Package org.apache.bookkeeper.meta

Class ZkLedgerIdGenerator

java.lang.Object

org.apache.bookkeeper.meta.ZkLedgerIdGenerator

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable, LedgerIdGenerator

public class ZkLedgerIdGenerator
extends java.lang.Object
implements LedgerIdGenerator

ZooKeeper based ledger id generator class, which using EPHEMERAL_SEQUENTIAL with (ledgerIdGenPath)/ID- prefix to generate ledger id. Note zookeeper sequential counter has a format of %10d -- that is 10 digits with 0 (zero) padding, i.e. "<path>0000000001", so ledger id space is fundamentally limited to 9 billion.

Field Summary

Fields

Modifier and Type	Field	Description
(package private) static java.lang.String	LEDGER_ID_GEN_PREFIX
(package private) java.lang.String	ledgerPrefix
(package private) static org.slf4j.Logger	LOG
(package private) org.apache.zookeeper.ZooKeeper	zk
(package private) java.util.List<org.apache.zookeeper.data.ACL>	zkAcls

Constructor Summary

Constructors

Constructor	Description
ZkLedgerIdGenerator(org.apache.zookeeper.ZooKeeper zk, java.lang.String ledgersPath, java.lang.String idGenZnodeName, java.util.List<org.apache.zookeeper.data.ACL> zkAcls)

Method Summary

Modifier and Type	Method	Description
void	close()
static java.lang.String	createLedgerPrefix(java.lang.String ledgersPath, java.lang.String idGenZnodeName)
void	generateLedgerId(BookkeeperInternalCallbacks.GenericCallback<java.lang.Long> cb)	Generate a global unique ledger id.
static void	generateLedgerIdImpl(BookkeeperInternalCallbacks.GenericCallback<java.lang.Long> cb, org.apache.zookeeper.ZooKeeper zk, java.lang.String ledgerPrefix, java.util.List<org.apache.zookeeper.data.ACL> zkAcls)

Methods inherited from class java.lang.Object

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

Field Detail

LOG

static final org.slf4j.Logger LOG

LEDGER_ID_GEN_PREFIX

static final java.lang.String LEDGER_ID_GEN_PREFIX

See Also:

Constant Field Values

zk

final org.apache.zookeeper.ZooKeeper zk

ledgerPrefix

final java.lang.String ledgerPrefix

zkAcls

final java.util.List<org.apache.zookeeper.data.ACL> zkAcls

Constructor Detail

ZkLedgerIdGenerator

public ZkLedgerIdGenerator(org.apache.zookeeper.ZooKeeper zk,
                           java.lang.String ledgersPath,
                           java.lang.String idGenZnodeName,
                           java.util.List<org.apache.zookeeper.data.ACL> zkAcls)

Method Detail

createLedgerPrefix

public static java.lang.String createLedgerPrefix(java.lang.String ledgersPath,
                                                  java.lang.String idGenZnodeName)

generateLedgerId

public void generateLedgerId(BookkeeperInternalCallbacks.GenericCallback<java.lang.Long> cb)

Description copied from interface: LedgerIdGenerator

Generate a global unique ledger id.

Specified by:

generateLedgerId in interface LedgerIdGenerator

Parameters:

cb - Callback when a new ledger id is generated, return code:

• BKException.Code.OK if success
• BKException.Code.ZKException when can't generate new ledger id

generateLedgerIdImpl

public static void generateLedgerIdImpl(BookkeeperInternalCallbacks.GenericCallback<java.lang.Long> cb,
                                        org.apache.zookeeper.ZooKeeper zk,
                                        java.lang.String ledgerPrefix,
                                        java.util.List<org.apache.zookeeper.data.ACL> zkAcls)

close

public void close()
           throws java.io.IOException

Specified by:

close in interface java.lang.AutoCloseable

Specified by:

close in interface java.io.Closeable

Throws:

java.io.IOException