org.neo4j.helpers

Class TransactionTemplate

java.lang.Object

org.neo4j.helpers.TransactionTemplate

public class TransactionTemplate
extends Object

Neo4j transaction template that automates the retry-on-exception logic. It uses the builder pattern for configuration, with copy-semantics, so you can iteratively build up instances for different scenarios.

First instantiate and configure the template using the fluent API methods, and then invoke execute which will begin/commit transactions in a loop for the specified number of times.

By default all exceptions (except Errors and TransactionTerminatedException) cause a retry, and the monitor does nothing, but these can be overridden with custom behavior. A bit more narrow and typical exception to retry on is TransientFailureException, which aims to represent exceptions that are most likely to succeed after a retry.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	TransactionTemplate.Monitor

Constructor Summary

Constructors

Constructor and Description
TransactionTemplate()
TransactionTemplate(org.neo4j.graphdb.GraphDatabaseService gds, TransactionTemplate.Monitor monitor, int retries, long backoff, Predicate<Throwable> retryPredicate)

Method Summary

Modifier and Type	Method and Description
TransactionTemplate	backoff(long backoff, TimeUnit unit)
void	execute(Consumer<org.neo4j.graphdb.Transaction> txConsumer)
<T> T	execute(Function<org.neo4j.graphdb.Transaction,T> txFunction)
TransactionTemplate	monitor(TransactionTemplate.Monitor monitor)
TransactionTemplate	retries(int retries)
TransactionTemplate	retryOn(Predicate<Throwable> retryPredicate)
TransactionTemplate	with(org.neo4j.graphdb.GraphDatabaseService gds)

Methods inherited from class java.lang.Object

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

Constructor Detail

TransactionTemplate

public TransactionTemplate()

TransactionTemplate

public TransactionTemplate(org.neo4j.graphdb.GraphDatabaseService gds,
                           TransactionTemplate.Monitor monitor,
                           int retries,
                           long backoff,
                           Predicate<Throwable> retryPredicate)

Method Detail

with

public TransactionTemplate with(org.neo4j.graphdb.GraphDatabaseService gds)

retries

public TransactionTemplate retries(int retries)

backoff

public TransactionTemplate backoff(long backoff,
                                   TimeUnit unit)

monitor

public TransactionTemplate monitor(TransactionTemplate.Monitor monitor)

retryOn

public TransactionTemplate retryOn(Predicate<Throwable> retryPredicate)

execute

public void execute(Consumer<org.neo4j.graphdb.Transaction> txConsumer)

execute

public <T> T execute(Function<org.neo4j.graphdb.Transaction,T> txFunction)
              throws org.neo4j.graphdb.TransactionFailureException

Throws:

org.neo4j.graphdb.TransactionFailureException