spring boot autowired object is getting set to null in ignite persistence cachestore factory class

Question

I am using Apache Ignite 2.3 with cassandra 2.1.9 as my persistence layer. I am using cacheStoreFactory class which saves and gets data from the db. I am auto-wiring some dependencies in this class but it is coming as null.

here is my sample ignite confifuration file:

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="
        http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
       ">
    <description>Main Spring file for ignite configuration.</description>

    <bean id="cacheIgniteBean" class="org.apache.ignite.IgniteSpringBean">
        <property name="configuration">
            <bean id="ignite.cfg" class="org.apache.ignite.configuration.IgniteConfiguration">
                <property name="dataStorageConfiguration">
                    <bean class="org.apache.ignite.configuration.DataStorageConfiguration">
                        <property name="dataRegionConfigurations">
                            <list>
                                <!--
                                    Defining a data region that will consume up to 2 GB of RAM.
                                -->
                                <bean class="org.apache.ignite.configuration.DataRegionConfiguration">
                                    <!-- Custom region name. -->
                                    <property name="name" value="2GB_Region"/>

                                    <!-- 500 MB initial size (RAM). -->
                                    <property name="initialSize" value="#{500L * 1024 * 1024}"/>

                                    <!-- 2 GB maximum size (RAM). -->
                                    <property name="maxSize" value="#{2L * 1024 * 1024 * 1024}"/>

                                    <!-- Enabling RANDOM_LRU eviction for this region.  -->
                                    <property name="pageEvictionMode" value="RANDOM_LRU"/>
                                </bean>
                            </list>
                        </property>
                    </bean>
                </property>
                <property name="cacheConfiguration">
                    <list>
                        <bean class="org.apache.ignite.configuration.CacheConfiguration">

                            <property name="name" value="item"/>
                            <property name="cacheMode" value="PARTITIONED"/>
                            <property name="atomicityMode" value="ATOMIC"/>
                            <property name="backups" value="0"/>
                            <property name="cacheStoreFactory">
                                <bean class="javax.cache.configuration.FactoryBuilder" factory-method="factoryOf">
                                    <constructor-arg value="com.tgt.gom.cacheserver.store.ItemCacheStore"/>
                                </bean>

                            </property>

                            <property name="readThrough" value="${ignite.config.cache.item.readThrough}"/>
                            <property name="writeThrough" value="${ignite.config.cache.item.writeThrough}"/>
                            <property name="writeBehindEnabled" value="${ignite.config.cache.item.writeBehindEnabled}"/>
                            <property name="writeBehindFlushSize"
                                      value="${ignite.config.cache.item.writeBehindFlushSize}"/>
                            <property name="writeBehindFlushFrequency"
                                      value="${ignite.config.cache.item.writeBehindFlushFrequency}"/>
                            <property name="writeBehindFlushThreadCount"
                                      value="${ignite.config.cache.item.writeBehindFlushThreadCount}"/>
                            <property name="writeBehindBatchSize"
                                      value="${ignite.config.cache.item.writeBehindBatchSize}"/>
                        </bean>

                        <bean class="org.apache.ignite.configuration.CacheConfiguration">

                            <property name="name" value="location"/>
                            <property name="cacheMode" value="PARTITIONED"/>
                            <property name="atomicityMode" value="ATOMIC"/>
                            <property name="backups" value="0"/>
                            <property name="cacheStoreFactory">
                                <bean class="javax.cache.configuration.FactoryBuilder" factory-method="factoryOf">
                                    <constructor-arg value="com.tgt.gom.cacheserver.store.LocationCacheStore"/>
                                </bean>
                            </property>
                            <property name="readThrough" value="${ignite.config.cache.item.readThrough}"/>
                            <property name="writeThrough" value="${ignite.config.cache.item.writeThrough}"/>
                            <property name="writeBehindEnabled" value="${ignite.config.cache.item.writeBehindEnabled}"/>
                            <property name="writeBehindFlushSize"
                                      value="${ignite.config.cache.item.writeBehindFlushSize}"/>
                            <property name="writeBehindFlushFrequency"
                                      value="${ignite.config.cache.item.writeBehindFlushFrequency}"/>
                            <property name="writeBehindFlushThreadCount"
                                      value="${ignite.config.cache.item.writeBehindFlushThreadCount}"/>
                            <property name="writeBehindBatchSize"
                                      value="${ignite.config.cache.item.writeBehindBatchSize}"/>
                        </bean>

