Package org.springframework.integration.jdbc.store

Class JdbcChannelMessageStore

java.lang.Object

org.springframework.integration.jdbc.store.JdbcChannelMessageStore

All Implemented Interfaces:

InitializingBean, BasicMessageGroupStore, ChannelMessageStore, PriorityCapableChannelMessageStore

@ManagedResource
public class JdbcChannelMessageStore
extends Object
implements PriorityCapableChannelMessageStore, InitializingBean

Channel-specific implementation of MessageGroupStore using a relational database via JDBC. This message store shall be used for message channels only.

As such, the JdbcChannelMessageStore uses database specific SQL queries.

Contrary to the JdbcMessageStore, this implementation uses a single database table, optimized to operate like a queue. The SQL scripts for creating the table are packaged under org/springframework/integration/jdbc/schema-*.sql, where * denotes the target database type.

Since:

2.2

Author:

Gunnar Hillert, Artem Bilan, Gary Russell, Meherzad Lahewala

Field Summary

Fields

Modifier and Type	Field	Description
static String	DEFAULT_REGION	Default region property, used to partition the message store.
static String	DEFAULT_TABLE_PREFIX	Default value for the table prefix property.

Constructor Summary

Constructors

Constructor	Description
JdbcChannelMessageStore()	Convenient constructor for configuration use.
JdbcChannelMessageStore(DataSource dataSource)	Create a MessageStore with all mandatory properties.

Method Summary

Modifier and Type	Method	Description
void	addAllowedPatterns(String... patterns)	Add patterns for packages/classes that are allowed to be deserialized.
MessageGroup	addMessageToGroup(Object groupId, Message<?> message)	Store a message in the database.
void	afterPropertiesSet()	Check mandatory properties (DataSource and setChannelMessageStoreQueryProvider(ChannelMessageStoreQueryProvider)).
protected Message<?>	doPollForMessage(String groupIdKey)	This method executes a call to the DB to get the oldest Message in the MessageGroup which in the context of the JdbcChannelMessageStore means the channel identifier.
MessageGroup	getMessageGroup(Object groupId)	Not fully used.
int	getMessageGroupCount()	Method not implemented.
protected MessageGroupFactory	getMessageGroupFactory()
protected String	getQuery(org.springframework.integration.jdbc.store.JdbcChannelMessageStore.Query queryName, Supplier<String> queryProvider)	Replace patterns in the input to produce a valid SQL query.
int	getSizeOfIdCache()	Returns the size of the Message Id Cache, which caches Message Ids for those messages that are currently being processed.
boolean	isPriorityEnabled()
int	messageGroupSize(Object groupId)	Returns the number of messages persisted for the specified channel id (groupId) and the specified region (setRegion(String)).
Message<?>	pollMessageFromGroup(Object groupId)	Polls the database for a new message that is persisted for the given group id which represents the channel identifier.
void	removeFromIdCache(String messageId)	Remove a Message Id from the idCache.
void	removeMessageGroup(Object groupId)	Remove the message group with this id.
void	setChannelMessageStoreQueryProvider(ChannelMessageStoreQueryProvider channelMessageStoreQueryProvider)	Sets the database specific ChannelMessageStoreQueryProvider to use.
void	setDataSource(DataSource dataSource)	The JDBC DataSource to use when interacting with the database.
void	setDeserializer(Deserializer<? extends Message<?>> deserializer)	A converter for deserializing byte arrays to messages.
void	setJdbcTemplate(JdbcTemplate jdbcTemplate)	The JdbcOperations to use when interacting with the database.
void	setLobHandler(LobHandler lobHandler)	Override the LobHandler that is used to create and unpack large objects in SQL queries.
void	setMessageGroupFactory(MessageGroupFactory messageGroupFactory)	Specify the MessageGroupFactory to create MessageGroup object where it is necessary.
void	setMessageRowMapper(MessageRowMapper messageRowMapper)	Allows for passing in a custom MessageRowMapper.
void	setPreparedStatementSetter(ChannelMessageStorePreparedStatementSetter preparedStatementSetter)	Set a ChannelMessageStorePreparedStatementSetter to insert message into the database.
void	setPriorityEnabled(boolean priorityEnabled)
void	setRegion(String region)	A unique grouping identifier for all messages persisted with this store.
void	setSerializer(Serializer<? super Message<?>> serializer)	A converter for serializing messages to byte arrays for storage.
void	setTablePrefix(String tablePrefix)	Public setter for the table prefix property.
void	setUsingIdCache(boolean usingIdCache)	Consider using this property when polling the database transactionally using multiple parallel threads, meaning when the configured poller is configured using a task executor.

Methods inherited from class java.lang.Object

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

Field Details

DEFAULT_REGION

public static final String DEFAULT_REGION

Default region property, used to partition the message store. For example, a separate Spring Integration application with overlapping channel names may use the same message store by providing a distinct region name.

See Also:

Constant Field Values

DEFAULT_TABLE_PREFIX

public static final String DEFAULT_TABLE_PREFIX

Default value for the table prefix property.

See Also:

Constant Field Values

Constructor Details

JdbcChannelMessageStore

public JdbcChannelMessageStore()

Convenient constructor for configuration use.

