jdk.dio.spi

Class AbstractDevice<P extends Device<? super P>>

java.lang.Object

jdk.dio.spi.AbstractDevice<P>

Type Parameters:

P - the device type the descriptor is defined for.

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable, java.nio.channels.Channel, Device<P>

public abstract class AbstractDevice<P extends Device<? super P>>
extends java.lang.Object
implements Device<P>

The AbstractDevice class is the base implementation for Device-implementing classes instantiated by DeviceProvider.
This class encapsulates the low-level machinery required to implement platform-wide locking for exclusive access. It also provides methods that allow for retrieving the DeviceDescriptor of Device instances.

Field Summary

Fields inherited from interface jdk.dio.Device

BIG_ENDIAN, LITTLE_ENDIAN, MIXED_ENDIAN

Constructor Summary

Constructors

Constructor and Description
AbstractDevice()

Method Summary

Methods

Modifier and Type	Method and Description
<U extends P> DeviceDescriptor<U>	getDescriptor() Retrieves the identifying and descriptive information of this device device.
void	tryLock(int timeout) Attempts to lock for (platform-wide) exclusive access the underlying device resource.
void	unlock() Releases from (platform-wide) exclusive access the underlying device device resource.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface jdk.dio.Device

close, isOpen

Constructor Detail

AbstractDevice

public AbstractDevice()

Method Detail

tryLock

public void tryLock(int timeout)
             throws UnavailableDeviceException,
                    ClosedDeviceException,
                    java.io.IOException

Attempts to lock for (platform-wide) exclusive access the underlying device resource. This method will block until the designated device resource becomes available for exclusive access or the specified amount of real time has elapsed. A timeout of 0 means to wait forever.

This method returns silently if the underlying device resource is currently acquired for exclusive access.

Specified by:

tryLock in interface Device<P extends Device<? super P>>

Parameters:

timeout - the timeout in milliseconds.

Throws:

java.lang.IllegalArgumentException - if timeout is negative.

UnavailableDeviceException - if this device is not currently available.

ClosedDeviceException - if this device has been closed.

java.io.IOException - if any other I/O error occurred.

unlock

public void unlock()
            throws java.io.IOException

Releases from (platform-wide) exclusive access the underlying device device resource.

This method returns silently if the underlying device resource is not currently acquired for exclusive access or has already been closed.

Specified by:

unlock in interface Device<P extends Device<? super P>>

Throws:

java.io.IOException - if any other I/O error occurred.

getDescriptor

public final <U extends P> DeviceDescriptor<U> getDescriptor()

Retrieves the identifying and descriptive information of this device device.

Specified by:

getDescriptor in interface Device<P extends Device<? super P>>

Type Parameters:

U - this Device type or a subtype of it (allows for subclassing Device types - see UART and ModemUART).

Returns:

the DeviceDescriptor which encapsulates the identifying and descriptive information of this device.