Package org.apache.cassandra.cql3.selection

Interface Selectable

All Superinterfaces:

AssignmentTestable

All Known Implementing Classes:

ColumnMetadata, Selectable.BetweenParenthesesOrWithTuple, Selectable.WithArrayLiteral, Selectable.WithCast, Selectable.WithElementSelection, Selectable.WithFieldSelection, Selectable.WithFunction, Selectable.WithList, Selectable.WithMapOrUdt, Selectable.WithSet, Selectable.WithSliceSelection, Selectable.WithTerm, Selectable.WithTypeHint, Selectable.WithVector, Selectable.WritetimeOrTTL

public interface Selectable
extends AssignmentTestable

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static class	Selectable.BetweenParenthesesOrWithTuple	Selectable for Selectable between parentheses or tuples.
static interface	Selectable.Raw
static final class	Selectable.RawIdentifier	In the selection clause, the parser cannot differentiate between Maps and UDTs as a column identifier and field identifier have the same syntax.
static class	Selectable.WithArrayLiteral	Selectable for literal Lists.
static class	Selectable.WithCast
static class	Selectable.WithElementSelection	Represents the selection of an element of a collection (eg.
static class	Selectable.WithFieldSelection	Represents the selection of the field of a UDT (eg.
static class	Selectable.WithFunction
static class	Selectable.WithList
static class	Selectable.WithMapOrUdt	Selectable for literal Maps or UDTs.
static class	Selectable.WithSet	Selectable for literal Sets.
static class	Selectable.WithSliceSelection	Represents the selection of a slice of a collection (eg.
static class	Selectable.WithTerm
static class	Selectable.WithTypeHint	Selectable for type hints (e.g.
static class	Selectable.WithVector
static class	Selectable.WritetimeOrTTL

Nested classes/interfaces inherited from interface org.apache.cassandra.cql3.AssignmentTestable

AssignmentTestable.TestResult

Method Summary

Modifier and Type	Method	Description
default int	addAndGetIndex(ColumnMetadata def, List<ColumnMetadata> l)
default AbstractType<?>	getCompatibleTypeIfKnown(String keyspace)
AbstractType<?>	getExactTypeIfKnown(String keyspace)	The type of the Selectable if it can be infered.
Selector.Factory	newSelectorFactory(TableMetadata table, AbstractType<?> expectedType, List<ColumnMetadata> defs, VariableSpecifications boundNames)
default boolean	processesSelection()	Checks if any processing is performed on the selected columns, false otherwise.
boolean	selectColumns(Predicate<ColumnMetadata> predicate)	Checks if this Selectable select columns matching the specified predicate.
static boolean	selectColumns(List<Selectable> selectables, Predicate<ColumnMetadata> predicate)	Checks if the specified Selectables select columns matching the specified predicate.
default ColumnSpecification	specForElementOrSlice(Selectable selected, ColumnSpecification receiver, CollectionType.Kind kind, String selectionType)
default AssignmentTestable.TestResult	testAssignment(String keyspace, ColumnSpecification receiver)

Method Details

newSelectorFactory

Selector.Factory newSelectorFactory(TableMetadata table,
 AbstractType<?> expectedType,
 List<ColumnMetadata> defs,
 VariableSpecifications boundNames)

getExactTypeIfKnown

AbstractType<?> getExactTypeIfKnown(String keyspace)

The type of the Selectable if it can be infered.

Parameters:

keyspace - the keyspace on which the statement for which this is a Selectable is on.

Returns:

the type of this Selectable if inferrable, or null otherwise (for instance, the type isn't inferable for a bind marker. Even for literals, the exact type is not inferrable since they are valid for many different types and so this will return null too).

selectColumns

boolean selectColumns(Predicate<ColumnMetadata> predicate)

Checks if this Selectable select columns matching the specified predicate.

Returns:

true if this Selectable select columns matching the specified predicate, false otherwise.

selectColumns

static boolean selectColumns(List<Selectable> selectables,
 Predicate<ColumnMetadata> predicate)

Checks if the specified Selectables select columns matching the specified predicate.

Parameters:

selectables - the selectables to check.

Returns:

true if the specified Selectables select columns matching the specified predicate, false otherwise.

processesSelection

default boolean processesSelection()

Checks if any processing is performed on the selected columns, false otherwise.

Returns:

true if any processing is performed on the selected columns, false otherwise.

testAssignment

default AssignmentTestable.TestResult testAssignment(String keyspace,
 ColumnSpecification receiver)

Specified by:

testAssignment in interface AssignmentTestable

Returns:

whether this object can be assigned to the provided receiver. We distinguish between 3 values: - EXACT_MATCH if this object is exactly of the type expected by the receiver - WEAKLY_ASSIGNABLE if this object is not exactly the expected type but is assignable nonetheless - NOT_ASSIGNABLE if it's not assignable Most caller should just call the isAssignable() method on the result, though functions have a use for testing "strong" equality to decide the most precise overload to pick when multiple could match.

getCompatibleTypeIfKnown

default AbstractType<?> getCompatibleTypeIfKnown(String keyspace)

Specified by:

getCompatibleTypeIfKnown in interface AssignmentTestable

Returns:

A data type that can represent this, or null if we can't determine that type. The returned type won't necessarely be the exact type, but one that is compatible with it.

addAndGetIndex

default int addAndGetIndex(ColumnMetadata def,
 List<ColumnMetadata> l)

specForElementOrSlice

default ColumnSpecification specForElementOrSlice(Selectable selected,
 ColumnSpecification receiver,
 CollectionType.Kind kind,
 String selectionType)