dk.rode.thesis.interpreter
Class AbstractExpression<E>

java.lang.Object
  dk.rode.thesis.interpreter.AbstractExpression<E>

Type Parameters:

E - The type of value the evaluation of this expression produces.

All Implemented Interfaces:

Expression<E>, Copyable<Expression<E>>, StrictCopyable<Expression<E>>

Direct Known Subclasses:

AssignmentExpression, BinaryExpression, BreakExpression, FlowExpression, NotExpression, SequenceExpression

public abstract class AbstractExpression<E>
extends Object
implements Expression<E>

An abstract expression represents the basic traits of any expression.

An abstract expression is stateless.

Author:

Gunni Rode / rode.dk

Nested Class Summary

Nested classes/interfaces inherited from interface dk.rode.thesis.interpreter.Expression

Expression.SymbolIdiom

Constructor Summary

protected

AbstractExpression() No-arg sub-class constructor.

Method Summary

boolean	contains(Expression<?> expression) Returns true if this expression is or contains the expression supplied as expression, false if not.
boolean	equals(Object object) Returns true if object is an instance of this expression type having the same name and all operands are equal using equals(Object), respectively, false otherwise.
int	hashCode() Returns the hash code of this expression.
String	toString() Returns the string representation of this expression.

Methods inherited from class java.lang.Object

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

Methods inherited from interface dk.rode.thesis.interpreter.Expression

asSymbol, copy, evaluate, name, operands

Constructor Detail

AbstractExpression

protected AbstractExpression()

No-arg sub-class constructor.

Method Detail

contains

public boolean contains(Expression<?> expression)

Description copied from interface: Expression

Returns true if this expression is or contains the expression supplied as expression, false if not.

The test is performed using identity (==).

Unlike Expression.asSymbol(Context), querying for containment cannot handle cyclic expression references!

Specified by:

contains in interface Expression<E>

Parameters:

expression - The expression to test; cannot be null.

Returns:

True if expression is this expression or contained within this expression, false if not.

See Also:

Expression.asSymbol(Context), Context.touch(Expression)

equals

public boolean equals(Object object)

Returns true if object is an instance of this expression type having the same name and all operands are equal using equals(Object), respectively, false otherwise.

Overrides:

equals in class Object

Parameters:

object - The object to test; can be null.

Returns:

True if equal, false if not.

hashCode

public int hashCode()

Returns the hash code of this expression.

Overrides:

hashCode in class Object

Returns:

The hash code; never null.

toString

public String toString()

Returns the string representation of this expression.

Specified by:

toString in interface Expression<E>

Overrides:

toString in class Object

Returns:

The string representation; never null.