public interface Constraint
Constraint objects are used to determine if mutations will be applied to a table.
This interface expects implementers to return violation codes. The reason codes are returned instead of arbitrary strings to encourage conciseness. Conciseness is needed because violations are aggregated. If a user sends a batch of 10,000 mutations to Accumulo, only aggregated counts about which violations occurred are returned. If the constraint implementer were allowed to return arbitrary violation strings like the following:
Value "abc" is not a number
Value "vbg" is not a number
This would not aggregate very well, because the same violation is represented with two different strings.
|Modifier and Type||Interface and Description|
The environment within which a constraint exists.
|Modifier and Type||Method and Description|
Checks a mutation for constraint violations.
Gets a short, one-sentence description of what a given violation code means.
String getViolationDescription(short violationCode)
violationCode- numeric violation code
List<Short> check(Constraint.Environment env, Mutation mutation)
env- constraint environment
mutation- mutation to check
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