org.epics.pvmanager

Interface PVWriter<T>

Type Parameters:

T - type of the write payload

All Known Implementing Classes:

PV

public interface PVWriter<T>

An object representing a writable PV. The write payload is specified by the generic type, and is changed is returned by write(java.lang.Object). Changes in values are notified through the PVWriterListener. Listeners can be registered from any thread. The value can only be accessed on the thread on which the listeners is called.

Author:

carcassi

Method Summary

Methods

Modifier and Type	Method and Description
void	addPVWriterListener(PVWriterListener<? extends T> listener) Adds a listener to the value.
void	close() De-registers all listeners, stops all notifications and closes all connections from the data sources needed by this.
boolean	isClosed() True if no more notifications are going to be sent for this PV.
boolean	isWriteConnected() True if the writer is connected and ready to write.
Exception	lastWriteException() Returns the last exception that was generated by write operations and clears it (subsequent call will return null).
void	removePVWriterListener(PVWriterListener<? extends T> listener) Removes a listener to the value.
void	write(T newValue) Writes a new value.

Method Detail

addPVWriterListener

void addPVWriterListener(PVWriterListener<? extends T> listener)

Adds a listener to the value. This method is thread safe.

Parameters:

listener - a new listener

removePVWriterListener

void removePVWriterListener(PVWriterListener<? extends T> listener)

Removes a listener to the value. This method is thread safe.

Parameters:

listener - the old listener

write

void write(T newValue)

Writes a new value. This method can be synchronous or synchronous depending on how the PV was created.

Parameters:

newValue -

close

void close()

De-registers all listeners, stops all notifications and closes all connections from the data sources needed by this. Once the PV is closed, it can't be re-opened. Subsequent calls to close do not do anything.

isClosed

boolean isClosed()

True if no more notifications are going to be sent for this PV.

Returns:

true if closed

isWriteConnected

boolean isWriteConnected()

True if the writer is connected and ready to write.

False if the channel is not connected, or is connected but can't be written to.

Returns:

true if can write

lastWriteException

Exception lastWriteException()

Returns the last exception that was generated by write operations and clears it (subsequent call will return null).

Returns:

the last generated exception or null