org.apache.hadoop.hbase.client.AsyncTableRegionLocator Maven / Gradle / Ivy
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* to you under the Apache License, Version 2.0 (the
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*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
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* See the License for the specific language governing permissions and
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*/
package org.apache.hadoop.hbase.client;
import java.io.IOException;
import java.util.List;
import java.util.concurrent.CompletableFuture;
import java.util.stream.Collectors;
import org.apache.hadoop.hbase.HRegionLocation;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.util.Pair;
import org.apache.yetus.audience.InterfaceAudience;
/**
* The asynchronous version of RegionLocator.
*
* Usually the implementations will not throw any exception directly, you need to get the exception
* from the returned {@link CompletableFuture}.
* @since 2.0.0
*/
@InterfaceAudience.Public
public interface AsyncTableRegionLocator {
/**
* Gets the fully qualified table name instance of the table whose region we want to locate.
*/
TableName getName();
/**
* Finds the region on which the given row is being served. Does not reload the cache.
*
* Returns the location of the region to which the row belongs.
* @param row Row to find.
*/
default CompletableFuture getRegionLocation(byte[] row) {
return getRegionLocation(row, false);
}
/**
* Finds the region on which the given row is being served.
*
* Returns the location of the region to which the row belongs.
* @param row Row to find.
* @param reload true to reload information or false to use cached information
*/
default CompletableFuture getRegionLocation(byte[] row, boolean reload) {
return getRegionLocation(row, RegionInfo.DEFAULT_REPLICA_ID, reload);
}
/**
* Finds the region with the given replicaId on which the given row is being served.
*
* Returns the location of the region with the given replicaId to which the row
* belongs.
* @param row Row to find.
* @param replicaId the replica id of the region
*/
default CompletableFuture getRegionLocation(byte[] row, int replicaId) {
return getRegionLocation(row, replicaId, false);
}
/**
* Finds the region with the given replicaId on which the given row is being served.
*
* Returns the location of the region with the given replicaId to which the row
* belongs.
* @param row Row to find.
* @param replicaId the replica id of the region
* @param reload true to reload information or false to use cached information
*/
CompletableFuture getRegionLocation(byte[] row, int replicaId, boolean reload);
/**
* Find all the replicas for the region on which the given row is being served.
* @param row Row to find.
* @return Locations for all the replicas of the row.
*/
default CompletableFuture> getRegionLocations(byte[] row) {
return getRegionLocations(row, false);
}
/**
* Find all the replicas for the region on which the given row is being served.
* @param row Row to find.
* @param reload true to reload information or false to use cached information
* @return Locations for all the replicas of the row.
*/
CompletableFuture> getRegionLocations(byte[] row, boolean reload);
/**
* Retrieves all of the regions associated with this table.
*
* Usually we will go to meta table directly in this method so there is no {@code reload}
* parameter.
*
* Notice that the location for region replicas other than the default replica are also returned.
* @return a {@link List} of all regions associated with this table.
*/
CompletableFuture> getAllRegionLocations();
/**
* Gets the starting row key for every region in the currently open table.
*
* This is mainly useful for the MapReduce integration.
* @return Array of region starting row keys
* @throws IOException if a remote or network exception occurs
*/
default CompletableFuture> getStartKeys() throws IOException {
return getStartEndKeys().thenApply(
startEndKeys -> startEndKeys.stream().map(Pair::getFirst).collect(Collectors.toList()));
}
/**
* Gets the ending row key for every region in the currently open table.
*
* This is mainly useful for the MapReduce integration.
* @return Array of region ending row keys
* @throws IOException if a remote or network exception occurs
*/
default CompletableFuture> getEndKeys() throws IOException {
return getStartEndKeys().thenApply(
startEndKeys -> startEndKeys.stream().map(Pair::getSecond).collect(Collectors.toList()));
}
/**
* Gets the starting and ending row keys for every region in the currently open table.
*
* This is mainly useful for the MapReduce integration.
* @return Pair of arrays of region starting and ending row keys
* @throws IOException if a remote or network exception occurs
*/
default CompletableFuture>> getStartEndKeys() throws IOException {
return getAllRegionLocations().thenApply(
locs -> locs.stream().filter(loc -> RegionReplicaUtil.isDefaultReplica(loc.getRegion()))
.map(HRegionLocation::getRegion).map(r -> Pair.newPair(r.getStartKey(), r.getEndKey()))
.collect(Collectors.toList()));
}
/**
* Clear all the entries in the region location cache.
*
* This may cause performance issue so use it with caution.
*/
void clearRegionLocationCache();
}