLastErrorText() (or the object's getLastErrorText()) explains why, and the object remains usable.
ReleaseContext
Destroys a communication context to the PC/SC Resource Manager. This must be the last function called in a PC/SC application.
Throws ChilkatException on failure; e.getLastErrorText() (or the object's getLastErrorText()) explains why, and the object remains usable.
SendControl
Sends a command directly to the IFD Handler (reader driver) to be processed by the reader.
This is useful for creating client side reader drivers for functions like PIN pads, biometrics, or other extensions to the normal smart card reader that are not normally handled by PC/SC.
The command data is sent in bdSend. The response is written to bdRecv.
Throws ChilkatException on failure; e.getLastErrorText() (or the object's getLastErrorText()) explains why, and the object remains usable.
SendControlHex
Sends a command directly to the IFD Handler (reader driver) to be processed by the reader.
This is useful for creating client side reader drivers for functions like PIN pads, biometrics, or other extensions to the normal smart card reader that are not normally handled by PC/SC.
The command data is provided as a hex string in sendData. The response is written to bdRecv.
Throws ChilkatException on failure; e.getLastErrorText() (or the object's getLastErrorText()) explains why, and the object remains usable.
Transmit
Sends an APDU to the smart card contained in the currently connected reader. The protocolName can be T0, T1, or raw. The APDU to be sent is contained in bdSend. The response from the card is contained in bdRecv. The maxRecvLen is the maximum response size (in bytes) willing to be accepted.
Throws ChilkatException on failure; e.getLastErrorText() (or the object's getLastErrorText()) explains why, and the object remains usable.
TransmitHex
Sends an APDU to the smart card contained in the currently connected reader. The protocolName can be T0, T1, or raw. The APDU (in hexadecimal) to be sent is passed in apduHex. The response from the card is contained in bdRecv. The maxRecvLen is the maximum response size (in bytes) willing to be accepted.
Throws ChilkatException on failure; e.getLastErrorText() (or the object's getLastErrorText()) explains why, and the object remains usable.
Events
All Chilkat methods are synchronous: the call returns when the work is done. During a long-running call, SCard reports progress through a ProgressListener, an interface with three methods, each with a default, so you override only what you need:
import com.chilkatsoft.chilkat2.ProgressListener;
sCard.setProgressListener(new ProgressListener() {
@Override public boolean percentDone(int pctDone) {
System.out.println(pctDone + "%");
return false; // return true to abort the method in progress
}
@Override public void progressInfo(String name, String value) {
System.out.println(name + ": " + value);
}
});For a single callback, a lambda is shorter:
sCard.onPercentDone(pct -> { System.out.println(pct + "%"); return false; });Installs listener as the receiver of this object's events, replacing any listener or lambda installed before; null removes it.
Returns the installed listener, or null.
Each installs a listener whose only callback is the given lambda (from java.util.function). Like setProgressListener, each replaces the listener installed before, so to handle more than one event, implement ProgressListener. null removes the listener.
abortCheck is called periodically during long operations; percentDone is called when an operation's completion percentage is known; progressInfo delivers named progress values. Returning true from abortCheck or percentDone aborts the running method, which then throws ChilkatException.
Callbacks run on the thread that called the method, before it returns. Inside a callback, property accessors of the object (such as setAbortCurrent(true)) and other objects may be used, but calling a method of the same object throws IllegalStateException. An exception thrown by a callback aborts the running method and is rethrown from it; the object remains usable.
AbortCheck
boolean abortCheck()
Enables a method call to be aborted by triggering the AbortCheck event at intervals defined by the HeartbeatMs property. If HeartbeatMs is set to its default value of 0, no events will occur. For instance, set HeartbeatMs to 200 to trigger 5 AbortCheck events per second.
Example
import java.util.concurrent.atomic.AtomicBoolean;
final AtomicBoolean stop = new AtomicBoolean(false); // another thread may call stop.set(true)
sCard.onAbortCheck(() -> stop.get());PercentDone
boolean percentDone(int pctDone)
This provides the percentage completion for any method involving network communications or time-consuming processing, assuming the progress can be measured as a percentage. This event is triggered only when it's possible and logical to express the operation's progress as a percentage. The pctDone argument will range from 1 to 100. For methods that finish quickly, the number of PercentDone callbacks may vary, but the final callback will have pctDone equal to 100. For longer operations, callbacks will not exceed one per percentage point (e.g., 1, 2, 3, ..., 98, 99, 100).
The PercentDone callback also acts as an AbortCheck event. For fast methods where PercentDone fires, an AbortCheck event may not trigger since the PercentDone callback already provides an opportunity to abort. For longer operations, where time between PercentDone callbacks is extended, AbortCheck callbacks enable more responsive operation termination.
To abort the operation, set the abort output argument to true. This will cause the method to terminate and return a failure status or corresponding failure value.
Example
sCard.onPercentDone(pct -> {
// pct ranges from 0 to 100.
System.out.println("Percent done: " + pct);
return false; // return true to abort the method in progress
});ProgressInfo
void progressInfo(String name, String value)
This event callback provides tag name/value pairs that detail what occurs during a method call. To discover existing tag names, create code to handle the event, emit the pairs, and review them. Most tag names are self-explanatory.
Note: Some Chilkat methods don't fire any ProgressInfo events.
Example
sCard.onProgressInfo((name, value) -> System.out.println(name + ": " + value));