Instructions

U.are.U SDK - Developer Guide 30
The JAVA API
Working with Readers
Each attached reader is represented with a Reader object. The Reader interface allows:
• Querying reader description and capabilities,
• Acquiring status of the reader,
• Capturing fingerprints,
• Starting and stopping video stream, and
• Resetting and calibrating the reader.
The main methods are:
Capturing Fingerprints
The Capture function captures a fingerprint image for
• Enrollment (as part of the process described on page 12)
• Identifying users with Identify
• Verifying a specific user identity with Compare
The primary fingerprint capture methods are:
Function Description
GetDescription Get the description of a reader. The description is available at any time (even if
the device is not open). This is the only method that can be called before the
open() method.
Returns an object of type
Description holding information about the reader
hardware.
Open Open a device and return the device capabilities. This method establishes an
exclusive link to the device; no other processes will be able to use the device
until you close it. The application must open the device before use.
GetStatus Get the status for a device. You would normally check the device status
between captures to ensure that the device is functioning and there are no error
conditions.
Returns an object of type
ReaderStatus which describes the current status
of the reader.
GetCapabilities Get the capabilities of a device.
Returns an object of type
Capabilities which describes what the reader
can do.
Calibrate Calibrate a device. Some devices are self-calibrating. Ambient light or tempera-
ture can affect calibration, for some devices. Calibration can take several sec-
onds.
Reset Do a hardware reset on the reader. Hardware resets are typically needed only
after a hardware problem (e.g., the device is unplugged or receives an electro-
static shock). Hardware resets typically only take a few milliseconds.
Close Close a reader and release the resources associated with the reader.
Function Description
Capture Captures a fingerprint image from the open reader. This function signals the
reader that a fingerprint is expected, and blocks until a fingerprint is received,
capture fails or the reader times out.