com.datastax.driver.core

Class FunctionMetadata

java.lang.Object

com.datastax.driver.core.FunctionMetadata

public class FunctionMetadata
extends Object

Describes a CQL function (created with CREATE FUNCTION...).

Method Summary

Modifier and Type	Method and Description
String	asCQLQuery() Returns a CQL query representing this function.
boolean	equals(Object other)
String	exportAsString() Returns a CQL query representing this function in human readable form.
Map<String,DataType>	getArguments() Returns the names and types of this function's arguments.
String	getBody() Returns the body of this function.
KeyspaceMetadata	getKeyspace() Returns the keyspace this function belongs to.
String	getLanguage() Returns the programming language in which this function's body is written.
List<String>	getMonotonicOn() Returns the argument names that the function is monotonic on.
DataType	getReturnType() Returns the return type of this function.
String	getSignature() Returns the CQL signature of this function.
String	getSimpleName() Returns the simple name of this function.
int	hashCode()
boolean	isCalledOnNullInput() Indicates whether this function's body gets called on null input.
boolean	isDeterministic()
boolean	isMonotonic() Indicates whether or not this function is monotonic on all of its arguments.
String	toString()

Methods inherited from class java.lang.Object

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

Method Detail

exportAsString

public String exportAsString()

Returns a CQL query representing this function in human readable form.

This method is equivalent to asCQLQuery() but the output is formatted.

Returns:

the CQL query representing this function.

asCQLQuery

public String asCQLQuery()

Returns a CQL query representing this function.

This method returns a single 'CREATE FUNCTION' query corresponding to this function definition.

Returns:

the 'CREATE FUNCTION' query corresponding to this function.

toString

public String toString()

Overrides:

toString in class Object

getKeyspace

public KeyspaceMetadata getKeyspace()

Returns the keyspace this function belongs to.

Returns:

the keyspace metadata of the keyspace this function belongs to.

getSignature

public String getSignature()

Returns the CQL signature of this function.

This is the name of the function, followed by the names of the argument types between parentheses, for example sum(int,int).

Note that the returned signature is not qualified with the keyspace name.

Returns:

the signature of this function.

getSimpleName

public String getSimpleName()

Returns the simple name of this function.

This is the name of the function, without arguments. Note that functions can be overloaded with different argument lists, therefore the simple name may not be unique. For example, sum(int,int) and sum(int,int,int) both have the simple name sum.

Returns:

the simple name of this function.

See Also:

getSignature()

getArguments

public Map<String,DataType> getArguments()

Returns the names and types of this function's arguments.

Returns:

a map from argument name to argument type.

getBody

public String getBody()

Returns the body of this function.

Returns:

the body.

isCalledOnNullInput

public boolean isCalledOnNullInput()

Indicates whether this function's body gets called on null input.

This is true if the function was created with CALLED ON NULL INPUT, and false if it was created with RETURNS NULL ON NULL INPUT.

Returns:

whether this function's body gets called on null input.

getLanguage

public String getLanguage()

Returns the programming language in which this function's body is written.

Returns:

the language.

getReturnType

public DataType getReturnType()

Returns the return type of this function.

Returns:

the return type.

isDeterministic

public boolean isDeterministic()

Returns:

Whether or not this function is deterministic. This means that given a particular input, the function will always produce the same output.

isMonotonic

public boolean isMonotonic()

Indicates whether or not this function is monotonic on all of its arguments. This means that it is either entirely non-increasing or non-decreasing. Even if the function is not monotonic on all its arguments, it's possible to specify that it is monotonic on one of its arguments, meaning that partial applications of the function over that argument will be monotonic.

Monotonicity is required to use the function in a GROUP BY clause.

Returns:

whether or not this function is monotonic on all of its arguments.

getMonotonicOn

public List<String> getMonotonicOn()

Returns the argument names that the function is monotonic on.

If isMonotonic() returns true, this will return all argument names. Otherwise this will return either one argument or an empty list.

equals

public boolean equals(Object other)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object