Package org.infinispan.conflict

Enum MergePolicy

java.lang.Object

java.lang.Enum<MergePolicy>

org.infinispan.conflict.MergePolicy

All Implemented Interfaces:

Serializable, Comparable<MergePolicy>, EntryMergePolicy

public enum MergePolicy
extends Enum<MergePolicy>
implements EntryMergePolicy

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	MergePolicy.UnsupportedMergePolicy

Enum Constant Summary

Enum Constants

Enum Constant	Description
CUSTOM
NONE
PREFERRED_ALWAYS
PREFERRED_NON_NULL
REMOVE_ALL

Method Summary

Modifier and Type	Method	Description
static MergePolicy	fromConfiguration(EntryMergePolicy policy)
static MergePolicy	fromString(String str)
org.infinispan.container.entries.CacheEntry	merge(org.infinispan.container.entries.CacheEntry preferredEntry, List otherEntries)	This method is called by ConflictManager.resolveConflicts() for each conflict discovered to determine which CacheEntry should be utilised.
static MergePolicy	valueOf(String name)	Returns the enum constant of this type with the specified name.
static MergePolicy[]	values()	Returns an array containing the constants of this enum type, in the order they are declared.

Enum Constant Detail

CUSTOM

public static final MergePolicy CUSTOM

NONE

public static final MergePolicy NONE

PREFERRED_ALWAYS

public static final MergePolicy PREFERRED_ALWAYS

PREFERRED_NON_NULL

public static final MergePolicy PREFERRED_NON_NULL

REMOVE_ALL

public static final MergePolicy REMOVE_ALL

Method Detail

values

public static MergePolicy[] values()

Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows:

for (MergePolicy c : MergePolicy.values())
    System.out.println(c);

Returns:

an array containing the constants of this enum type, in the order they are declared

valueOf

public static MergePolicy valueOf(String name)

Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)

Parameters:

name - the name of the enum constant to be returned.

Returns:

the enum constant with the specified name

Throws:

IllegalArgumentException - if this enum type has no constant with the specified name

NullPointerException - if the argument is null

merge

public org.infinispan.container.entries.CacheEntry merge(org.infinispan.container.entries.CacheEntry preferredEntry,
                                                         List otherEntries)

Description copied from interface: EntryMergePolicy

This method is called by ConflictManager.resolveConflicts() for each conflict discovered to determine which CacheEntry should be utilised. This merge policy is used when a user explicitly calls ConflictManager.resolveConflicts() as well as when a partition merge occurs with PartitionHandling.ALLOW_READ_WRITES set. In the event of a partition merge, we define the preferred partition as the partition whom's coordinator is coordinating the current merge.

Specified by:

merge in interface EntryMergePolicy

Parameters:

preferredEntry - During a partition merge, the preferredEntry is the primary replica of a CacheEntry stored in the partition that contains the most nodes or if partitions are equal the one with the largest topologyId. In the event of overlapping partitions, i.e. a node A is present in the topology of both partitions {A}, {A,B,C}, we pick {A} as the preferred partition as it will have the higher topologId because the other partition's topology is behind. During a non-merge call to ConflictManager.resolveConflicts(), the preferredEntry is simply the primary owner of an entry

otherEntries - a List of all other CacheEntry associated with a given Key.

Returns:

the winning CacheEntry to be utilised across the cluster, or null if all entries for a key should be removed.

fromString

public static MergePolicy fromString(String str)

fromConfiguration

public static MergePolicy fromConfiguration(EntryMergePolicy policy)