Configure Hazelcast in Spring

6.0-SNAPSHOT 5.5 5.4 5.3 5.2 5.1 5.0

This section describes how to set up Hazelcast in a new or existing Spring application.

Enable Spring integration

These instructions assume you are using Apache Maven. If you use another build system, you will need to adjust the definition of dependencies as required.

To enable Spring integration:

  1. Add hazelcast-spring-5.5.0.jar to your Java classpath.

  2. Add the following lines to your pom.xml file:

    <dependency>
    <groupId>com.hazelcast</groupId>
    <artifactId>hazelcast-spring</artifactId>
    <version>5.5.4</version>
</dependency>

  3. If you are an Enterprise customer and you want to use hazelcast-spring with hazelcast-enterprise, you also need to exclude the transitive hazelcast dependency:

    <dependency>
    <groupId>com.hazelcast</groupId>
    <artifactId>hazelcast-enterprise</artifactId>
    <version>5.5.4</version>
</dependency>
<dependency>
    <groupId>com.hazelcast</groupId>
    <artifactId>hazelcast-spring</artifactId>
    <version>5.5.4</version>
    <exclusions>
        <exclusion>
          <groupId>com.hazelcast</groupId>
          <artifactId>hazelcast</artifactId>
        </exclusion>
    </exclusions>
</dependency>

Troubleshooting

When the Spring integration JARs are not correctly installed in the Java classpath, you may see one of the following exceptions:

org.xml.sax.SAXParseException; systemId: http://hazelcast.com/schema/spring/hazelcast-spring.xsd; lineNumber: 2; columnNumber: 35; s4s-elt-character: Non-whitespace characters are not allowed in schema elements other than 'xs:appinfo' and 'xs:documentation'. Saw '301 Moved Permanently'.
org.springframework.beans.factory.parsing.BeanDefinitionParsingException: Configuration problem: Unable to locate Spring NamespaceHandler for XML schema namespace [http://www.hazelcast.com/schema/spring]
org.xml.sax.SAXParseException; lineNumber: 25; columnNumber: 33; schema_reference.4: Failed to read schema document 'http://www.hazelcast.com/schema/spring/hazelcast-spring.xsd', because 1) could not find the document; 2) the document could not be read; 3) the root element of the document is not <xsd:schema>.

If you see one of these exceptions, check that the required classes are in the classpath.

Declare beans using Java configuration

Spring recommend using Java-based configuration. The following example provides basic configuration for using Hazelcast in a Spring application:

import javax.management.MXBean;@Configuration(proxyBeanMethods = false)
public class SpringHazelcastConfiguration {

    @Bean
    public HazelcastInstance hazelcastInstance() { // (1)
        Config config = new Config();
        config.setClusterName("spring-hazelcast-cluster-from-java");

        NetworkConfig networkConfig = config.getNetworkConfig();
        networkConfig.getInterfaces().addInterface("127.0.0.1");

        config.addMapConfig(new MapConfig("testMap").setBackupCount(2));
        config.addMapConfig(new MapConfig("otherTestMap"));
        return Hazelcast.newHazelcastInstance(config);
    }

    @Bean
    public IMap<String, String> testMap(HazelcastInstance instance) { // (2)
        return instance.getMap("testMap");
    }

    @Bean
    public IMap<String, String> otherTestMap(HazelcastInstance instance) {
        return instance.getMap("otherTestMap");
    }
}

(1) The HazelcastInstance bean declaration is a standard way of declaring beans in Spring. It uses a plain old Java method. (2) Declaration of bean for testMap IMap, so that you will be able to inject IMap directly into a field.

You can then use Spring’s @Autowired dependency injection annotation to automatically configure objects such as HazelcastInstance and IMap. For example:

/// (...)
@SpringBootApplication
public class SpringApplication {

    @Autowired
    private HazelcastInstance instance;

    @Autowired
    @Qualifier(value = "testMap") // Qualifier is needed because we configured two IMaps, so there are two beans with the same type
    private IMap<String, String> testMap;

As @SpringBootApplication is also a @Configuration class, you could instead move the hazelcastInstance bean declaration to SpringApplication and remove SpringHazelcastConfiguration. However, splitting configuration and usage provides more flexibility. For example, you can use application context creation directly from Java with AnnotationConfigApplicationContext.

Declare beans using XML configuration

While Java-based configuration is now widely used and recommended, you may prefer to use XML-based configuration. You can easily configure Hazelcast using a dedicated hazelcast XML namespace or the common Spring beans XML namespace.

