com.yahoo.bullet.query.expressions

Class Expression

java.lang.Object

com.yahoo.bullet.query.expressions.Expression

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

BinaryExpression, CastExpression, FieldExpression, ListExpression, NAryExpression, UnaryExpression, ValueExpression

public abstract class Expression
extends Object
implements Serializable

Expressions are used in Bullet queries to filter on, project, and compute potentially complex values based on Bullet record fields. The supported expressions are: - ValueExpression - FieldExpression - UnaryExpression - BinaryExpression - NAryExpression - ListExpression - CastExpression Look at Evaluator to see how expressions are evaluated.

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected com.yahoo.bullet.typesystem.Type	type

Constructor Summary

Constructors

Constructor and Description
Expression()

Method Summary

Modifier and Type	Method and Description
abstract boolean	equals(Object obj)
abstract Evaluator	getEvaluator() Gets a new instance of an evaluator for this expression.
abstract int	hashCode()
String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

type

protected com.yahoo.bullet.typesystem.Type type

Constructor Detail

Expression

public Expression()

Method Detail

getEvaluator

public abstract Evaluator getEvaluator()

Gets a new instance of an evaluator for this expression.

Returns:

A newly-constructed evaluator for this expression.

equals

public abstract boolean equals(Object obj)

Overrides:

equals in class Object

hashCode

public abstract int hashCode()

Overrides:

hashCode in class Object

toString

public String toString()

Overrides:

toString in class Object