org.apache.flink.table.catalog

Class ContextResolvedFunction

java.lang.Object

org.apache.flink.table.catalog.ContextResolvedFunction

@Internal
public final class ContextResolvedFunction
extends Object

This class contains information about a function and its relationship with a Catalog, if any.

There can be 3 kinds of ContextResolvedFunction:

• A permanent function: a function which is stored in a Catalog or is provided by a Module as a system function. It always has an associated unique FunctionIdentifier.
• A temporary function: a function which is stored in the FunctionCatalog (either as a catalog or system function), has an associated unique FunctionIdentifier and is flagged as temporary.
• An anonymous/inline function: a function which is not stored in a catalog or module and doesn't have an associated unique FunctionIdentifier. During Table API translation, BuiltInFunctionDefinitions are treated as anonymous functions in the API builders that get translated to permanent functions if available in the CoreModule.

This class is meant for internal usages. However, it needs to be kept in sync with the public CallExpression which contains similar context information. The convenience methods fromCallExpression(CallExpression) and toCallExpression(List, DataType) allow a symmetric conversion.

Method Summary

Modifier and Type	Method and Description
static ContextResolvedFunction	anonymous(FunctionDefinition functionDefinition)
String	asSummaryString()
boolean	equals(Object o)
static ContextResolvedFunction	fromCallExpression(CallExpression callExpression)
FunctionDefinition	getDefinition()
Optional<FunctionIdentifier>	getIdentifier()
int	hashCode()
boolean	isAnonymous()
boolean	isPermanent()
boolean	isTemporary()
static ContextResolvedFunction	permanent(FunctionIdentifier functionIdentifier, FunctionDefinition functionDefinition)
static ContextResolvedFunction	temporary(FunctionIdentifier functionIdentifier, FunctionDefinition functionDefinition)
CallExpression	toCallExpression(List<ResolvedExpression> resolvedArgs, DataType outputDataType)
String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Method Detail

permanent

public static ContextResolvedFunction permanent(FunctionIdentifier functionIdentifier,
                                                FunctionDefinition functionDefinition)

temporary

public static ContextResolvedFunction temporary(FunctionIdentifier functionIdentifier,
                                                FunctionDefinition functionDefinition)

anonymous

public static ContextResolvedFunction anonymous(FunctionDefinition functionDefinition)

fromCallExpression

public static ContextResolvedFunction fromCallExpression(CallExpression callExpression)

isAnonymous

public boolean isAnonymous()

isTemporary

public boolean isTemporary()

Returns:

true if the function is temporary. An anonymous function is always temporary.

isPermanent

public boolean isPermanent()

getIdentifier

public Optional<FunctionIdentifier> getIdentifier()

getDefinition

public FunctionDefinition getDefinition()

asSummaryString

public String asSummaryString()

toCallExpression

public CallExpression toCallExpression(List<ResolvedExpression> resolvedArgs,
                                       DataType outputDataType)

toString

public String toString()

Overrides:

toString in class Object

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object