Module com.darkcollective.relix.ast

Package com.darkcollective.relix.ast

Record Class LimitNode

java.lang.Object

java.lang.Record

com.darkcollective.relix.ast.LimitNode

Record Components:

offset - the number of tuples to skip; absent means no offset

count - the maximum number of tuples to return; must not be negative

input - the source relation; must not be null

location - the source location of this node; never null

All Implemented Interfaces:

RelNode

public record LimitNode(Optional<Long> offset, Long count, RelNode input, SourceLocation location)
extends Record
implements RelNode

Represents a limit operation (λ) in relational algebra. Returns up to a specified number of tuples, optionally starting from an offset.

Constructor Summary

Constructors

Constructor	Description
LimitNode(Optional<Long> offset, Long count, RelNode input)	Convenience constructor for tests; uses SourceLocation.UNKNOWN.
LimitNode(Optional<Long> offset, Long count, RelNode input, SourceLocation location)	Creates an instance of a LimitNode record class.

Method Summary

Modifier and Type	Method	Description
<R> R	accept(RelNodeVisitor<R> visitor)
Long	count()	Returns the value of the count record component.
final boolean	equals(Object o)	Indicates whether some other object is "equal to" this one.
final int	hashCode()	Returns a hash code value for this object.
RelNode	input()	Returns the value of the input record component.
SourceLocation	location()	Returns the value of the location record component.
Optional<Long>	offset()	Returns the value of the offset record component.
final String	toString()	Returns a string representation of this record class.

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.darkcollective.relix.ast.RelNode

children, mapChildren, materializationMode, prettyPrint

Constructor Details

LimitNode

public LimitNode(Optional<Long> offset,
 Long count,
 RelNode input,
 SourceLocation location)

Creates an instance of a LimitNode record class.

Parameters:

offset - the value for the offset record component

count - the value for the count record component

input - the value for the input record component

location - the value for the location record component

LimitNode

public LimitNode(Optional<Long> offset,
 Long count,
 RelNode input)

Convenience constructor for tests; uses SourceLocation.UNKNOWN.

Method Details

accept

public <R> R accept(RelNodeVisitor<R> visitor)

Specified by:

accept in interface RelNode

toString

public final String toString()

Returns a string representation of this record class. The representation contains the name of the class, followed by the name and value of each of the record components.

Specified by:

toString in class Record

Returns:

a string representation of this object

hashCode

public final int hashCode()

Returns a hash code value for this object. The value is derived from the hash code of each of the record components.

Specified by:

hashCode in class Record

Returns:

a hash code value for this object

equals

public final boolean equals(Object o)

Indicates whether some other object is "equal to" this one. The objects are equal if the other object is of the same class and if all the record components are equal. All components in this record class are compared with Objects::equals(Object,Object).

Specified by:

equals in class Record

Parameters:

o - the object with which to compare

Returns:

true if this object is the same as the o argument; false otherwise.

offset

public Optional<Long> offset()

Returns the value of the offset record component.

Returns:

the value of the offset record component

count

public Long count()

Returns the value of the count record component.

Returns:

the value of the count record component

input

public RelNode input()

Returns the value of the input record component.

Returns:

the value of the input record component

location

public SourceLocation location()

Returns the value of the location record component.

Specified by:

location in interface RelNode

Returns:

the value of the location record component