JdbcChannelMessageStore

public JdbcChannelMessageStore(DataSource dataSource)

Create a MessageStore with all mandatory properties. The passed-in DataSource is used to instantiate a JdbcTemplate with JdbcTemplate.setFetchSize(int) set to 1 and with JdbcTemplate.setMaxRows(int) set to 1.

Parameters:

dataSource - a DataSource

Method Details

setDataSource

public void setDataSource(DataSource dataSource)

The JDBC DataSource to use when interacting with the database. The passed-in DataSource is used to instantiate a JdbcTemplate with JdbcTemplate.setFetchSize(int) set to 1 and with JdbcTemplate.setMaxRows(int) set to 1.

Parameters:

dataSource - a DataSource

setDeserializer

public void setDeserializer(Deserializer<? extends Message<?>> deserializer)

A converter for deserializing byte arrays to messages.

Parameters:

deserializer - the deserializer to set

addAllowedPatterns

public void addAllowedPatterns(String... patterns)

Add patterns for packages/classes that are allowed to be deserialized. A class can be fully qualified or a wildcard '*' is allowed at the beginning or end of the class name. Examples: com.foo.*, *.MyClass.

Parameters:

patterns - the patterns.

Since:

5.4

setJdbcTemplate

public void setJdbcTemplate(JdbcTemplate jdbcTemplate)

The JdbcOperations to use when interacting with the database. Either this property can be set or the dataSource. Please consider passing in a JdbcTemplate with a fetchSize property of 1. This is particularly important for Oracle to ensure First In, First Out (FIFO) message retrieval characteristics.

Parameters:

jdbcTemplate - a JdbcOperations

setLobHandler

public void setLobHandler(LobHandler lobHandler)

Override the LobHandler that is used to create and unpack large objects in SQL queries. The default is fine for almost all platforms, but some Oracle drivers require a native implementation.

Parameters:

lobHandler - a LobHandler

setMessageRowMapper

public void setMessageRowMapper(MessageRowMapper messageRowMapper)

Allows for passing in a custom MessageRowMapper. The MessageRowMapper is used to convert the selected database row representing the persisted message into the actual Message object.

Parameters:

messageRowMapper - Must not be null

setPreparedStatementSetter

public void setPreparedStatementSetter(ChannelMessageStorePreparedStatementSetter preparedStatementSetter)

Set a ChannelMessageStorePreparedStatementSetter to insert message into the database.

Parameters:

preparedStatementSetter - ChannelMessageStorePreparedStatementSetter to use. Must not be null

Since:

5.0

setChannelMessageStoreQueryProvider

public void setChannelMessageStoreQueryProvider(ChannelMessageStoreQueryProvider channelMessageStoreQueryProvider)

Sets the database specific ChannelMessageStoreQueryProvider to use. The JdbcChannelMessageStore provides the SQL queries to retrieve messages from the database. See the JavaDocs ChannelMessageStoreQueryProvider (all known implementing classes) to see those implementations provided by the framework.

You can provide your own query implementations, if you need to support additional databases and/or need to fine-tune the queries for your requirements.

Parameters:

channelMessageStoreQueryProvider - Must not be null.

setRegion

public void setRegion(String region)

A unique grouping identifier for all messages persisted with this store. Using multiple regions allows the store to be partitioned (if necessary) for different purposes. Defaults to DEFAULT_REGION.

Parameters:

region - the region name to set

setSerializer

public void setSerializer(Serializer<? super Message<?>> serializer)

A converter for serializing messages to byte arrays for storage.

Parameters:

serializer - The serializer to set

setTablePrefix

public void setTablePrefix(String tablePrefix)

Public setter for the table prefix property. This will be prefixed to all the table names before queries are executed. Defaults to DEFAULT_TABLE_PREFIX.

Parameters:

tablePrefix - the tablePrefix to set

setUsingIdCache

public void setUsingIdCache(boolean usingIdCache)

Consider using this property when polling the database transactionally using multiple parallel threads, meaning when the configured poller is configured using a task executor.

The issue is that the pollMessageFromGroup(Object) looks for the oldest entry for a giving channel (groupKey) and region (setRegion(String)). If you do that with multiple threads and you are using transactions, other threads may be waiting for that same locked row.

If using the provided OracleChannelMessageStoreQueryProvider, don't set usingIdCache to true, as the Oracle query will ignore locked rows.

Using the id cache, the JdbcChannelMessageStore will store each message id in an in-memory collection for the duration of processing. With that, any polling threads will explicitly exclude those messages from being polled.

