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

Class StateStoreFileSystemImpl

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.StateStoreFileBaseImpl

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

All Implemented Interfaces:

StateStoreRecordOperations

public class StateStoreFileSystemImpl
extends StateStoreFileBaseImpl

StateStoreDriver implementation based on a filesystem. The common implementation uses HDFS as a backend. The path can be specified setting dfs.federation.router.store.driver.fs.path=hdfs://host:port/path/to/store.

Field Summary

Fields

Modifier and Type	Field	Description
static final String	FEDERATION_STORE_FS_PATH	Configuration keys.

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

COLON_MARK, SLASH_MARK

Constructor Summary

Constructors

Constructor	Description
StateStoreFileSystemImpl()

Method Summary

Modifier and Type	Method	Description
void	close()	Close the State Store driver connection.
protected boolean	exists(String path)	Check if a path exists.
protected List<String>	getChildren(String pathName)	Get the children for a path.
protected int	getConcurrentFilesAccessNumThreads()
protected <T extends BaseRecord> BufferedReader	getReader(String pathName)	Get the reader of a record for the file system.
protected String	getRootDir()	Get root directory.
<T extends BaseRecord> BufferedWriter	getWriter(String pathName)	Get the writer of a record for the file system.
protected boolean	mkdir(String path)	Make a directory.
protected boolean	remove(String path)	Remove a file.
protected boolean	rename(String src, String dst)	Rename a file.

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

get, initDriver, initRecordStorage, isDriverReady, isOldTempRecord, putAll, remove, removeAll, setInitialized

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, remove, removeMultiple

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

getConf, getIdentifier, getMetrics, getTime, handleOverwriteAndDelete, verifyDriverReady

Methods inherited from class java.lang.Object

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

Field Details

FEDERATION_STORE_FS_PATH

public static final String FEDERATION_STORE_FS_PATH

Configuration keys.

See Also:

• Constant Field Values

Constructor Details

StateStoreFileSystemImpl

public StateStoreFileSystemImpl()

Method Details

exists

protected boolean exists(String path)

Description copied from class: StateStoreFileBaseImpl

Check if a path exists.

Specified by:

exists in class StateStoreFileBaseImpl

Parameters:

path - Path to check.

Returns:

If the path exists.

mkdir

protected boolean mkdir(String path)

Description copied from class: StateStoreFileBaseImpl

Make a directory.

Specified by:

mkdir in class StateStoreFileBaseImpl

Parameters:

path - Path of the directory to create.

Returns:

If the directory was created.

rename

protected boolean rename(String src,
 String dst)

Description copied from class: StateStoreFileBaseImpl

Rename a file. This should be atomic.

Specified by:

rename in class StateStoreFileBaseImpl

Parameters:

src - Source name.

dst - Destination name.

Returns:

If the rename was successful.

remove

protected boolean remove(String path)

Description copied from class: StateStoreFileBaseImpl

Remove a file.

Specified by:

remove in class StateStoreFileBaseImpl

Parameters:

path - Path for the file to remove

Returns:

If the file was removed.

getRootDir

protected String getRootDir()

Description copied from class: StateStoreFileBaseImpl

Get root directory.

Specified by:

getRootDir in class StateStoreFileBaseImpl

Returns:

Root directory.

getConcurrentFilesAccessNumThreads

protected int getConcurrentFilesAccessNumThreads()

Specified by:

getConcurrentFilesAccessNumThreads in class StateStoreFileBaseImpl

close

public void close()
           throws Exception

Description copied from class: StateStoreDriver

Close the State Store driver connection.

Overrides:

close in class StateStoreFileBaseImpl

Throws:

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

getReader

protected <T extends BaseRecord> BufferedReader getReader(String pathName)

Description copied from class: StateStoreFileBaseImpl

Get the reader of a record for the file system.

Specified by:

getReader in class StateStoreFileBaseImpl

Type Parameters:

T - Type of the state store record.

Parameters:

pathName - Path of the record to read.

Returns:

Reader for the record.

getWriter

@VisibleForTesting
public <T extends BaseRecord> BufferedWriter getWriter(String pathName)

Description copied from class: StateStoreFileBaseImpl

Get the writer of a record for the file system.

Specified by:

getWriter in class StateStoreFileBaseImpl

Type Parameters:

T - Type of the state store record.

Parameters:

pathName - Path of the record to write.

Returns:

Writer for the record.

getChildren

protected List<String> getChildren(String pathName)

Description copied from class: StateStoreFileBaseImpl

Get the children for a path.

Specified by:

getChildren in class StateStoreFileBaseImpl

Parameters:

pathName - Path to check.

Returns:

List of children.