Package com.hazelcast.projection

Interface Projection<I,​O>

  • Type Parameters:
    I - input type
    O - output type
    All Superinterfaces:
    java.io.Serializable
    Functional Interface:
    This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.
    @FunctionalInterface
public interface Projection<I,​O>
extends java.io.Serializable
    Enables transforming object into other objects. Exemplary usage scenario is the project() method of the IMap

    Only 1:1 transformations allowed. Use an Aggregator to perform N:1 or N:M aggregations. 

          IMap<String, Employee> employees = instance.getMap("employees");

      Collection<String> names = employees.project(new Projection<Map.Entry<String,Employee>,String>(){
          @Override
          public String transform(Map.Entry<String, Employee> entry){
              return entry.getValue().getName();
          }
      });
    Since:
    3.8

    • Method Detail

      • transform

        O transform​(I input)
        Transforms the input object into the output object.
        Parameters:
        input - object.
        Returns:
        the output object.