com.aquenos.cassandra.pvarchiver.server.database

Class ChannelMetaDataDAO.SampleBucketInformation

java.lang.Object

com.aquenos.cassandra.pvarchiver.server.database.ChannelMetaDataDAO.SampleBucketInformation

Enclosing interface:

ChannelMetaDataDAO

public static final class ChannelMetaDataDAO.SampleBucketInformation
extends Object

Value object representing the meta-data of a sample bucket. Each sample bucket belongs to a certain channel and decimation level and is identified by a unique ID. It stores samples with a time stamp that is equal to or greater than the bucket's start time.

Author:

Sebastian Marsching

Constructor Summary

Constructors

Constructor and Description
SampleBucketInformation(long bucketEndTime, long bucketStartTime, UUID channelDataId, String channelName, int decimationLevel) Creates a sample-bucket meta-data object.

Method Summary

Modifier and Type	Method and Description
boolean	equals(Object obj)
long	getBucketEndTime() Returns the end time of this sample bucket as the number of nanoseconds since epoch (January 1st, 1970, 00:00:00 UTC).
SampleBucketId	getBucketId() Returns the unique ID identifiying this sample bucket.
long	getBucketStartTime() Returns the start time of this sample bucket as the number of nanoseconds since epoch (January 1st, 1970, 00:00:00 UTC).
UUID	getChannelDataId() Returns the unique identifier that is associated with the data (samples) for the channel.
String	getChannelName() Returns the name of the channel for which this sample bucket stores data.
int	getDecimationLevel() Returns the decimation level for which this sample bucket stores data.
int	hashCode()
String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

SampleBucketInformation

public SampleBucketInformation(long bucketEndTime,
                               long bucketStartTime,
                               UUID channelDataId,
                               String channelName,
                               int decimationLevel)

Creates a sample-bucket meta-data object.

Parameters:

bucketEndTime - end time of this sample bucket as the number of nanoseconds since epoch (January 1st, 1970, 00:00:00 UTC).

bucketStartTime - start time of this sample bucket as the number of nanoseconds since epoch (January 1st, 1970, 00:00:00 UTC).

channelDataId - unique identifier associated with the data (samples) for the channel.

channelName - name of the channel for which this sample bucket stores data.

decimationLevel - decimation level for which this sample bucket stores data. The decimation level is identified by the number of seconds between two samples. A decimation level of zero specifies that this decimation level stores (undecimated) raw samples, which typically do not have a fixed period.

Throws:

IllegalArgumentException - if the channelName is the empty string, if the bucketStartTime is negative, and if the bucketEndTime is less than the bucketStartTime.

NullPointerException - if the channelDataId or the channelName is null.

Method Detail

getBucketEndTime

public long getBucketEndTime()

Returns the end time of this sample bucket as the number of nanoseconds since epoch (January 1st, 1970, 00:00:00 UTC). A bucket only stores sample with time stamps equal to or less than its end time. If there is a following bucket for the same channel and decimation level (a bucket with a greater start time), this bucket's end time must be strictly less than the following bucket's start time.

Returns:

end time of this bucket as the number of nanoseconds since epoch.

getBucketId

public SampleBucketId getBucketId()

Returns the unique ID identifiying this sample bucket.

Returns:

unique bucket ID.

getBucketStartTime

public long getBucketStartTime()

Returns the start time of this sample bucket as the number of nanoseconds since epoch (January 1st, 1970, 00:00:00 UTC). A bucket only stores sample with time stamps equal to or greater than its start time. If there is a preceding bucket for the same channel and decimation level (a bucket with a lesser start time), this bucket's start time must be strictly greater than the preceding bucket's end time.

This number is the same one as the one that is provided as part of the bucket ID returned by getBucketId().

Returns:

start time of this bucket as the number of nanoseconds since epoch.

getChannelDataId

public UUID getChannelDataId()

Returns the unique identifier that is associated with the data (samples) for the channel. While a channel's name might change due to renaming, the data ID will be permanent (until the channel is deleted), so even after renaming a channel, its associated data can still be found.

This identifier is the same one as the one that is provided as part of the bucket ID returned by getBucketId().

Returns:

unique identifier associated with the channel's data.

getChannelName

public String getChannelName()

Returns the name of the channel for which this sample bucket stores data.

Returns:

name identifying the channel to which this bucket belongs.

getDecimationLevel

public int getDecimationLevel()

Returns the decimation level for which this sample bucket stores data. The decimation level is identified by the number of seconds between two samples. A decimation level of zero specifies that this decimation level stores (undecimated) raw samples, which typically do not have a fixed period.

This number is the same one as the one that is provided as part of the bucket ID returned by getBucketId().

Returns:

decimation level of this bucket.

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

toString

public String toString()

Overrides:

toString in class Object