public class JackieDataSource
extends org.diirt.datasource.DataSource
Data source providing Channel Access PVs by using the EPICS Jackie library.
This data-source has type adapters for reading values using the usualy types
from the VType
type hierarchy. When writing values, these VTypes are
also accepted, but the simple types (String
s, boxed types of the
primitives or arrays of primitives) are preferred.
The channel names used when creating channels for this data source can be the pure name of the Channel Access channel or it can be the name of the Channel Access channel with an additional options string appended. If such an options string is present, it must represent a valid JSON object and must follow the actual channel name, separated by a single space character. At the moment, two different options are supported:
The longString option specifies how a channel that has a native
data-type of DBR_CHAR
should be treated. If longString
is true, the value is treated as a null-terminated string, resulting
in a VString
being returned where otherwise a VByteArray
would be returned. If false, a DBR_CHAR
is always
treated as a VByteArray
.
If the longString option is not specified, it is automatically determined based on the channel name. If the channel name ends with ".FIELD$", where FIELD is any string that starts with an upper-case letter and consists only of upper-case letters and digits, longString is set to true. Otherwise, it is set to false.
The putCallback option specifies whether a write operation succeeds immediately, or whether the client waits for the server to acknowledge the write operation. By setting putCallback to false, the code creating the channel effectively tells this implementation that it does not really care whether the write was actually successful. This is rather rare and for this reason, the putCallback option is set to true by default.
Examples of valid options strings are:
Constructor and Description |
---|
JackieDataSource(JackieDataSourceConfiguration configuration)
Creates a data source using the specified configuration.
|
Modifier and Type | Method and Description |
---|---|
void |
close() |
protected org.diirt.datasource.ChannelHandler |
createChannel(java.lang.String channelName) |
public JackieDataSource(JackieDataSourceConfiguration configuration)
configuration
- configuration that shall be used by this data source.Copyright © 2017–2018 aquenos GmbH. All rights reserved.