com.cosylab.epics.caj.cas.util
Class EnumProcessVariable

java.lang.Object
  gov.aps.jca.cas.ProcessVariable
      com.cosylab.epics.caj.cas.util.EnumProcessVariable

public abstract class EnumProcessVariable
extends gov.aps.jca.cas.ProcessVariable

Abstract convenient enumeration process variable implementation.

Field Summary

Fields inherited from class gov.aps.jca.cas.ProcessVariable

ackS, ackT, channelCount, eventCallback, interest, name

Constructor Summary

EnumProcessVariable(String name, gov.aps.jca.cas.ProcessVariableEventCallback eventCallback)
Enum PV constructor.

Method Summary

gov.aps.jca.dbr.DBRType	getType() Return DBRType.ENUM type as native type.
gov.aps.jca.CAStatus	read(gov.aps.jca.dbr.DBR value, gov.aps.jca.cas.ProcessVariableReadCallback asyncReadCallback) Casts DBR to DBR_TIME_LABELS_Enum, sets labels returned by getEnumLabels() and delegates operation of reading a value to readValue method.
protected abstract gov.aps.jca.CAStatus	readValue(gov.aps.jca.dbr.DBR_TIME_LABELS_Enum value, gov.aps.jca.cas.ProcessVariableReadCallback asyncReadCallback) Read value.
gov.aps.jca.CAStatus	write(gov.aps.jca.dbr.DBR value, gov.aps.jca.cas.ProcessVariableWriteCallback asyncWriteCallback) Casts DBR to DBR_Enum and delegates operation of writing a value to writeValue method.
protected abstract gov.aps.jca.CAStatus	writeValue(gov.aps.jca.dbr.DBR_Enum value, gov.aps.jca.cas.ProcessVariableWriteCallback asyncWriteCallback) Write value.

Methods inherited from class gov.aps.jca.cas.ProcessVariable

createChannel, destroy, getAckS, getDimensionSize, getEnumLabels, getEventCallback, getMaxDimension, getName, interestDelete, interestRegister, isAckT, printInfo, printInfo, registerChannel, setAckS, setAckT, setEventCallback, unregisterChannel

Methods inherited from class java.lang.Object

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

Constructor Detail

EnumProcessVariable

public EnumProcessVariable(String name,
                           gov.aps.jca.cas.ProcessVariableEventCallback eventCallback)

Enum PV constructor.

Parameters:

name - process variable name.

eventCallback - event callback, can be null.

Method Detail

getType

public gov.aps.jca.dbr.DBRType getType()

Return DBRType.ENUM type as native type.

Specified by:

getType in class gov.aps.jca.cas.ProcessVariable

See Also:

ProcessVariable.getType()

read

public gov.aps.jca.CAStatus read(gov.aps.jca.dbr.DBR value,
                                 gov.aps.jca.cas.ProcessVariableReadCallback asyncReadCallback)
                          throws gov.aps.jca.CAException

Casts DBR to DBR_TIME_LABELS_Enum, sets labels returned by getEnumLabels() and delegates operation of reading a value to readValue method.

Specified by:

read in class gov.aps.jca.cas.ProcessVariable

Throws:

gov.aps.jca.CAException

See Also:

ProcessVariable.read(gov.aps.jca.dbr.DBR, gov.aps.jca.cas.ProcessVariableReadCallback)

readValue

protected abstract gov.aps.jca.CAStatus readValue(gov.aps.jca.dbr.DBR_TIME_LABELS_Enum value,
                                                  gov.aps.jca.cas.ProcessVariableReadCallback asyncReadCallback)
                                           throws gov.aps.jca.CAException

Read value. Reference implementation:

        {
 
                // for async. completion, return null,
                // set value (and status) to enumValue and
                // report completion using asyncReadCallback callback.
                // return null;
        
                // BEGIN optional (to override defaults) 

                // set status and severity
                enumValue.setStatus(Status.);
                enumValue.setSeverity(Severity.);
                
                // set timestamp
                enumValue.setTimestamp(timestamp);
                
                // END optional (to override defaults)
                
                // set value to given DBR (example of copying value)
                // given DBR has already allocated an array of elements client has requested
                // it contains maximum number of elements to fill
                short[] arrayValue = value.getEnumValue();
                int elementCount = Math.min(.length, arrayValue.length);
                System.arraycopy(, 0, arrayValue, 0, elementCount);
 
                // return read completion status
                return CAStatus.NORMAL;
        } 
 
 

Throws:

gov.aps.jca.CAException

See Also:

ProcessVariable.read(gov.aps.jca.dbr.DBR, gov.aps.jca.cas.ProcessVariableReadCallback)

write

public gov.aps.jca.CAStatus write(gov.aps.jca.dbr.DBR value,
                                  gov.aps.jca.cas.ProcessVariableWriteCallback asyncWriteCallback)
                           throws gov.aps.jca.CAException

Casts DBR to DBR_Enum and delegates operation of writing a value to writeValue method.

Specified by:

write in class gov.aps.jca.cas.ProcessVariable

Throws:

gov.aps.jca.CAException

See Also:

ProcessVariable.write(gov.aps.jca.dbr.DBR, gov.aps.jca.cas.ProcessVariableWriteCallback)

writeValue

protected abstract gov.aps.jca.CAStatus writeValue(gov.aps.jca.dbr.DBR_Enum value,
                                                   gov.aps.jca.cas.ProcessVariableWriteCallback asyncWriteCallback)
                                            throws gov.aps.jca.CAException

Write value. Reference implementation:

        {
 
                // for async. completion, return null,
                // set value (and status) from enumValue,
                // notify if there is an interest and
                // report completion using asyncWriteCallback callback.
                // return null;
 
                // set value from given DBR here (scalar example)
      this.value = value.getEnumValue()[0];
 
            // notify, set appropirate Monitor mask (VALUE, LOG, ALARM)
            if (status == CAStatus.NORMAL && interest)
      {
                        DBR monitorDBR = AbstractCASResponseHandler.createDBRforReading(this);
                        ((DBR_Enum)monitorDBR).getEnumValue()[0] = this.value;

                        // set labels
                        ((LABELS)monitorDBR).setLabels(getEnumLabels());

                        // set status, severity and time here (see readValue method example)
                        fillInStatusAndTime((TIME)monitorDBR);
                
                eventCallback.postEvent(Monitor.VALUE|Monitor.LOG, value);
                }
 
                // return read completion status
                return CAStatus.NORMAL;
 }
 

Throws:

gov.aps.jca.CAException

See Also:

ProcessVariable.write(gov.aps.jca.dbr.DBR, gov.aps.jca.cas.ProcessVariableWriteCallback)