                    </list>
                </property>

                <!--<property name="includeEventTypes">
                    <util:constant static-field="org.apache.ignite.events.EventType.EVTS_TASK_EXECUTION"/>
                </property>-->
                <property name="failureDetectionTimeout" value="5000"/>
                <property name="discoverySpi">
                    <bean class="org.apache.ignite.spi.discovery.tcp.TcpDiscoverySpi">
                        <property name="ipFinder">
                            <bean class="org.apache.ignite.spi.discovery.tcp.ipfinder.vm.TcpDiscoveryVmIpFinder">
                                <!-- <bean class="org.apache.ignite.spi.discovery.tcp.ipfinder.multicast.TcpDiscoveryMulticastIpFinder"> -->
                                <property name="addresses">
                                    <list>
                                        <value>127.0.0.1:47500..47509</value>
                                    </list>
                                </property>
                            </bean>
                        </property>
                    </bean>
                </property>
            </bean>
        </property>
    </bean>
</beans>

Here is my ItemCacheStore class code:

@Slf4j
@Service
public class ItemCacheStore extends CacheStoreAdapter<String, ItemV1DTO> implements Serializable {
    private static final long serialVersionUID = 1L;


    @Autowired
    private ItemRepository itemRepository;

    @Autowired
    private ItemCacheStoreAsync itemCacheStoreAsync;

    private static final String LOG_OP_INFO = "Item_Cache_Store";


    @Override
    public ItemV1DTO load(String item_id) throws CacheLoaderException {
        ItemV1DTO itemV1DTO = null;
        System.out.println("in item cache store ");

        try {
            ItemEntity itemEntity = itemRepository.findOne(item_id);
            if (itemEntity != null) {
                itemV1DTO = mapToItemDTO(itemEntity);
            }
        } catch (Exception e) {
            throw new CacheLoaderException("failed to load item data from cassandra" + e.getMessage());
        }
        return itemV1DTO;
    }
}

In ItemCacheStore class when the load method is called, the itemRepository field is null. However, when I autowire the same ItemRepository bean in another controller class, it works fine.

One more thing I noticed is that if I put one method with @PostConstruct annotation in the ItemCacheStore class then at that time I can see that dependency of ItemRepository got injected but when load method is called then it is again null.

score 0 · Accepted Answer · answered Dec 13 '17 at 13:51

The issue is the following configuration:

<property name="cacheStoreFactory">
    <bean class="javax.cache.configuration.FactoryBuilder" factory-method="factoryOf">
        <constructor-arg value="com.tgt.gom.cacheserver.store.ItemCacheStore"/>
    </bean>
</property>

You're creating a Spring bean of type FactoryBuilder and you pass the classname ItemCacheStore. What happens behind the screens is that the FactoryBuilder will create a new instance of ItemCacheStore. This new instance won't be managed by Spring, so all fields will be null.

So basically you'll end up with two instances of ItemCacheStore:

One created by the Spring container thanks to the @Service annotation. All autowired fields will work.
Another one create by the FactoryBuilder. It won't be managed by Spring and all autowired fields will be null.

To fix this, there are a few possibilities:

Use a different factory or write your own that will use a Spring managed bean rather than creating a new one. According to the documentation, there is already a CassandraCacheStoreFactory.
Use an AutowireHelper as mentioned in this answer, or use Springs SpringBeanAutowiringSupport to inject beans in a non-Spring managed bean.

Related: Why is my Spring @Autowired field null?

spring boot autowired object is getting set to null in ignite persistence cachestore factory class

1 Answers1