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public final static LogPerBucketingStrategy<Object> forKnownKeys(Iterable<? extends Object> knownKeys)
A strategy defined for some given set of known keys.
Unlike knownBounded, this strategy maps keys a bounded set of identifiers, and permits the use of non-singleton keys in LoggingApi.per(T, LogPerBucketingStrategy<T>).
If keys outside this set are used this strategy returns null, and log aggregation will not occur. Duplicates in knownKeys are ignored.