org.epics.pvmanager.jca

Class JCATypeAdapter

java.lang.Object

org.epics.pvmanager.jca.JCATypeAdapter

All Implemented Interfaces:

DataSourceTypeAdapter<JCAConnectionPayload,JCAMessagePayload>

public abstract class JCATypeAdapter
extends Object
implements DataSourceTypeAdapter<JCAConnectionPayload,JCAMessagePayload>

Type adapter for JCA data source. Will match a channel based on the value type provided and the array flag. Will match the cache based on the type class.

Author:

carcassi

Constructor Summary

Constructors

Constructor and Description
JCATypeAdapter(Class<?> typeClass, gov.aps.jca.dbr.DBRType epicsValueType, gov.aps.jca.dbr.DBRType epicsMetaType, Boolean array) Creates a new type adapter.

Method Summary

Methods

Modifier and Type	Method and Description
abstract Object	createValue(gov.aps.jca.dbr.DBR value, gov.aps.jca.dbr.DBR metadata, JCAConnectionPayload connPayload) Given the value and the (optional) metadata, will create the new value.
Object	getSubscriptionParameter(ValueCache cache, JCAConnectionPayload connPayload) The parameters required to open a monitor for the channel.
int	match(ValueCache<?> cache, JCAConnectionPayload connPayload) Determines whether the converter can take values from the channel described by the connection payload and transform them in a type required by the cache.
boolean	updateCache(ValueCache cache, JCAConnectionPayload connPayload, JCAMessagePayload message) Takes the information in the message and updates the cache.

Methods inherited from class java.lang.Object

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

Constructor Detail

JCATypeAdapter

public JCATypeAdapter(Class<?> typeClass,
              gov.aps.jca.dbr.DBRType epicsValueType,
              gov.aps.jca.dbr.DBRType epicsMetaType,
              Boolean array)

Creates a new type adapter.

Parameters:

typeClass - the java type this adapter will create

epicsValueType - the epics type used for the monitor

epicsMetaType - the epics type for the get at connection time; null if no metadata is needed

array - true whether this will require an array type

Method Detail

match

public int match(ValueCache<?> cache,
        JCAConnectionPayload connPayload)

Description copied from interface: DataSourceTypeAdapter

Determines whether the converter can take values from the channel described by the connection payload and transform them in a type required by the cache.

Specified by:

match in interface DataSourceTypeAdapter<JCAConnectionPayload,JCAMessagePayload>

Parameters:

cache - the cache where data will need to be written

connPayload - the connection information

Returns:

zero if there is no match, or the position of the type matched

getSubscriptionParameter

public Object getSubscriptionParameter(ValueCache cache,
                              JCAConnectionPayload connPayload)

Description copied from interface: DataSourceTypeAdapter

The parameters required to open a monitor for the channel. The type of the parameters will be datasource specific

For channels multiplexed on a single subscription, this method is never used.

Specified by:

getSubscriptionParameter in interface DataSourceTypeAdapter<JCAConnectionPayload,JCAMessagePayload>

Parameters:

cache - the cache where data will need to be written

connPayload - the connection information

Returns:

datasource specific subscription information

updateCache

public boolean updateCache(ValueCache cache,
                  JCAConnectionPayload connPayload,
                  JCAMessagePayload message)

Description copied from interface: DataSourceTypeAdapter

Takes the information in the message and updates the cache.

Specified by:

updateCache in interface DataSourceTypeAdapter<JCAConnectionPayload,JCAMessagePayload>

Parameters:

cache - cache to be updated

connPayload - the connection information

message - the payload of each message

Returns:

true if a new value was stored

createValue

public abstract Object createValue(gov.aps.jca.dbr.DBR value,
                 gov.aps.jca.dbr.DBR metadata,
                 JCAConnectionPayload connPayload)

Given the value and the (optional) metadata, will create the new value.

Parameters:

value - the value taken from the monitor

metadata - the value taken as metadata

connPayload - the connection payload

Returns:

the new value