com.holonplatform.core.query

Interface QueryResults

All Known Subinterfaces:

Query

public interface QueryResults

Provide operations to get results from a Query execution.

Query results are obtained through a projection using QueryProjection, allowing results type specification.

Since:

5.0.0

See Also:

Query

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	QueryResults.QueryExecutionException Exception thrown for Query execution errors.
static class	QueryResults.QueryNonUniqueResultException Exception thrown by when only one query result was expected but more than one found.
static class	QueryResults.QueryResultConversionException Exception thrown for Query results conversion or parsing errors.

Method Summary

Modifier and Type	Method and Description
default long	count() Count all the results of a query.
default <P extends Property> Optional<PropertyBox>	findOne(Iterable<P> properties) Execute query and get an expected unique result as PropertyBox using given properties as projection.
default Optional<PropertyBox>	findOne(Property... properties) Execute query and get an expected unique result as PropertyBox using given properties as projection.
default <R> Optional<R>	findOne(QueryProjection<R> projection) Execute query and get an expected unique result using projection to map result to required type.
default <P extends Property> List<PropertyBox>	list(Iterable<P> properties) Execute query and get a List of query results as PropertyBox using given properties as projection.
default List<PropertyBox>	list(Property... properties) Execute query and get a List of query results as PropertyBox using given properties as projection.
default <R> List<R>	list(QueryProjection<R> projection) Convenience method to obtain query results stream(QueryProjection) as a List
default <P extends Property> Stream<PropertyBox>	stream(Iterable<P> properties) Execute query and get a Stream of query results as PropertyBox using given properties as projection.
default Stream<PropertyBox>	stream(Property... properties) Execute query and get a Stream of query results as PropertyBox using given properties as projection.
<R> Stream<R>	stream(QueryProjection<R> projection) Execute query and get a Stream of query results using given projection to map results to required type.

Method Detail

stream

<R> Stream<R> stream(QueryProjection<R> projection)
              throws QueryResults.QueryExecutionException

Execute query and get a Stream of query results using given projection to map results to required type.

Type Parameters:

R - Results type

Parameters:

projection - Query projection

Returns:

Query results stream

Throws:

QueryResults.QueryExecutionException - Error in query execution

list

default <R> List<R> list(QueryProjection<R> projection)
                  throws QueryResults.QueryExecutionException

Convenience method to obtain query results stream(QueryProjection) as a List

Type Parameters:

R - Results type

Parameters:

projection - Query projection

Returns:

Query results list

Throws:

QueryResults.QueryExecutionException - Error in query execution

findOne

default <R> Optional<R> findOne(QueryProjection<R> projection)
                         throws QueryResults.QueryExecutionException,
                                QueryResults.QueryNonUniqueResultException

Execute query and get an expected unique result using projection to map result to required type.

If more than one result is returned by the query, a QueryResults.QueryNonUniqueResultException is thrown.

Type Parameters:

R - Result type

Parameters:

projection - Query projection

Returns:

Optional unique query result (an empty Optional if no results was returned from query execution)

Throws:

QueryResults.QueryExecutionException - Error in query execution

QueryResults.QueryNonUniqueResultException - Only one result expected but more than one was found

count

default long count()
            throws QueryResults.QueryExecutionException

Count all the results of a query.

Returns:

Total results count

Throws:

QueryResults.QueryExecutionException - Error in query execution

stream

default <P extends Property> Stream<PropertyBox> stream(Iterable<P> properties)
                                                 throws QueryResults.QueryExecutionException

Execute query and get a Stream of query results as PropertyBox using given properties as projection.

Returned PropertyBox instances will contain the values of the properties specified in given properties set.

Type Parameters:

P - Property type

Parameters:

properties - Property set to fetch

Returns:

Query results PropertyBox stream

Throws:

QueryResults.QueryExecutionException - Error in query execution

findOne

default <P extends Property> Optional<PropertyBox> findOne(Iterable<P> properties)
                                                    throws QueryResults.QueryExecutionException,
                                                           QueryResults.QueryNonUniqueResultException

Execute query and get an expected unique result as PropertyBox using given properties as projection.

Returned PropertyBox instance will contain the values of the properties specified in given properties set.

Type Parameters:

P - Property type

Parameters:

properties - Property set to fetch

Returns:

Optional unique query result (an empty Optional if no results was returned from query execution)

Throws:

QueryResults.QueryExecutionException - Error in query execution

QueryResults.QueryNonUniqueResultException - Only one result expected but more than one was found

list

default <P extends Property> List<PropertyBox> list(Iterable<P> properties)
                                             throws QueryResults.QueryExecutionException

Execute query and get a List of query results as PropertyBox using given properties as projection.

Returned PropertyBox instances will contain the values of the properties specified in given properties set.

Type Parameters:

P - Property type

Parameters:

properties - Property set to fetch

Returns:

Query results PropertyBox list

Throws:

QueryResults.QueryExecutionException - Error in query execution

stream

default Stream<PropertyBox> stream(Property... properties)
                            throws QueryResults.QueryExecutionException

Execute query and get a Stream of query results as PropertyBox using given properties as projection.

Returned PropertyBox instances will contain the values of the properties specified in given properties set.

Parameters:

properties - Property set to fetch

Returns:

Query results PropertyBox stream

Throws:

QueryResults.QueryExecutionException - Error in query execution

findOne

default Optional<PropertyBox> findOne(Property... properties)
                               throws QueryResults.QueryExecutionException,
                                      QueryResults.QueryNonUniqueResultException

Execute query and get an expected unique result as PropertyBox using given properties as projection.

Returned PropertyBox instance will contain the values of the properties specified in given properties set.

Parameters:

properties - Property set to fetch

Returns:

Optional unique query result (an empty Optional if no results was returned from query execution)

Throws:

QueryResults.QueryExecutionException - Error in query execution

QueryResults.QueryNonUniqueResultException - Only one result expected but more than one was found

list

default List<PropertyBox> list(Property... properties)
                        throws QueryResults.QueryExecutionException

Execute query and get a List of query results as PropertyBox using given properties as projection.

Returned PropertyBox instances will contain the values of the properties specified in given properties set.

Parameters:

properties - Property set to fetch

Returns:

Query results PropertyBox list

Throws:

QueryResults.QueryExecutionException - Error in query execution