Declare beans using the beans namespace

The following example declares a Hazelcast cluster and IMap using the default Spring beans namespace:

<bean id="instance" class="com.hazelcast.core.Hazelcast" factory-method="newHazelcastInstance">
    <constructor-arg>
        <bean class="com.hazelcast.config.Config">
            <property name="clusterName" value="dev"/>
            <!-- ... -->
        </bean>
    </constructor-arg>
</bean>

<bean id="map" factory-bean="instance" factory-method="getMap">
    <constructor-arg value="map"/>
</bean>

Declare beans using the Hazelcast namespace

Hazelcast has its own namespace hazelcast for bean definitions. You can add the namespace declaration xmlns:hz="http://www.hazelcast.com/schema/spring" to the beans element in the context file so that the hz namespace shortcut can be used as a bean declaration.

Here is an example schema definition:

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:hz="http://www.hazelcast.com/schema/spring"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
                http://www.springframework.org/schema/beans/spring-beans-5.5.xsd
                http://www.hazelcast.com/schema/spring
                http://www.hazelcast.com/schema/spring/hazelcast-spring.xsd">

The following example declares a Hazelcast instance with two cluster members using the hazelcast namespace:

<hz:hazelcast id="instance">
    <hz:config>
        <hz:cluster-name name="dev"/>
        <hz:network port="5701" port-auto-increment="false">
            <hz:join>
                <hz:multicast enabled="false"/>
                <hz:tcp-ip enabled="true">
                    <hz:members>10.10.1.2, 10.10.1.3</hz:members>
                </hz:tcp-ip>
            </hz:join>
        </hz:network>
    </hz:config>
</hz:hazelcast>

Spring property placeholders

You can also pass values using Spring property placeholders. The following example declares a Hazelcast instance and sets a cluster name and Kubernetes service name:

<hz:hazelcast id="instance">
    <hz:config>
        <hz:cluster-name>${my.cluster.name}</hz:cluster-name>
        <!-- ... -->
        <hz:network>
            <hz:join>
                <hz:kubernetes service-name="${my.kubernetes.service.name}" />
            </hz:join>
        </hz:network>
    </hz:config>
</hz:hazelcast>

Supported configuration in the Hazelcast namespace

The hazelcast XML namespace supports the following configuration:

  • Configure a Hazelcast instance

    <hz:hazelcast id="instance">
    <hz:config>
        <hz:cluster-name name="dev"/>
        <hz:network port="5701" port-auto-increment="false">
            <hz:join>
                <hz:multicast enabled="false"
                    multicast-group="224.2.2.3"
                    multicast-port="54327"/>
                <hz:tcp-ip enabled="true">
                    <hz:members>10.10.1.2, 10.10.1.3</hz:members>
                </hz:tcp-ip>
            </hz:join>
        </hz:network>
        <hz:map name="map"
            backup-count="2"
            read-backup-data="true"
            merge-policy="com.hazelcast.spi.merge.PassThroughMergePolicy">
            <hz:eviction eviction-policy="NONE" size="0"/>
        </hz:map>
    </hz:config>
</hz:hazelcast>

  • Configure a Hazelcast client

    <hz:client id="client">
    <hz:cluster-name name="${cluster.name}"/>
    <hz:network connection-timeout="1000"
                redo-operation="true">
        <hz:cluster-routing mode="ALL_MEMBERS"/>
        <hz:member>10.10.1.2:5701</hz:member>
        <hz:member>10.10.1.3:5701</hz:member>
    </hz:network>
</hz:client>

    If you connect to a cluster in a Spring Boot application via the Hazelcast client with security enabled, and you want to see the health of that cluster, you must enable permissions for transactions. For further information, see the following topics:

  • Configure MapStore and NearCache

    For map-store, you should set either the class-name or the implementation attribute.

    <hz:config id="config">
    <hz:map name="map1">
        <hz:map-store enabled="true" class-name="com.foo.DummyStore"
            write-delay-seconds="0" />

        <hz:near-cache time-to-live-seconds="0"
            max-idle-seconds="60" invalidate-on-change="true" >
            <hz:eviction eviction-policy="LRU" size="5000"/>
        </hz:near-cache>
    </hz:map>

    <hz:map name="map2">
        <hz:map-store enabled="true" implementation="dummyMapStore"
            write-delay-seconds="0" />
    </hz:map>
</hz:config>

<bean id="dummyMapStore" class="com.foo.DummyStore" />

Supported data structures

The following table lists all of the Hazelcast data structures you can use in your Spring application.

