org.apache.calcite.schema

Interface Wrapper

All Known Subinterfaces:

Context, Prepare.CatalogReader, Prepare.PreparingTable, RelOptTable, SqlValidatorCatalogReader, SqlValidatorTable

All Known Implementing Classes:

AbstractQueryableTable, AbstractTable, CalciteCatalogReader, DelegatingSqlValidatorCatalogReader, DelegatingSqlValidatorTable, JdbcTable, ListTransientTable, MaterializedViewTable, ModifiableViewTable, Prepare.AbstractPreparingTable, RelOptAbstractTable, RelOptTableImpl, SqlAbstractGroupFunction, SqlAggFunction, SqlAnyValueAggFunction, SqlAvgAggFunction, SqlBasicAggFunction, SqlBitOpAggFunction, SqlCountAggFunction, SqlCovarAggFunction, SqlFirstLastValueAggFunction, SqlHistogramAggFunction, SqlJsonArrayAggAggFunction, SqlJsonObjectAggAggFunction, SqlLeadLagAggFunction, SqlMinMaxAggFunction, SqlNthValueAggFunction, SqlNtileAggFunction, SqlRankFunction, SqlRegrCountAggFunction, SqlSingleValueAggFunction, SqlSumAggFunction, SqlSumEmptyIsZeroAggFunction, SqlUserDefinedAggFunction, StarTable, ViewTable

public interface Wrapper

Mix-in interface that allows you to find sub-objects.

Method Summary

Modifier and Type	Method and Description
default <C> Optional<C>	maybeUnwrap(Class<C> aClass) Finds an instance of an interface implemented by this object, or returns Optional.empty() if this object does not support that interface.
<C> C	unwrap(Class<C> aClass) Finds an instance of an interface implemented by this object, or returns null if this object does not support that interface.
default <C> C	unwrapOrThrow(Class<C> aClass) Finds an instance of an interface implemented by this object, or throws NullPointerException if this object does not support that interface.

Method Detail

unwrap

<C> C unwrap(Class<C> aClass)

Finds an instance of an interface implemented by this object, or returns null if this object does not support that interface.

unwrapOrThrow

@API(since="1.27",
     status=INTERNAL)
default <C> C unwrapOrThrow(Class<C> aClass)

Finds an instance of an interface implemented by this object, or throws NullPointerException if this object does not support that interface.

maybeUnwrap

@API(since="1.27",
     status=INTERNAL)
default <C> Optional<C> maybeUnwrap(Class<C> aClass)

Finds an instance of an interface implemented by this object, or returns Optional.empty() if this object does not support that interface.