Spring Best Practices

Spring tries to create a new Map/Collection instance and fill the new instance by iterating and converting values of the original Map/Collection (IMap, IQueue, etc.) to required types when generic type parameters of the original Map/Collection and the target property/attribute do not match.

Since Hazelcast Maps/Collections are designed to hold very large data which a single machine cannot carry, iterating through whole values can cause out of memory errors.

To avoid this issue, the target property/attribute can be declared as un-typed Map/Collection as shown below.

java

public class SomeBean {
    @Autowired
    IMap map; // instead of IMap<K, V> map

    @Autowired
    IQueue queue; // instead of IQueue<E> queue
    ...
}

Or, parameters of injection methods (constructor, setter) can be un-typed as shown below.

java

public class SomeBean {

    IMap<K, V> map;
    IQueue<E> queue;

    // Instead of IMap<K, V> map
    public SomeBean(IMap map) {
        this.map = map;
    }

    ...

    // Instead of IQueue<E> queue
    public void setQueue(IQueue queue) {
        this.queue = queue;
    }
    ...
}

note

See Spring issue-3407 for more information.