dk.rode.thesis.interpreter
Class BinaryExpression<T,E>

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

Type Parameters:

T - The type of value the evaluation of the expression operands produces. Normally, but not required to be, identical with E.

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

All Implemented Interfaces:

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

Direct Known Subclasses:

AndExpression, CompareExpression, ConditionalExpression, EqualExpression, OrExpression

public abstract class BinaryExpression<T,E>
extends AbstractExpression<E>
implements NonTerminalExpression<E>

A binary expression represents any expression that involves (at least) two sub-expressions as operands.

The evaluation of a binary expression is not guaranteed to be commutative.

Author:

Gunni Rode / rode.dk

Nested Class Summary

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

Expression.SymbolIdiom

Field Summary

protected Expression<? extends T>	first The first operand.
protected Expression<? extends T>	second The second operand.

Constructor Summary

protected	BinaryExpression(BinaryExpression<? extends T,E> expression) Copy constructor.
protected	BinaryExpression(Expression<? extends T> first, Expression<? extends T> second) Constructor.

Method Summary

protected String	asSymbol(Context context, String separator) Returns x separator y, where x is the symbolic representation of the first expression operand and y of the the second.
protected StringBuilder	asSymbol(Context context, String separator, StringBuilder sb) Returns x separator y, where x is the symbolic representation of the first expression operand and y of the the second.
List<Expression<?>>	operands() Returns the expression operands used by this expression, in order.
String	toString() Returns the string representation of this expression.

Methods inherited from class dk.rode.thesis.interpreter.AbstractExpression

contains, equals, hashCode

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, contains, copy, evaluate, name

Field Detail

first

protected final Expression<? extends T> first

The first operand.

Never null.

second

protected final Expression<? extends T> second

The second operand.

Never null.

Constructor Detail

BinaryExpression

protected BinaryExpression(BinaryExpression<? extends T,E> expression)

Copy constructor.

Parameters:

expression - The expression to copy; cannot be null.

Throws:

NullPointerException - If expression is null.

BinaryExpression

protected BinaryExpression(Expression<? extends T> first,
                           Expression<? extends T> second)

Constructor.

Parameters:

first - The first expression operand; cannot be null.

second - The second expression operand; cannot be null.

Throws:

NullPointerException - If either expression is null.

Method Detail

asSymbol

protected String asSymbol(Context context,
                          String separator)
                   throws ExpressionException

Returns x separator y, where x is the symbolic representation of the first expression operand and y of the the second.

Parameters:

context - The context to use; cannot be null.

separator - The operand separator; cannot be null.

Returns:

A formatted symbol string; never null.

Throws:

NullPointerException - If either argument is null.

ExpressionException - If the symbol cannot be generated.

asSymbol

protected StringBuilder asSymbol(Context context,
                                 String separator,
                                 StringBuilder sb)
                          throws ExpressionException

Returns x separator y, where x is the symbolic representation of the first expression operand and y of the the second.

Parameters:

context - The context to use; cannot be null.

separator - The operand separator; cannot be null.

sb - The string builder to use and return; cannot be null.

Returns:

sb; never null.

Throws:

NullPointerException - If either argument is null.

ExpressionException - If the symbol cannot be generated.

operands

public List<Expression<?>> operands()

Description copied from interface: Expression

Returns the expression operands used by this expression, in order.

Modifying the returned list will not affect this expression.

Specified by:

operands in interface Expression<E>

Returns:

The operands; never null, but can be empty.

toString

public String toString()

Description copied from class: AbstractExpression

Returns the string representation of this expression.

Specified by:

toString in interface Expression<E>

Overrides:

toString in class AbstractExpression<E>

Returns:

The string representation; never null.