org.apache.storm.state

Class BaseBinaryStateIterator<K,V>

java.lang.Object

org.apache.storm.state.BaseStateIterator<K,V,byte[],byte[]>

org.apache.storm.state.BaseBinaryStateIterator<K,V>

All Implemented Interfaces:

Iterator<Map.Entry<K,V>>

Direct Known Subclasses:

HBaseKeyValueStateIterator, RedisKeyValueStateIterator

public abstract class BaseBinaryStateIterator<K,V>
extends BaseStateIterator<K,V,byte[],byte[]>

Base implementation of iterator over KeyValueState which encoded types of key and value are both binary type.

Constructor Summary

Constructors

Constructor and Description
BaseBinaryStateIterator(Iterator<Map.Entry<byte[],byte[]>> pendingPrepareIterator, Iterator<Map.Entry<byte[],byte[]>> pendingCommitIterator) Constructor.

Method Summary

Modifier and Type	Method and Description
protected abstract K	decodeKey(byte[] key) Decode key to convert byte array to state key type.
protected abstract V	decodeValue(byte[] value) Decode value to convert byte array to state value type.
protected abstract boolean	isEndOfDataFromStorage() Check whether end of data is reached from storage state KVs.
protected abstract boolean	isTombstoneValue(byte[] value) Check whether the value is tombstone (deletion mark) value.
protected abstract Iterator<Map.Entry<byte[],byte[]>>	loadChunkFromStateStorage() Load some part of state KVs from storage and returns iterator of cached data from storage.

Methods inherited from class org.apache.storm.state.BaseStateIterator

hasNext, next, remove

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Iterator

forEachRemaining

Constructor Detail

BaseBinaryStateIterator

public BaseBinaryStateIterator(Iterator<Map.Entry<byte[],byte[]>> pendingPrepareIterator,
                               Iterator<Map.Entry<byte[],byte[]>> pendingCommitIterator)

Constructor.

Parameters:

pendingPrepareIterator - The iterator of pendingPrepare

pendingCommitIterator - The iterator of pendingCommit

Method Detail

loadChunkFromStateStorage

protected abstract Iterator<Map.Entry<byte[],byte[]>> loadChunkFromStateStorage()

Load some part of state KVs from storage and returns iterator of cached data from storage.

Specified by:

loadChunkFromStateStorage in class BaseStateIterator<K,V,byte[],byte[]>

Returns:

Iterator of loaded state KVs

isEndOfDataFromStorage

protected abstract boolean isEndOfDataFromStorage()

Check whether end of data is reached from storage state KVs.

Specified by:

isEndOfDataFromStorage in class BaseStateIterator<K,V,byte[],byte[]>

Returns:

whether end of data is reached from storage state KVs

decodeKey

protected abstract K decodeKey(byte[] key)

Decode key to convert byte array to state key type.

Specified by:

decodeKey in class BaseStateIterator<K,V,byte[],byte[]>

Parameters:

key - byte array encoded key

Returns:

Decoded value of key

decodeValue

protected abstract V decodeValue(byte[] value)

Decode value to convert byte array to state value type.

Specified by:

decodeValue in class BaseStateIterator<K,V,byte[],byte[]>

Parameters:

value - byte array encoded value

Returns:

Decoded value of value

isTombstoneValue

protected abstract boolean isTombstoneValue(byte[] value)

Check whether the value is tombstone (deletion mark) value.

Specified by:

isTombstoneValue in class BaseStateIterator<K,V,byte[],byte[]>

Parameters:

value - the value to check

Returns:

true if the value is tombstone, false otherwise