new UpdateConstraintFactory()
Factory for the constraint types.
An instance can be obtained by calling diffusion.updateConstraints().
- Since:
-
- 6.2
Methods
-
jsonValue()
-
Create a constraint that partially matches the current topic value.
The topic must be a JSON topic. The diffusion.topicUpdate.PartialJSON partially describes the structure of a JSON value.
Returns:
the constraint
-
locked(lock)
-
Create a constraint requiring a lock to be held by the session.
This can be used to coordinate operations between multiple sessions.
Parameters:
Name Type Description lock
SessionLock the lock
Returns:
the constraint
-
noTopic()
-
Create a constraint requiring the path to have no topic.
This is useful when setting the first value of a topic being added using addAndSet without changing the value if the topic already exists. This constraint is unsatisfied if a topic is present at the path, making it unsuitable for operations that try to set topics without adding them.
Returns:
the constraint
-
noValue()
-
Create a constraint requiring the topic to have no value.
This is useful when setting the first value of a topic. This constraint is unsatisfied if no topic is present at the path, making it unsuitable for operations that try to add topics.
Returns:
the constraint
-
value(value, dataType)
-
Create a constraint requiring the current value of the topic to match the supplied value.
Create a constraint requiring the current value of the topic to match the supplied value.
If
dataType
is not specified, the data type is inferred from thevalue
parameter.This method is useful when changing the value of a topic. This constraint is unsatisfied if no topic is present at the path, making it unsuitable for operations that try to add topics.
When a string, int64 or double topic is updated to a {@code null} value, the topic is set to have no value. Use the #noValue() constraint to check if the topic has no value.
Parameters:
Name Type Description value
any the value
dataType
diffusion.datatypes.DataType the optional type of the values
Returns:
the constraint