Package com.github.ddth.queue.impl.universal

Class BaseUniversalJdbcQueue<T extends BaseUniversalQueueMessage<ID>,ID>

java.lang.Object

com.github.ddth.queue.impl.AbstractQueue<ID,DATA>

com.github.ddth.queue.impl.AbstractEphemeralSupportQueue<ID,DATA>

com.github.ddth.queue.impl.JdbcQueue<ID,byte[]>

com.github.ddth.queue.impl.universal.BaseUniversalJdbcQueue<T,ID>

Type Parameters:

T -

All Implemented Interfaces:

IQueue<ID,byte[]>, AutoCloseable

Direct Known Subclasses:

BaseLessLockingUniversalJdbcQueue, BaseLessLockingUniversalSingleStorageJdbcQueue, UniversalJdbcQueue, UniversalJdbcQueue, UniversalSingleStorageJdbcQueue, UniversalSingleStorageJdbcQueue

public abstract class BaseUniversalJdbcQueue<T extends BaseUniversalQueueMessage<ID>,ID>
extends JdbcQueue<ID,byte[]>

Base class for universal JDBC queue implementations.

FIFO: if true, queue message with lower id is ensured to be taken first; if false, order of taken queue messages depends on the DBMS (usually FIFO in most cases).

Since:

0.6.0

Author:

Thanh Nguyen

Nested Class Summary

Nested classes/interfaces inherited from class com.github.ddth.queue.impl.AbstractQueue

AbstractQueue.PutToQueueCase

Field Summary

Fields inherited from class com.github.ddth.queue.impl.JdbcQueue

DEFAULT_MAX_RETRIES, DEFAULT_TRANX_ISOLATION_LEVEL

Fields inherited from interface com.github.ddth.queue.IQueue

SIZE_NOT_SUPPORTED

Constructor Summary

Constructors

Constructor	Description
BaseUniversalJdbcQueue()

Method Summary

Modifier and Type	Method	Description
protected T	createMessge(Map<String,Object> data)	Create a message object from input data.
protected <X> X	ensureMessageType(IQueueMessage<ID,byte[]> msg, Class<X> msgClass)	Throw IllegalArgumentException if msg argument is not of type specified by msgClass.
boolean	getFifo()	Alias of isFifo().
boolean	isFifo()	If true, queue message with lower id is ensured to be taken first.
BaseUniversalJdbcQueue<T,ID>	markFifo(boolean fifo)	When set to true, queue message with lower id is ensured to be taken first.
protected List<T>	selectMessages(Connection conn, String sql, Map<String,Object> params)	Convenient method to query list of messages.
BaseUniversalJdbcQueue<T,ID>	setFifo(boolean fifo)	Alias of markFifo(boolean).
T	take()	Take a message out of queue.

Methods inherited from class com.github.ddth.queue.impl.JdbcQueue

_finishWithRetries, _getOrphanMessagesWithRetries, _queueWithRetries, _requeueSilentWithRetries, _requeueWithRetries, _takeWithRetries, buildJdbcHelper, destroy, doPutToQueue, doSize, ephemeralSize, ephemeralSize, executeWithRetries, executeWithRetries, executeWithRetries, finish, getDataSource, getJdbcHelper, getMaxRetries, getOrphanMessages, getOrphanMessagesFromEphemeralStorage, getTableName, getTableNameEphemeral, getTransactionIsolationLevel, init, peekFromQueueStorage, putToEphemeralStorage, putToQueueStorage, queueSize, queueSize, readFromEphemeralStorage, readFromEphemeralStorage, removeFromEphemeralStorage, removeFromQueueStorage, setDataSource, setJdbcHelper, setJdbcHelper, setMaxRetries, setTableName, setTableNameEphemeral, setTransactionIsolationLevel

Methods inherited from class com.github.ddth.queue.impl.AbstractEphemeralSupportQueue

getEphemeralDisabled, getEphemeralMaxSize, isEphemeralDisabled, setEphemeralDisabled, setEphemeralMaxSize

Methods inherited from class com.github.ddth.queue.impl.AbstractQueue

close, createMessage, createMessage, createMessage, deserialize, deserialize, getMessageFactory, getQueueName, getSerDeser, queue, requeue, requeueSilent, serialize, setMessageFactory, setQueueName, setSerDeser

Methods inherited from class java.lang.Object

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

Constructor Detail

BaseUniversalJdbcQueue

public BaseUniversalJdbcQueue()

Method Detail

markFifo

public BaseUniversalJdbcQueue<T,ID> markFifo(boolean fifo)

When set to true, queue message with lower id is ensured to be taken first. When set to false, order of taken queue messages depends on the DBMS (usually FIFO in most cases).

Parameters:

fifo -

Returns:

isFifo

public boolean isFifo()

If true, queue message with lower id is ensured to be taken first. Otherwise, order of taken queue messages depends on the DBMS (usually FIFO in most cases).

Returns:

setFifo

public BaseUniversalJdbcQueue<T,ID> setFifo(boolean fifo)

Alias of markFifo(boolean).

Parameters:

fifo -

Returns:

getFifo

public boolean getFifo()

Alias of isFifo().

Returns:

ensureMessageType

protected <X> X ensureMessageType(IQueueMessage<ID,byte[]> msg,
                                  Class<X> msgClass)

Throw IllegalArgumentException if msg argument is not of type specified by msgClass.

Type Parameters:

X -

Parameters:

msg -

msgClass -

Returns:

the msg casted to X

Since:

1.0.0

createMessge

protected T createMessge(Map<String,Object> data)

Create a message object from input data.

Parameters:

data -

Returns:

Since:

1.0.0

selectMessages

protected List<T> selectMessages(Connection conn,
                                 String sql,
                                 Map<String,Object> params)

Convenient method to query list of messages.

Parameters:

conn -

sql -

params -

Returns:

Since:

1.0.0

take

public T take()

Take a message out of queue.

Implementation flow:

• Read message from head of queue storage.
• Write message to ephemeral storage.
• Remove message from queue storage.

Note: ephemeral storage implementation is optional, depends on implementation.

Specified by:

take in interface IQueue<T extends BaseUniversalQueueMessage<ID>,ID>

Overrides:

take in class JdbcQueue<ID,byte[]>

Returns: