Package org.apache.hadoop.hdfs.server.federation.store.driver.impl

Class StateStoreZooKeeperImpl

java.lang.Object

org.apache.hadoop.hdfs.server.federation.store.driver.StateStoreDriver

org.apache.hadoop.hdfs.server.federation.store.driver.impl.StateStoreBaseImpl

org.apache.hadoop.hdfs.server.federation.store.driver.impl.StateStoreSerializableImpl

org.apache.hadoop.hdfs.server.federation.store.driver.impl.StateStoreZooKeeperImpl

All Implemented Interfaces:

StateStoreRecordOperations

public class StateStoreZooKeeperImpl
extends StateStoreSerializableImpl

StateStoreDriver driver implementation that uses ZooKeeper as a backend.

The structure of the znodes in the ensemble is: PARENT_PATH |--- MOUNT |--- MEMBERSHIP |--- REBALANCER |--- ROUTERS |--- DISABLE_NAMESERVICE

Field Summary

Fields inherited from class org.apache.hadoop.hdfs.server.federation.store.driver.impl.StateStoreSerializableImpl

COLON_MARK, SLASH_MARK

Constructor Summary

Constructors

Constructor	Description
StateStoreZooKeeperImpl()

Method Summary

Modifier and Type	Method	Description
void	close()	Close the State Store driver connection.
<T extends BaseRecord> QueryResult<T>	get(java.lang.Class<T> clazz)	Get all records of the requested record class from the data store.
boolean	initDriver()	Prepare the driver to access data storage.
<T extends BaseRecord> boolean	initRecordStorage(java.lang.String className, java.lang.Class<T> clazz)	Initialize storage for a single record class.
boolean	isDriverReady()	Check if the driver is currently running and the data store connection is valid.
<T extends BaseRecord> StateStoreOperationResult	putAll(java.util.List<T> records, boolean update, boolean error)	Creates multiple records.
<T extends BaseRecord> int	remove(java.lang.Class<T> clazz, Query<T> query)	Remove multiple records of a specific class that match a query.
<T extends BaseRecord> boolean	removeAll(java.lang.Class<T> clazz)	Remove all records of this class from the store.
void	setEnableConcurrent(boolean enableConcurrent)

Methods inherited from class org.apache.hadoop.hdfs.server.federation.store.driver.impl.StateStoreSerializableImpl

getOriginalPrimaryKey, getPrimaryKey, init, newRecord, serialize, serializeString

Methods inherited from class org.apache.hadoop.hdfs.server.federation.store.driver.impl.StateStoreBaseImpl

get, getMultiple, put, remove

Methods inherited from class org.apache.hadoop.hdfs.server.federation.store.driver.StateStoreDriver

getConf, getIdentifier, getMetrics, getTime, verifyDriverReady

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

StateStoreZooKeeperImpl

public StateStoreZooKeeperImpl()

Method Detail

initDriver

public boolean initDriver()

Description copied from class: StateStoreDriver

Prepare the driver to access data storage.

Specified by:

initDriver in class StateStoreDriver

Returns:

True if the driver was successfully initialized. If false is returned, the state store will periodically attempt to re-initialize the driver and the router will remain in safe mode until the driver is initialized.

initRecordStorage

public <T extends BaseRecord> boolean initRecordStorage(java.lang.String className,
                                                        java.lang.Class<T> clazz)

Description copied from class: StateStoreDriver

Initialize storage for a single record class.

Specified by:

initRecordStorage in class StateStoreDriver

Type Parameters:

T - Type of the state store record.

Parameters:

className - String reference of the record class to initialize, used to construct paths and file names for the record. Determined by configuration settings for the specific driver.

clazz - Record type corresponding to the provided name.

Returns:

True if successful, false otherwise.

setEnableConcurrent

@VisibleForTesting
public void setEnableConcurrent(boolean enableConcurrent)

close

public void close()
           throws java.lang.Exception

Description copied from class: StateStoreDriver

Close the State Store driver connection.

Specified by:

close in class StateStoreDriver

Throws:

java.lang.Exception - if something goes wrong while closing the state store driver connection.

isDriverReady

public boolean isDriverReady()

Description copied from class: StateStoreDriver

Check if the driver is currently running and the data store connection is valid.

Specified by:

isDriverReady in class StateStoreDriver

Returns:

True if the driver is initialized and the data store is ready.

get

public <T extends BaseRecord> QueryResult<T> get(java.lang.Class<T> clazz)
                                          throws java.io.IOException

Description copied from interface: StateStoreRecordOperations

Get all records of the requested record class from the data store. To use the default implementations in this class, getAll must return new instances of the records on each call. It is recommended to override the default implementations for better performance.

Type Parameters:

T - Record class of the records.

Parameters:

clazz - Class of record to fetch.

Returns:

List of all records that match the class.

Throws:

java.io.IOException - Throws exception if unable to query the data store.

putAll

public <T extends BaseRecord> StateStoreOperationResult putAll(java.util.List<T> records,
                                                               boolean update,
                                                               boolean error)
                                                        throws java.io.IOException

Description copied from interface: StateStoreRecordOperations

Creates multiple records. Optionally updates existing records that have the same primary key.

Type Parameters:

T - Record class of the records.

Parameters:

records - List of data records to update or create. All records must be of class clazz.

update - True if update of exiting record is allowed.

error - True if an error should be returned when inserting an existing record. Only used if allowUpdate = false.

Returns:

The result of the putAll operation.

Throws:

java.io.IOException - Throws exception if unable to query the data store.

remove

public <T extends BaseRecord> int remove(java.lang.Class<T> clazz,
                                         Query<T> query)
                                  throws java.io.IOException

Description copied from interface: StateStoreRecordOperations

Remove multiple records of a specific class that match a query. Requires the getAll implementation to fetch fresh records on each call.

Type Parameters:

T - Record class of the records.

Parameters:

clazz - The class to match the records with.

query - Query to filter what to remove.

Returns:

The number of records removed.

Throws:

java.io.IOException - Throws exception if unable to query the data store.

removeAll

public <T extends BaseRecord> boolean removeAll(java.lang.Class<T> clazz)
                                         throws java.io.IOException

Description copied from interface: StateStoreRecordOperations

Remove all records of this class from the store.

Type Parameters:

T - Record class of the records.

Parameters:

clazz - Class of records to remove.

Returns:

True if successful.

Throws:

java.io.IOException - Throws exception if unable to query the data store.