Package org.elasticsearch.index.seqno

Class SequenceNumbers

java.lang.Object

org.elasticsearch.index.seqno.SequenceNumbers

public class SequenceNumbers
extends java.lang.Object

A utility class for handling sequence numbers.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	SequenceNumbers.CommitInfo

Field Summary

Fields

Modifier and Type	Field	Description
static java.lang.String	LOCAL_CHECKPOINT_KEY
static java.lang.String	MAX_SEQ_NO
static long	NO_OPS_PERFORMED	Represents no operations have been performed on the shard.
static long	PRE_60_NODE_CHECKPOINT	Represents a checkpoint coming from a pre-6.0 node
static long	UNASSIGNED_SEQ_NO	Represents an unassigned sequence number (e.g., can be used on primary operations before they are executed).

Constructor Summary

Constructors

Constructor	Description
SequenceNumbers()

Method Summary

Modifier and Type	Method	Description
static SequenceNumbers.CommitInfo	loadSeqNoInfoFromLuceneCommit(java.lang.Iterable<java.util.Map.Entry<java.lang.String,java.lang.String>> commitData)	Reads the sequence number stats from the commit data (maximum sequence number and local checkpoint).
static long	max(long maxSeqNo, long seqNo)	Compute the maximum of the given current maximum sequence number and the specified sequence number, accounting for the fact that the current maximum sequence number could be NO_OPS_PERFORMED or UNASSIGNED_SEQ_NO.
static long	min(long minSeqNo, long seqNo)	Compute the minimum of the given current minimum sequence number and the specified sequence number, accounting for the fact that the current minimum sequence number could be NO_OPS_PERFORMED or UNASSIGNED_SEQ_NO.

Methods inherited from class java.lang.Object

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

Field Detail

LOCAL_CHECKPOINT_KEY

public static final java.lang.String LOCAL_CHECKPOINT_KEY

See Also:

Constant Field Values

MAX_SEQ_NO

public static final java.lang.String MAX_SEQ_NO

See Also:

Constant Field Values

PRE_60_NODE_CHECKPOINT

public static final long PRE_60_NODE_CHECKPOINT

Represents a checkpoint coming from a pre-6.0 node

See Also:

Constant Field Values

UNASSIGNED_SEQ_NO

public static final long UNASSIGNED_SEQ_NO

Represents an unassigned sequence number (e.g., can be used on primary operations before they are executed).

See Also:

Constant Field Values

NO_OPS_PERFORMED

public static final long NO_OPS_PERFORMED

Represents no operations have been performed on the shard.

See Also:

Constant Field Values

Constructor Detail

SequenceNumbers

public SequenceNumbers()

Method Detail

loadSeqNoInfoFromLuceneCommit

public static SequenceNumbers.CommitInfo loadSeqNoInfoFromLuceneCommit(java.lang.Iterable<java.util.Map.Entry<java.lang.String,java.lang.String>> commitData)

Reads the sequence number stats from the commit data (maximum sequence number and local checkpoint).

Parameters:

commitData - the commit data

Returns:

the sequence number stats

min

public static long min(long minSeqNo,
                       long seqNo)

Compute the minimum of the given current minimum sequence number and the specified sequence number, accounting for the fact that the current minimum sequence number could be NO_OPS_PERFORMED or UNASSIGNED_SEQ_NO. When the current minimum sequence number is not NO_OPS_PERFORMED nor UNASSIGNED_SEQ_NO, the specified sequence number must not be UNASSIGNED_SEQ_NO.

Parameters:

minSeqNo - the current minimum sequence number

seqNo - the specified sequence number

Returns:

the new minimum sequence number

max

public static long max(long maxSeqNo,
                       long seqNo)

Compute the maximum of the given current maximum sequence number and the specified sequence number, accounting for the fact that the current maximum sequence number could be NO_OPS_PERFORMED or UNASSIGNED_SEQ_NO. When the current maximum sequence number is not NO_OPS_PERFORMED nor UNASSIGNED_SEQ_NO, the specified sequence number must not be UNASSIGNED_SEQ_NO.

Parameters:

maxSeqNo - the current maximum sequence number

seqNo - the specified sequence number

Returns:

the new maximum sequence number