org.springframework.integration.r2dbc.inbound

Class R2dbcMessageSource

java.lang.Object

org.springframework.integration.util.AbstractExpressionEvaluator

org.springframework.integration.endpoint.AbstractMessageSource<org.reactivestreams.Publisher<?>>

org.springframework.integration.r2dbc.inbound.R2dbcMessageSource

All Implemented Interfaces:

Aware, BeanFactoryAware, BeanNameAware, DisposableBean, InitializingBean, MessageSource<org.reactivestreams.Publisher<?>>, IntegrationPattern, NamedComponent, IntegrationInboundManagement, IntegrationManagement

public class R2dbcMessageSource
extends AbstractMessageSource<org.reactivestreams.Publisher<?>>

An instance of MessageSource which returns a Message with a payload which is the result of execution of query. When expectSingleResult is false (default), the R2DBC query is executed returning a Flux. The returned Flux will be used as the payload of the Message returned by the AbstractMessageSource.receive() method.

When expectSingleResult is true, the query is executed returning a Mono for the single object returned from the query.

Since:

5.4

Author:

Rohan Mukesh, Artem Bilan

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
class	R2dbcMessageSource.SelectCreator An instance of this class is used as a root object for query expression to give a limited access only to the StatementMapper.createSelect(java.lang.String) fluent API.

Nested classes/interfaces inherited from interface org.springframework.integration.support.management.IntegrationManagement

IntegrationManagement.ManagementOverrides

Field Summary

Fields inherited from class org.springframework.integration.util.AbstractExpressionEvaluator

EXPRESSION_PARSER, logger

Fields inherited from interface org.springframework.integration.support.management.IntegrationManagement

METER_PREFIX, RECEIVE_COUNTER_NAME, SEND_TIMER_NAME

Constructor Summary

Constructors

Constructor and Description
R2dbcMessageSource(org.springframework.data.r2dbc.core.R2dbcEntityOperations r2dbcEntityOperations, Expression queryExpression) Create an instance with the provided R2dbcEntityOperations and SpEL expression which should resolve to a query string or StatementMapper.SelectSpec instance.
R2dbcMessageSource(org.springframework.data.r2dbc.core.R2dbcEntityOperations r2dbcEntityOperations, String query) Create an instance with the provided R2dbcEntityOperations and SpEL expression which should resolve to a Relational 'query' string.

Method Summary

Modifier and Type	Method and Description
protected Object	doReceive() Execute a query returning its results as the Message payload.
String	getComponentType()
protected void	onInit()
void	setBindFunction(java.util.function.BiFunction<DatabaseClient.GenericExecuteSpec,?,DatabaseClient.GenericExecuteSpec> bindFunction) Set a BiFunction which is used to bind parameters into the update query.
void	setExpectSingleResult(boolean expectSingleResult) The flag to manage which find* method to invoke on R2dbcEntityOperations.
void	setPayloadType(Class<?> payloadType) Set the type of the entityClass which is used for the EntityRowMapper.
void	setUpdateSql(String updateSql) Set an update query that will be passed to the DatabaseClient.sql(String) method.

Methods inherited from class org.springframework.integration.endpoint.AbstractMessageSource

buildMessage, destroy, getBeanName, getComponentName, getManagedName, getManagedType, getOverrides, isLoggingEnabled, receive, registerMetricsCaptor, setBeanName, setHeaderExpressions, setLoggingEnabled, setManagedName, setManagedType

Methods inherited from class org.springframework.integration.util.AbstractExpressionEvaluator

afterPropertiesSet, evaluateExpression, evaluateExpression, evaluateExpression, evaluateExpression, evaluateExpression, evaluateExpression, evaluateExpression, getBeanFactory, getEvaluationContext, getEvaluationContext, getMessageBuilderFactory, setBeanFactory, setConversionService

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.springframework.integration.core.MessageSource

getIntegrationPatternType

Methods inherited from interface org.springframework.integration.support.management.IntegrationManagement

getThisAs

Constructor Detail

R2dbcMessageSource

public R2dbcMessageSource(org.springframework.data.r2dbc.core.R2dbcEntityOperations r2dbcEntityOperations,
                          String query)

Create an instance with the provided R2dbcEntityOperations and SpEL expression which should resolve to a Relational 'query' string. It assumes that the R2dbcEntityOperations is fully initialized and ready to be used. The 'query' will be evaluated on every call to the AbstractMessageSource.receive() method.

Parameters:

r2dbcEntityOperations - The reactive database client for performing database calls.

query - The query String.

R2dbcMessageSource

public R2dbcMessageSource(org.springframework.data.r2dbc.core.R2dbcEntityOperations r2dbcEntityOperations,
                          Expression queryExpression)

Create an instance with the provided R2dbcEntityOperations and SpEL expression which should resolve to a query string or StatementMapper.SelectSpec instance. It assumes that the R2dbcEntityOperations is fully initialized and ready to be used. The 'queryExpression' will be evaluated on every call to the AbstractMessageSource.receive() method.

Parameters:

r2dbcEntityOperations - The reactive for performing database calls.

queryExpression - The query expression. The root object for evaluation context is a R2dbcMessageSource.SelectCreator for delegation int the StatementMapper.createSelect(java.lang.String) fluent API.

Method Detail

setPayloadType

public void setPayloadType(Class<?> payloadType)

Set the type of the entityClass which is used for the EntityRowMapper.

Parameters:

payloadType - The class to use.

setUpdateSql

public void setUpdateSql(String updateSql)

Set an update query that will be passed to the DatabaseClient.sql(String) method.

Parameters:

updateSql - the update query string.

setBindFunction

public void setBindFunction(java.util.function.BiFunction<DatabaseClient.GenericExecuteSpec,?,DatabaseClient.GenericExecuteSpec> bindFunction)

Set a BiFunction which is used to bind parameters into the update query.

Parameters:

bindFunction - the BiFunction to use.

setExpectSingleResult

public void setExpectSingleResult(boolean expectSingleResult)

The flag to manage which find* method to invoke on R2dbcEntityOperations. Default is 'false', which means the AbstractMessageSource.receive() method will use the DatabaseClient.sql(String) method and will fetch all. If set to 'true'AbstractMessageSource.receive() will use DatabaseClient.sql(String) and will fetch one and the payload of the returned Message will be the returned target Object of type identified by payloadType instead of a List.

Parameters:

expectSingleResult - true if a single result is expected.

getComponentType

public String getComponentType()

onInit

protected void onInit()

Overrides:

onInit in class AbstractExpressionEvaluator

doReceive

protected Object doReceive()

Execute a query returning its results as the Message payload. The payload can be either Flux or Mono of objects of type identified by payloadType, or a single element of type identified by payloadType based on the value of expectSingleResult attribute which defaults to 'false' resulting Message with payload of type Flux.

Specified by:

doReceive in class AbstractMessageSource<org.reactivestreams.Publisher<?>>

Returns:

The value returned.