For this to work, you must setup the corresponding TransactionSynchronizationFactory:

 
 <int:transaction-synchronization-factory id="syncFactory">
     <int:after-commit   expression="@jdbcChannelMessageStore.removeFromIdCache(headers.id.toString())" />
     <int:after-rollback expression="@jdbcChannelMessageStore.removeFromIdCache(headers.id.toString())" />
 </int:transaction-synchronization-factory>
 
 

This TransactionSynchronizationFactory is then referenced in the transaction configuration of the poller:

 
 <int:poller fixed-delay="300" receive-timeout="500"
     max-messages-per-poll="1" task-executor="pool">
     <int:transactional propagation="REQUIRED" synchronization-factory="syncFactory"
         isolation="READ_COMMITTED" transaction-manager="transactionManager" />
 </int:poller>
 
 

Parameters:

usingIdCache - When true the id cache will be used.

setPriorityEnabled

public void setPriorityEnabled(boolean priorityEnabled)

isPriorityEnabled

public boolean isPriorityEnabled()

Specified by:

isPriorityEnabled in interface PriorityCapableChannelMessageStore

Returns:

true if message priority is enabled in this channel message store.

setMessageGroupFactory

public void setMessageGroupFactory(MessageGroupFactory messageGroupFactory)

Specify the MessageGroupFactory to create MessageGroup object where it is necessary. Defaults to SimpleMessageGroupFactory.

Parameters:

messageGroupFactory - the MessageGroupFactory to use.

Since:

4.3

getMessageGroupFactory

protected MessageGroupFactory getMessageGroupFactory()

afterPropertiesSet

public void afterPropertiesSet()

Check mandatory properties (DataSource and setChannelMessageStoreQueryProvider(ChannelMessageStoreQueryProvider)). If no MessageRowMapper and ChannelMessageStorePreparedStatementSetter was explicitly set using setMessageRowMapper(MessageRowMapper) and setPreparedStatementSetter(ChannelMessageStorePreparedStatementSetter) respectively, the default MessageRowMapper and ChannelMessageStorePreparedStatementSetter will be instantiate using the specified deserializer and lobHandler. Also, if the jdbcTemplate's fetchSize property (JdbcTemplate.getFetchSize()) is not 1, a warning will be logged. When using the JdbcChannelMessageStore with Oracle, the fetchSize value of 1 is needed to ensure FIFO characteristics of polled messages. Please see the Oracle ChannelMessageStoreQueryProvider for more details.

Specified by:

afterPropertiesSet in interface InitializingBean

addMessageToGroup

public MessageGroup addMessageToGroup(Object groupId, Message<?> message)

Store a message in the database. The groupId identifies the channel for which the message is to be stored. Keep in mind that the actual groupId (Channel Identifier) is converted to a String-based UUID identifier.

Specified by:

addMessageToGroup in interface BasicMessageGroupStore

Parameters:

groupId - the group id to store the message under

message - a message

Returns:

The message group.

getMessageGroup

public MessageGroup getMessageGroup(Object groupId)

Not fully used. Only wraps the provided group id.

Specified by:

getMessageGroup in interface BasicMessageGroupStore

Parameters:

groupId - The group identifier.

Returns:

A group of messages, empty if none exists for this key.

getMessageGroupCount

@ManagedAttribute public int getMessageGroupCount()

Method not implemented.

Returns:

The message group count.

Throws:

UnsupportedOperationException - Method not supported.

getQuery

protected String getQuery(org.springframework.integration.jdbc.store.JdbcChannelMessageStore.Query queryName, Supplier<String> queryProvider)

Replace patterns in the input to produce a valid SQL query. This implementation lazily initializes a simple map-based cache, only replacing the table prefix on the first access to a named query. Further accesses will be resolved from the cache.

Parameters:

queryName - The JdbcChannelMessageStore.Query to be transformed.

queryProvider - a supplier to provide the query template.

Returns:

A transformed query with replacements.

messageGroupSize

@ManagedAttribute public int messageGroupSize(Object groupId)

Returns the number of messages persisted for the specified channel id (groupId) and the specified region (setRegion(String)).

Specified by:

messageGroupSize in interface BasicMessageGroupStore

Parameters:

groupId - The group identifier.

Returns:

The message group size.

removeMessageGroup

public void removeMessageGroup(Object groupId)

Description copied from interface: BasicMessageGroupStore

Remove the message group with this id.

Specified by:

removeMessageGroup in interface BasicMessageGroupStore

Parameters:

groupId - The id of the group to remove.

pollMessageFromGroup

public Message<?> pollMessageFromGroup(Object groupId)

Polls the database for a new message that is persisted for the given group id which represents the channel identifier.

Specified by:

pollMessageFromGroup in interface BasicMessageGroupStore

Parameters:

groupId - The group identifier.

Returns:

The message.

doPollForMessage

protected Message<?> doPollForMessage(String groupIdKey)

This method executes a call to the DB to get the oldest Message in the MessageGroup which in the context of the JdbcChannelMessageStore means the channel identifier.

Parameters:

groupIdKey - String representation of message group (Channel) ID

Returns:

a message; could be null if query produced no Messages

removeFromIdCache

public void removeFromIdCache(String messageId)

Remove a Message Id from the idCache. Should be used in conjunction with the Spring Integration Transaction Synchronization feature to remove a message from the Message Id cache once a transaction either succeeded or rolled back.

Only applicable if setUsingIdCache(boolean) is set to true

.

Parameters:

messageId - The message identifier.

getSizeOfIdCache

@ManagedMetric public int getSizeOfIdCache()

Returns the size of the Message Id Cache, which caches Message Ids for those messages that are currently being processed.

Returns:

The size of the Message Id Cache