T
- Element typepublic abstract class EnumeratorCursor<T>
extends org.apache.calcite.avatica.util.PositionedCursor<T>
Cursor
on top of an
Enumerator
that
returns a record for each row. The returned record is cached to avoid
multiple computations of current row.
For instance,
EnumerableCalc
computes result just in current()
method, thus it makes sense to
cache the result and make it available for all the accessors.org.apache.calcite.avatica.util.PositionedCursor.ArrayGetter, org.apache.calcite.avatica.util.PositionedCursor.FieldGetter, org.apache.calcite.avatica.util.PositionedCursor.ListGetter, org.apache.calcite.avatica.util.PositionedCursor.MapGetter<K>, org.apache.calcite.avatica.util.PositionedCursor.ObjectGetter
org.apache.calcite.avatica.util.AbstractCursor.AbstractGetter, org.apache.calcite.avatica.util.AbstractCursor.ArrayAccessor, org.apache.calcite.avatica.util.AbstractCursor.Getter, org.apache.calcite.avatica.util.AbstractCursor.SlotGetter, org.apache.calcite.avatica.util.AbstractCursor.StructGetter
Modifier and Type | Field and Description |
---|---|
private Enumerator<T> |
enumerator |
Modifier | Constructor and Description |
---|---|
protected |
EnumeratorCursor(Enumerator<T> enumerator)
Creates a
EnumeratorCursor |
Modifier and Type | Method and Description |
---|---|
void |
close() |
protected T |
current() |
boolean |
next() |
private final Enumerator<T> enumerator
protected EnumeratorCursor(Enumerator<T> enumerator)
EnumeratorCursor
enumerator
- input enumeratorprotected T current()
current
in class org.apache.calcite.avatica.util.PositionedCursor<T>
public boolean next()
next
in interface org.apache.calcite.avatica.util.Cursor
next
in class org.apache.calcite.avatica.util.AbstractCursor
public void close()
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