org.eclipse.kura.driver

Interface PreparedRead

All Superinterfaces:

java.lang.AutoCloseable

@ProviderType
public interface PreparedRead
extends java.lang.AutoCloseable

This interface represents an optimized request that can be performed by a driver. Implementations of this interface are returned by a driver as a result of a call to the Driver.prepareRead(java.util.List) method.

Since:

1.2

See Also:

Driver.prepareRead(java.util.List)

Method Summary

Modifier and Type	Method and Description
java.util.List<ChannelRecord>	execute() Performs the optimized read request described by this PreparedRead instance.
java.util.List<ChannelRecord>	getChannelRecords() Returns the list of channel records associated with this prepared read.

Methods inherited from interface java.lang.AutoCloseable

close

Method Detail

execute

java.util.List<ChannelRecord> execute()
                               throws Driver.ConnectionException,
                                      KuraException

Performs the optimized read request described by this PreparedRead instance. In order to improve efficiency this method can return the same ChannelRecord instances that were supplied as arguments to the Driver.prepareRead(List) call that created this PreparedRead. The returned records should not be modified while a valid (not closed) PreparedRead holds a reference to them, otherwise unpredictable behavior can occur.

Returns:

the result of the request as a list of ChannelRecord instances.

Throws:

KuraException - if the provided PreparedRead is not valid (for example if it has been closed)

Driver.ConnectionException - if the connection to the field device is interrupted

getChannelRecords

java.util.List<ChannelRecord> getChannelRecords()

Returns the list of channel records associated with this prepared read. In order to improve efficiency this method can return the same ChannelRecord instances that were supplied as arguments to the Driver.prepareRead(List) call that created this PreparedRead. The returned records should not be modified while a valid (not closed) PreparedRead holds a reference to them, otherwise unpredictable behavior can occur.

Returns:

The list of channel records associated with this prepared read.