org.marid.db.dao

Interface DaqReader<T extends Serializable>

Type Parameters:

T - Data record type.

All Superinterfaces:

AutoCloseable, DaqMXBean

All Known Subinterfaces:

DaqWriter<T>, NumericReader, NumericWriter

public interface DaqReader<T extends Serializable>
extends DaqMXBean, AutoCloseable

Generic DAQ DAO.

Author:

Dmitry Ovchinnikov.

Method Summary

Modifier and Type	Method and Description
DataRecord<T>	fetchRecord(String tag, Instant instant) Get a tag record by tag and timestamp.
List<DataRecord<T>>	fetchRecords(Set<String> tags, Instant from, Instant to) Fetches all the records within the given time range.
Map<String,String>	hash(Instant from, Instant to, boolean includeData, String algorithm) Hashes record range.
long	tagCount(Instant from, Instant to) Get tag count within the given time range.
Set<String>	tags(Instant from, Instant to) Get all tags within the given time range.
Set<String>	tagsWithPrefix(String prefix) Get all tags with the given prefix.
Set<String>	tagsWithSuffix(String suffix) Get all tags with the given suffix.

Methods inherited from interface org.marid.db.dao.DaqMXBean

getRecordCount

Methods inherited from interface java.lang.AutoCloseable

close

Method Detail

tags

Set<String> tags(Instant from,
                 Instant to)

Get all tags within the given time range.

Parameters:

from - Lower bound (inclusive).

to - Upper bound (exclusive).

Returns:

Tag set.

tagsWithPrefix

Set<String> tagsWithPrefix(String prefix)

Get all tags with the given prefix.

Parameters:

prefix - Tag prefix.

Returns:

Tag set.

tagsWithSuffix

Set<String> tagsWithSuffix(String suffix)

Get all tags with the given suffix.

Parameters:

suffix - Tag suffix.

Returns:

Tag set.

tagCount

long tagCount(Instant from,
              Instant to)

Get tag count within the given time range.

Parameters:

from - Lower bound (inclusive).

to - Upper bound (exclusive).

Returns:

Tag count.

fetchRecord

DataRecord<T> fetchRecord(String tag,
                          Instant instant)

Get a tag record by tag and timestamp.

Parameters:

tag - Record tag.

instant - Timestamp.

Returns:

Data record.

fetchRecords

List<DataRecord<T>> fetchRecords(Set<String> tags,
                                 Instant from,
                                 Instant to)

Fetches all the records within the given time range.

Parameters:

tags - Tags to be fetched.

from - Lower bound (inclusive).

to - Upper bound (exclusive).

Returns:

Fetched records.

hash

Map<String,String> hash(Instant from,
                        Instant to,
                        boolean includeData,
                        String algorithm)

Hashes record range.

Parameters:

from - Lower bound (inclusive).

to - Upper bound (exclusive).

includeData - Whether include data or not.

algorithm - Digest algorithm (e.g. SHA-1 or MD5).

Returns:

Hashes.