Core

Hazelcast Core objects

class Member(address, uuid, is_lite_member=False, attributes={})

Bases: object

Represents a member in the cluster with its address, uuid, lite member status and attributes.

class Address(host, port)

Bases: object

Represents an address of a member in the cluster.

class DistributedObjectInfo(name, service_name)

Bases: object

Represents name of the Distributed Object and the name of service which it belongs to.

class EntryView

Bases: object

EntryView represents a readonly view of a map entry.

key = None

The key of the entry.

value = None

The value of the entry.

cost = None

The cost in bytes of the entry.

creation_time = None

The creation time of the entry.

expiration_time = None

The expiration time of the entry.

hits = None

Number of hits of the entry.

last_access_time = None

The last access time for the entry.

last_stored_time = None

The last store time for the value.

last_update_time = None

The last time the value was updated.

version = None

The version of the entry.

eviction_criteria_number = None

The criteria number for eviction.

ttl = None

The last set time to live second.

class MemberSelector

Bases: object

Subclasses of this class select members that are capable of executing a special kind of task. The select(Member) method is called for every available member in the cluster and it is up to the implementation to decide if the member is going to be used or not.

select(member)

Decides if the given member will be part of an operation or not.

Parameters

member – (Member), the member instance to decide upon.

Returns

(bool), True if the member should take part in the operation, False otherwise.

class DataMemberSelector

Bases: hazelcast.core.MemberSelector

select(member)

Decides if the given member will be part of an operation or not.

Parameters

member – (Member), the member instance to decide upon.

Returns

(bool), True if the member should take part in the operation, False otherwise.

class HazelcastJsonValue(value)

Bases: object

HazelcastJsonValue is a wrapper for JSON formatted strings. It is preferred to store HazelcastJsonValue instead of Strings for JSON formatted strings. Users can run predicates and use indexes on the attributes of the underlying JSON strings.

HazelcastJsonValue is queried using Hazelcast’s querying language. See Distributed Query section.

In terms of querying, numbers in JSON strings are treated as either Long or Double in the Java side. str, bool and None are treated as String, boolean and null respectively.

HazelcastJsonValue keeps given string as it is. Strings are not checked for being valid. Ill-formatted JSON strings may cause false positive or false negative results in queries.

HazelcastJsonValue can also be constructed from JSON serializable objects. In that case, objects are converted to JSON strings and stored as such. If an error occurs during the conversion, it is raised directly.

None values are not allowed.

to_string()

Returns unaltered string that was used to create this object.

Returns

(str), original string

loads()

Deserializes the string that was used to create this object and returns as Python object.

Returns

(object), Python object represented by the original string