Hazelcast allows querying in collections and arrays. Querying in collections and arrays is compatible with all Hazelcast serialization methods, including the Portable serialization.

Let's have a look at the following data structure expressed in pseudo-code:

class Motorbike {
    Wheel wheels[2];

class Wheel {
   String name;


In order to query a single element of a collection/array, you can execute the following query:

// it matches all motorbikes where the zero wheel's name is 'front-wheel'
Predicate p = Predicates.equal('wheels[0].name', 'front-wheel');
Collection<Motorbike> result = map.values(p);

It is also possible to query a collection/array using the any semantic as shown below:

// it matches all motorbikes where any wheel's name is 'front-wheel'
Predicate p = Predicates.equal('wheels[any].name', 'front');
Collection<Motorbike> result = map.values(p);

The exact same query may be executed using the SQLPredicate as shown below:

Predicate p = new SQLPredicate('wheels[any].name', 'front');
Collection<Motorbike> result = map.values(p);

[] notation applies to both collections and arrays.