com.nt.udc.aggregator.util

Class AggrCalcFields

java.lang.Object

com.nt.udc.aggregator.AggregatorModule

com.nt.udc.aggregator.util.AggrCalcFields

public class AggrCalcFields
extends AggregatorModule

This class contains all basic aggregator calculation operations. Currently, the following calculations are supported: - sum of two fields - max of two fields - keep of a field - growlist of a field See the appropriate method comments for more details.

Field Summary

Fields inherited from class com.nt.udc.aggregator.AggregatorModule

config, logger

Constructor Summary

Constructors

Constructor and Description
AggrCalcFields(ConfigIfc config, LoggerIfc logger) Creates an object to handle calculated aggregation fields.

Method Summary

Modifier and Type	Method and Description
void	addKeepFields(int[] fields) Adds more fields that need to be kept at "keep" time.
void	calc_growlist(NAR newRecord, NAR updatedRecord) Appends the values of the new record's List field with the existing list of the updated record.
void	calc_keep(NAR newRecord, NAR updatedRecord) Keeps the specified fields from the new record in the updated record.
void	calc_max(NAR newRecord, NAR updatedRecord) Compares the fields in the new record and the updated record, and keep the greater value in the updated record.
void	calc_strconcat(NAR newRecord, NAR updatedRecord) Concatenate the String fields in two records according to the settings of "strconcat", and store the result in the updated record.
void	calc_sum(NAR newRecord, NAR updatedRecord) Sum the fields in two records according to the settings of "sum", and store the result in the updated record.
protected void	getConfigData() This method should obtain the necessary information from the config class, in order to configure the module.
boolean	isSumOverflow(NAR newRecord, NAR oldRecord) Determines whether there would be overflow when summing the fields of the new record into the fields of the old record.
int[]	recordInitFields() Returns the fields that should be stored in a newly created record entry.
void	shutdown() This method should handle shutting down the routines that have been started by this class.

Methods inherited from class java.lang.Object

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

Constructor Detail

AggrCalcFields

public AggrCalcFields(ConfigIfc config,
                      LoggerIfc logger)

Creates an object to handle calculated aggregation fields.

Method Detail

getConfigData

protected void getConfigData()

Description copied from class: AggregatorModule

This method should obtain the necessary information from the config class, in order to configure the module.

Specified by:

getConfigData in class AggregatorModule

recordInitFields

public int[] recordInitFields()

Returns the fields that should be stored in a newly created record entry. The fields returned are those that this object uses/knows about.

Specified by:

recordInitFields in class AggregatorModule

Returns:

Array of integers, representing the fields to initialize.

addKeepFields

public void addKeepFields(int[] fields)

Adds more fields that need to be kept at "keep" time. Basically, this method should be used for the implied "keep" fields, so that the user doesn't have to specify the whole record in the rules file. This should only need to be called once.

Parameters:

fields - Int array of field ID's to keep.

calc_keep

public void calc_keep(NAR newRecord,
                      NAR updatedRecord)

Keeps the specified fields from the new record in the updated record. Note that this will overwrite any existing fields in the updated record. The fields need to be specified by the "keep" configuration file setting. This calculation works on all field types.

Parameters:

newRecord - incoming record

updatedRecord - updated record, from the table

calc_sum

public void calc_sum(NAR newRecord,
                     NAR updatedRecord)
              throws java.lang.ArithmeticException

Sum the fields in two records according to the settings of "sum", and store the result in the updated record. This calculation supports fields of the following types: - byte - short - integer - long Note that there is the possibility of summation overflow. This means that the resulting field cannot store the value of the new field and the existing field because of the data type limitiations. For example: int i = Integer.MAX_VALUE + 1; is an invalid statement. In this case, the method throws an ArithmeticException. If this exception is thrown, the new and updated records will not have been modified.

Parameters:

newRecord - Record containing the new values

updatedRecord - Record to contain the updated values

Throws:

java.lang.ArithmeticException

calc_max

public void calc_max(NAR newRecord,
                     NAR updatedRecord)

Compares the fields in the new record and the updated record, and keep the greater value in the updated record. This calculation is applied to those fields set in the "max" configuration file setting. This calculation supports fields of the following types: - byte - short - integer - long

Parameters:

newRecord - incoming record

updatedRecord - updated record, from the record table

calc_growlist

public void calc_growlist(NAR newRecord,
                          NAR updatedRecord)

Appends the values of the new record's List field with the existing list of the updated record. The lists used are those set in the "growlist" configuration setting. This calculation supports fields of the following types: - ListField

Parameters:

newRecord - incoming record

updatedRecord - updated record, from the record table

calc_strconcat

public void calc_strconcat(NAR newRecord,
                           NAR updatedRecord)

Concatenate the String fields in two records according to the settings of "strconcat", and store the result in the updated record. This calculation supports fields of the following types: - String

Parameters:

newRecord - Record containing the new values

updatedRecord - Record to contain the updated values

isSumOverflow

public boolean isSumOverflow(NAR newRecord,
                             NAR oldRecord)

Determines whether there would be overflow when summing the fields of the new record into the fields of the old record.

Parameters:

newRecord - Incoming record

oldRecord - Record that exists in the table

Returns:

true, if there is overflow.

shutdown

public void shutdown()

Description copied from class: AggregatorModule

This method should handle shutting down the routines that have been started by this class.

Specified by:

shutdown in class AggregatorModule