Ehcache Component

Table of Contents

URI format
Options
Ehcache based idempotent repository example:
Ehcache based aggregation repository example:

Available as of Camel 2.18.x

The ehcache component enables you to perform caching operations using Ehcache 3 as the Cache Implementation.

This component supports producer and event based consumer endpoints.

The Cache consumer is an event based consumer and can be used to listen and respond to specific cache activities.

Maven users will need to add the following dependency to their pom.xml for this component:

<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-ehcache</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

URI format

ehcache://cacheName[?options]

You can append query options to the URI in the following format, ?option=value&option=#beanRef&…

Options

Table of Contents

Message Headers Camel

The Ehcache component has no options.

The Ehcache component supports 5 endpoint options which are listed below:

{% raw %}

Name	Group	Default	Java Type	Description
cacheName	common		`String`	Required the cache name
bridgeErrorHandler	consumer	`false`	`boolean`	Allows for bridging the consumer to the Camel routing Error Handler which mean any exceptions occurred while the consumer is trying to pickup incoming messages or the likes will now be processed as a message and handled by the routing Error Handler. By default the consumer will use the org.apache.camel.spi.ExceptionHandler to deal with exceptions that will be logged at WARN/ERROR level and ignored.
exceptionHandler	consumer (advanced)		`ExceptionHandler`	To let the consumer use a custom ExceptionHandler. Notice if the option bridgeErrorHandler is enabled then this options is not in use. By default the consumer will deal with exceptions that will be logged at WARN/ERROR level and ignored.
exchangePattern	consumer (advanced)		`ExchangePattern`	Sets the exchange pattern when the consumer creates an exchange.
synchronous	advanced	`false`	`boolean`	Sets whether synchronous processing should be strictly used or Camel is allowed to use asynchronous processing (if supported).

{% endraw %}

Message Headers Camel

Header	Type	Description
CamelEhcacheAction	`String`	The operation to be perfomed on the cache, valid options are: * CLEAR * PUT * PUT_ALL * PUT_IF_ABSENT * GET * GET_ALL * REMOVE * REMOVE_ALL * REPLACE
CamelEhcacheActionHasResult	Boolean	Set to true if the action has a result
CamelEhcacheActionSucceeded	`Boolean`	Set to true if the actionsuccedded
CamelEhcacheKey	Object	The cache key used for an action
CamelEhcacheKeys	Set<Object>	A list of keys, used in * PUT_ALL * GET_ALL * REMOVE_ALL
CamelEhcacheValue	Object	The value to put in the cache or the result of an operation
CamelEhcacheOldValue	Object	The old value associated to a key for actions like PUT_IF_ABSENT or the Object used for comparison for actions like REPLACE
CamelEhcacheEventType	EventType	The type of event received

Ehcache based idempotent repository example:

CacheManager manager = CacheManagerBuilder.newCacheManager(new XmlConfiguration("ehcache.xml"));
EhcacheIdempotentRepository repo = new EhcacheIdempotentRepository(manager, "idempotent-cache");

from("direct:in")
    .idempotentConsumer(header("messageId"), idempotentRepo)
    .to("mock:out");

Ehcache based aggregation repository example:

public class EhcacheAggregationRepositoryRoutesTest extends CamelTestSupport {
    private static final String ENDPOINT_MOCK = "mock:result";
    private static final String ENDPOINT_DIRECT = "direct:one";
    private static final int[] VALUES = generateRandomArrayOfInt(10, 0, 30);
    private static final int SUM = IntStream.of(VALUES).reduce(0, (a, b) -> a + b);
    private static final String CORRELATOR = "CORRELATOR";

    @EndpointInject(uri = ENDPOINT_MOCK)
    private MockEndpoint mock;

    @Produce(uri = ENDPOINT_DIRECT)
    private ProducerTemplate producer;

    @Test
    public void checkAggregationFromOneRoute() throws Exception {
        mock.expectedMessageCount(VALUES.length);
        mock.expectedBodiesReceived(SUM);

        IntStream.of(VALUES).forEach(
            i -> producer.sendBodyAndHeader(i, CORRELATOR, CORRELATOR)
        );

        mock.assertIsSatisfied();
    }

    private Exchange aggregate(Exchange oldExchange, Exchange newExchange) {
        if (oldExchange == null) {
            return newExchange;
        } else {
            Integer n = newExchange.getIn().getBody(Integer.class);
            Integer o = oldExchange.getIn().getBody(Integer.class);
            Integer v = (o == null ? 0 : o) + (n == null ? 0 : n);

            oldExchange.getIn().setBody(v, Integer.class);

            return oldExchange;
        }
    }

    @Override
    protected RoutesBuilder createRouteBuilder() throws Exception {
        return new RouteBuilder() {
            @Override
            public void configure() throws Exception {
                from(ENDPOINT_DIRECT)
                    .routeId("AggregatingRouteOne")
                    .aggregate(header(CORRELATOR))
                    .aggregationRepository(createAggregateRepository())
                    .aggregationStrategy(EhcacheAggregationRepositoryRoutesTest.this::aggregate)
                    .completionSize(VALUES.length)
                        .to("log:org.apache.camel.component.ehcache.processor.aggregate.level=INFO&showAll=true&mulltiline=true")
                        .to(ENDPOINT_MOCK);
            }
        };
    }

    protected EhcacheAggregationRepository createAggregateRepository() throws Exception {
        CacheManager cacheManager = CacheManagerBuilder.newCacheManager(new XmlConfiguration("ehcache.xml"));
        cacheManager.init();

        EhcacheAggregationRepository repository = new EhcacheAggregationRepository();
        repository.setCacheManager(cacheManager);
        repository.setCacheName("aggregate");

        return repository;
    }
}