Data structure Example Java configuration Example XML configuration

map

config.addMapConfig(new MapConfig("aggr") .setInMemoryFormat(InMemoryFormat.OBJECT));

<hz:map id="map" instance-ref="client" name="map" lazy-init="true" />

multiMap

config.addMultiMapConfig(new MultiMapConfig("aggr") .setBinary(false));

<hz:multiMap id="multiMap" instance-ref="instance" name="multiMap" lazy-init="false" />

replicatedmap

config.addReplicatedMapConfig(new ReplicatedMapConfig("aggr") .setInMemoryFormat(InMemoryFormat.OBJECT));

<hz:replicatedMap id="replicatedmap" instance-ref="instance" name="replicatedmap" lazy-init="false" />

queue

config.addQueueConfig(new QueueConfig("aggr") .setMaxSize(1024));

<hz:queue id="queue" instance-ref="client" name="queue" lazy-init="true" depends-on="instance"/>

topic

config.addTopicConfig(new TopicConfig("aggr") .setMultiThreadingEnabled(true));

<hz:topic id="topic" instance-ref="instance" name="topic" depends-on="instance, client"/>

reliableTopic

config.addReliableTopicConfig(new ReliableTopicConfig("aggr") .setTopicOverloadPolicy(TopicOverloadPolicy.BLOCK));

<hz:reliableTopic id="reliableTopic" instance-ref="instance" name="reliableTopic"/>

set

config.addSetConfig(new SetConfig("aggr") .setBackupCount(2));

<hz:set id="set" instance-ref="instance" name="set" />

list

config.addListConfig(new ListConfig("aggr") .setBackupCount(2));

<hz:list id="list" instance-ref="instance" name="list"/>

ringbuffer

config.addRingBufferConfig(new RingbufferConfig("ringbuf") .setBackupCount(1);

<hz:ringbuffer id="ringbuffer" instance-ref="instance" name="ringbuffer"/>

cardinalityEstimator

config.addCardinalityEstimatorConfig(new CardinalityEstimatorConfig("est") .setBackupCount(1);

<hz:cardinalityEstimator id="cardinalityEstimator" instance-ref="instance" name="cardinalityEstimator"/>

flakeIdGenerator

config.addFlakeIdGeneratorConfig(new FlakeIdGeneratorConfig("est") .setBackupCount(1);

<hz:flakeIdGenerator id="flakeIdGenerator" instance-ref="instance" name="flakeIdGenerator"/>

idGenerator

config.addCardinalityEstimatorConfig(new CardinalityEstimatorConfig("gen") .setNodeIdOffset(1);

<hz:idGenerator id="idGenerator" instance-ref="instance" name="idGenerator"/>

atomicLong

- (needs manual bean addition)

<hz:atomicLong id="atomicLong" instance-ref="instance" name="atomicLong"/>

atomicReference

- (needs manual bean addition)

<hz:atomicReference id="atomicReference" instance-ref="instance" name="atomicReference"/>

semaphore Enterprise Edition

config.getCPSubsystemConfig().addSemaphoreConfig(new SemaphoreConfig("s1").setInitialPermits(5));

<hz:semaphore id="semaphore" instance-ref="instance" name="semaphore"/>

countDownLatch

- (needs manual bean addition)

<hz:countDownLatch id="countDownLatch" instance-ref="instance" name="countDownLatch"/>

lock Enterprise Edition

config.getCPSubsystemConfig().addLockConfig(new FencedLockConfig("lock1").setLockAcquireLimit(5));

<hz:lock id="lock" instance-ref="instance" name="lock"/>

cpmap Enterprise Edition

config.getCPSubsystemConfig().addCPMapConfig(new CPMapConfig("cpMap1").setMaxSizeMb(150));

<hz:cpmap instance-ref="instance" name="cpmap" id="cpMap" />

dataConnection

+ [source,java,opts=novalidate] ----- config.addDataConnectionConfig(new DataConnectionConfig() .setName("my-jdbc-data-connection") .setType("Jdbc") .setProperties(getProperties())); ----- +

<hz:external-data-store name="externalStore"> <hz:class-name>com.hazelcast.datastore.JdbcDataStoreFactory</hz:class-name> <hz:properties> <hz:property name="jdbcUrl">jdbc:mysql://dummy:3306</hz:property> </hz:properties> </hz:external-data-store>

executorService

config.addExecutorConfig(new ExecutorConfig("executor1").setPoolSize(100));

<hz:executorService id="executorService" instance-ref="client" name="executorService"/>

durableExecutorService

config.addDurableExecutorConfig(new DurableExecutorConfig("executor1").setPoolSize(100));

<hz:durableExecutorService id="durableExec" instance-ref="instance" name="durableExec"/>

scheduledExecutorService

config.addScheduledExecutorConfig(new ScheduledExecutorConfig("executor1").setPoolSize(100));

<hz:scheduledExecutorService id="scheduledExec" instance-ref="instance" name="scheduledExec"/>

Supported Spring bean attributes

Hazelcast supports the lazy-init, scope and depends-on bean attributes.

<hz:hazelcast id="instance" lazy-init="true" scope="singleton">
    ...
</hz:hazelcast>
<hz:client id="client" scope="prototype" depends-on="instance">
    ...
</hz:client>

Next steps

Once you’ve set up Hazelcast in your Spring application, you can refer to the following sections to configure Hazelcast for common use cases:

For more configuration examples, review our Spring sample application.

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