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* Licensed to the Apache Software Foundation (ASF) under one
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* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
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* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.flink.optimizer.dataproperties;
/**
* An enumeration of the the different types of distributing data across partitions or
* parallel workers.
*/
public enum PartitioningProperty {
/**
* Any possible way of data distribution, including random partitioning and full replication.
*/
ANY_DISTRIBUTION,
/**
* A random disjunct (non-replicated) data distribution, where each datum is contained in one partition only.
* This is for example the result of parallel scans of data in a file system like HDFS,
* or the result of a round-robin data distribution.
*/
RANDOM_PARTITIONED,
/**
* A hash partitioning on a certain key.
*/
HASH_PARTITIONED,
/**
* A range partitioning on a certain key.
*/
RANGE_PARTITIONED,
/**
* A not further specified partitioning on a key (hash-, or range partitioning, or some other scheme even).
*/
ANY_PARTITIONING,
/**
*Full replication of the data to each parallel instance.
*/
FULL_REPLICATION,
/**
* A forced even re-balancing. All partitions are guaranteed to have almost the same number of records.
*/
FORCED_REBALANCED,
/**
* A custom partitioning, accompanied by a {@link org.apache.flink.api.common.functions.Partitioner}.
*/
CUSTOM_PARTITIONING;
/**
* Checks, if this property represents in fact a partitioning. That is,
* whether this property is not equal to <tt>PartitionProperty.FULL_REPLICATION</tt>.
*
* @return True, if this enum constant is unequal to <tt>PartitionProperty.FULL_REPLICATION</tt>,
* false otherwise.
*/
public boolean isPartitioned() {
return this != FULL_REPLICATION && this != FORCED_REBALANCED && this != ANY_DISTRIBUTION;
}
/**
* Checks, if this property represents a full replication.
*
* @return True, if this enum constant is equal to <tt>PartitionProperty.FULL_REPLICATION</tt>,
* false otherwise.
*/
public boolean isReplication() {
return this == FULL_REPLICATION;
}
/**
* Checks if this property presents a partitioning that is not random, but on a partitioning key.
*
* @return True, if the data is partitioned on a key.
*/
public boolean isPartitionedOnKey() {
return isPartitioned() && this != RANDOM_PARTITIONED;
}
/**
* Checks, if this property represents a partitioning that is computable.
* A computable partitioning can be recreated through an algorithm. If two sets of data are to
* be co-partitioned, it is crucial, that the partitioning schemes are computable.
* <p>
* Examples for computable partitioning schemes are hash- or range-partitioning. An example for a non-computable
* partitioning is the implicit partitioning that exists though a globally unique key.
*
* @return True, if this enum constant is a re-computable partitioning.
*/
public boolean isComputablyPartitioned() {
return this == HASH_PARTITIONED || this == RANGE_PARTITIONED || this == CUSTOM_PARTITIONING;
}
}