com.querydsl.collections

Interface QueryEngine

All Known Implementing Classes:

DefaultQueryEngine

public interface QueryEngine

QueryEngine defines an interface for the evaluation of ColQuery queries

Author:

tiwe

Method Summary

Modifier and Type	Method and Description
long	count(QueryMetadata metadata, java.util.Map<Expression<?>,java.lang.Iterable<?>> iterables) Evaluate the given query and return the count of matched rows
boolean	exists(QueryMetadata metadata, java.util.Map<Expression<?>,java.lang.Iterable<?>> iterables) Evaluate the given query return whether rows where matched
<T> java.util.List<T>	list(QueryMetadata metadata, java.util.Map<Expression<?>,java.lang.Iterable<?>> iterables, Expression<T> projection) Evaluate the given query and return the projection as a list

Method Detail

count

long count(QueryMetadata metadata,
           java.util.Map<Expression<?>,java.lang.Iterable<?>> iterables)

Evaluate the given query and return the count of matched rows

Parameters:

metadata - query metadata

iterables - source contents

Returns:

matching row count

list

<T> java.util.List<T> list(QueryMetadata metadata,
                           java.util.Map<Expression<?>,java.lang.Iterable<?>> iterables,
                           Expression<T> projection)

Evaluate the given query and return the projection as a list

Parameters:

metadata - query metadata

iterables - source contents

Returns:

matching rows

exists

boolean exists(QueryMetadata metadata,
               java.util.Map<Expression<?>,java.lang.Iterable<?>> iterables)

Evaluate the given query return whether rows where matched

Parameters:

metadata - query metadata

iterables - source contents

Returns:

true, if at least one row was matched