Chapter 85. LevelDB

public void configure() throws Exception {
    // create the leveldb repo
    LevelDBAggregationRepository repo = new LevelDBAggregationRepository("repo1", "target/data/leveldb.dat");

    // here is the Camel route where we aggregate
    from("direct:start")
        .aggregate(header("id"), new MyAggregationStrategy())
            // use our created leveldb repo as aggregation repository
            .completionSize(5).aggregationRepository(repo)
            .to("mock:aggregated");
}

<!-- a persistent aggregation repository using camel-leveldb -->
<bean id="repo" class="org.apache.camel.component.leveldb.LevelDBAggregationRepository">
    <!-- store the repo in the leveldb.dat file -->
    <property name="persistentFileName" value="target/data/leveldb.dat"/>
    <!-- and use repo2 as the repository name -->
    <property name="repositoryName" value="repo2"/>
</bean>

<!-- aggregate the messages using this strategy -->
<bean id="myAggregatorStrategy" class="org.apache.camel.component.leveldb.LevelDBSpringAggregateTest$MyAggregationStrategy"/>

<!-- this is the camel routes -->
<camelContext id="camel" xmlns="http://camel.apache.org/schema/spring">

    <route>
        <from uri="direct:start"/>
        <!-- aggregate using our strategy and leveldb repo, and complete when we have 5 messages aggregated -->
        <aggregate strategyRef="myAggregatorStrategy" aggregationRepositoryRef="repo" completionSize="5">
            <!-- correlate by header with the key id -->
            <correlationExpression><header>id</header></correlationExpression>
            <!-- send aggregated messages to the mock endpoint -->
            <to uri="mock:aggregated"/>
        </aggregate>
    </route>

</camelContext>

<dependency>
  <groupId>org.apache.camel</groupId>
  <artifactId>camel-leveldb</artifactId>
  <version>2.10.0</version>
</dependency>