org.kududb.client

Class KuduClient

java.lang.Object

org.kududb.client.KuduClient

All Implemented Interfaces:

AutoCloseable

@InterfaceAudience.Public
 @InterfaceStability.Evolving
public class KuduClient
extends Object
implements AutoCloseable

A synchronous and thread-safe client for Kudu.

This class acts as a wrapper around AsyncKuduClient. The Deferred objects are joined against using the default admin operation timeout (see KuduClient.KuduClientBuilder.defaultAdminOperationTimeoutMs(long) (long)}).

Field Summary

Fields

Modifier and Type	Field and Description
static org.slf4j.Logger	LOG

Method Summary

Modifier and Type	Method and Description
AlterTableResponse	alterTable(String name, AlterTableBuilder atb) Alter a table on the cluster as specified by the builder.
void	close() Analogous to shutdown().
KuduTable	createTable(String name, Schema schema) Create a table on the cluster with the specified name and schema.
KuduTable	createTable(String name, Schema schema, CreateTableBuilder builder) Create a table on the cluster with the specified name, schema, and table configurations.
DeleteTableResponse	deleteTable(String name) Delete a table on the cluster with the specified name.
long	getDefaultAdminOperationTimeoutMs() Get the timeout used for admin operations.
long	getDefaultOperationTimeoutMs() Get the timeout used for operations on sessions and scanners.
ListTablesResponse	getTablesList() Get the list of all the tables.
ListTablesResponse	getTablesList(String nameFilter) Get a list of table names.
boolean	isAlterTableDone(String name) Helper method that checks and waits until the completion of an alter command.
ListTabletServersResponse	listTabletServers() Get the list of running tablet servers.
KuduScanner.KuduScannerBuilder	newScannerBuilder(KuduTable table) Creates a new KuduScanner.KuduScannerBuilder for a particular table.
KuduSession	newSession() Create a new session for interacting with the cluster.
KuduTable	openTable(String name) Open the table with the given name.
void	shutdown() Performs a graceful shutdown of this instance.
boolean	tableExists(String name) Test if a table exists.

Methods inherited from class java.lang.Object

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

Field Detail

LOG

public static final org.slf4j.Logger LOG

Method Detail

createTable

public KuduTable createTable(String name,
                             Schema schema)
                      throws Exception

Create a table on the cluster with the specified name and schema. Default table configurations are used, mainly the table will have one tablet.

Parameters:

name - Table's name

schema - Table's schema

Returns:

an object to communicate with the created table

Throws:

Exception

createTable

public KuduTable createTable(String name,
                             Schema schema,
                             CreateTableBuilder builder)
                      throws Exception

Create a table on the cluster with the specified name, schema, and table configurations.

Parameters:

name - the table's name

schema - the table's schema

builder - a builder containing the table's configurations

Returns:

an object to communicate with the created table

Throws:

Exception

deleteTable

public DeleteTableResponse deleteTable(String name)
                                throws Exception

Delete a table on the cluster with the specified name.

Parameters:

name - the table's name

Returns:

an rpc response object

Throws:

Exception

alterTable

public AlterTableResponse alterTable(String name,
                                     AlterTableBuilder atb)
                              throws Exception

Alter a table on the cluster as specified by the builder. When the method returns it only indicates that the master accepted the alter command, use isAlterTableDone(String) to know when the alter finishes.

Parameters:

name - the table's name, if this is a table rename then the old table name must be passed

atb - the alter table builder

Returns:

an rpc response object

Throws:

Exception

isAlterTableDone

public boolean isAlterTableDone(String name)
                         throws Exception

Helper method that checks and waits until the completion of an alter command. It will block until the alter command is done or the timeout is reached.

Parameters:

name - Table's name, if the table was renamed then that name must be checked against

Returns:

a boolean indicating if the table is done being altered

Throws:

Exception

listTabletServers

public ListTabletServersResponse listTabletServers()
                                            throws Exception

Get the list of running tablet servers.

Returns:

a list of tablet servers

Throws:

Exception

getTablesList

public ListTablesResponse getTablesList()
                                 throws Exception

Get the list of all the tables.

Returns:

a list of all the tables

Throws:

Exception

getTablesList

public ListTablesResponse getTablesList(String nameFilter)
                                 throws Exception

Get a list of table names. Passing a null filter returns all the tables. When a filter is specified, it only returns tables that satisfy a substring match.

Parameters:

nameFilter - an optional table name filter

Returns:

a deferred that contains the list of table names

Throws:

Exception

tableExists

public boolean tableExists(String name)
                    throws Exception

Test if a table exists.

Parameters:

name - a non-null table name

Returns:

true if the table exists, else false

Throws:

Exception

openTable

public KuduTable openTable(String name)
                    throws Exception

Open the table with the given name. If the table was just created, this method will block until all its tablets have also been created.

Parameters:

name - table to open

Returns:

a KuduTable if the table exists, else a MasterErrorException

Throws:

Exception

newSession

public KuduSession newSession()

Create a new session for interacting with the cluster. User is responsible for destroying the session object. This is a fully local operation (no RPCs or blocking).

Returns:

a synchronous wrapper around KuduSession.

newScannerBuilder

public KuduScanner.KuduScannerBuilder newScannerBuilder(KuduTable table)

Creates a new KuduScanner.KuduScannerBuilder for a particular table.

Parameters:

table - the name of the table you intend to scan. The string is assumed to use the platform's default charset.

Returns:

a new scanner builder for this table

close

public void close()
           throws Exception

Analogous to shutdown().

Specified by:

close in interface AutoCloseable

Throws:

Exception - if an error happens while closing the connections

shutdown

public void shutdown()
              throws Exception

Performs a graceful shutdown of this instance.

Throws:

Exception

getDefaultOperationTimeoutMs

public long getDefaultOperationTimeoutMs()

Get the timeout used for operations on sessions and scanners.

Returns:

a timeout in milliseconds

getDefaultAdminOperationTimeoutMs

public long getDefaultAdminOperationTimeoutMs()

Get the timeout used for admin operations.

Returns:

a timeout in milliseconds