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

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

Type Parameters:

E - The type of value the evaluation of this expression produces. The value corresponds to the (super-) type of values delivered by the manipulated sequence.

All Implemented Interfaces:

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

@Participant(value="TerminalExpression")
public class CurrentExpression<E>
extends SequenceExpression<E,E>

A current expression will invoke current() on a given sequence when evaluated.

Author:

Gunni Rode / rode.dk

See Also:

NextExpression, SetExpression, ResetExpression, ReverseExpression

Nested Class Summary

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

Expression.SymbolIdiom

Field Summary

Fields inherited from class dk.rode.thesis.interpreter.SequenceExpression

includeHashCode, sequence

Constructor Summary

CurrentExpression(CurrentExpression<E> expression)
Copy constructor.

CurrentExpression(Sequence<? extends E> sequence)
Constructor.

CurrentExpression(Sequence<? extends E> sequence, boolean includeHashCode)
Constructor.

Method Summary

CurrentExpression<E>	copy() Returns a deep copy of this object.
E	evaluate(Context context) Evaluates this expression and returns the result.
String	name() The stand-alone symbol name for this expression.

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

asSymbol, equals, hashCode, operands, toString

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

contains

Methods inherited from class java.lang.Object

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

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

contains

Constructor Detail

CurrentExpression

public CurrentExpression(CurrentExpression<E> expression)

Copy constructor.

The actual sequence manipulated by expression is not copied, but used as is.

Parameters:

expression - The expression to copy; cannot be null.

Throws:

NullPointerException - If expression is null.

CurrentExpression

public CurrentExpression(Sequence<? extends E> sequence)

Constructor.

The identity hash code of sequence is not included in the symbolic representation of this expression.

Parameters:

sequence - The sequence to manipulate by this expression; cannot be null.

Throws:

NullPointerException - If sequence is null.

CurrentExpression

public CurrentExpression(Sequence<? extends E> sequence,
                         boolean includeHashCode)

Constructor.

The identity hash code of sequence is included in the symbolic representation of this expression if includeHashCode is true.

Parameters:

sequence - The sequence to manipulate by this expression; cannot be null.

includeHashCode - True to include the identity hash code of sequence in the symbolic representation, false not to.

Throws:

NullPointerException - If sequence is null.

Method Detail

copy

public CurrentExpression<E> copy()

Description copied from interface: Copyable

Returns a deep copy of this object.

Returns:

The copy; never null.

evaluate

public E evaluate(Context context)
           throws ExpressionException

Description copied from interface: Expression

Evaluates this expression and returns the result.

There is no guarantee that the evaluation of this expression will terminate!

Parameters:

context - The context to use; cannot be null.

Returns:

The result of the evaluation; never null.

Throws:

ExpressionException - If the evaluation fails.

See Also:

Sequence.current()

name

public final String name()

Description copied from interface: Expression

The stand-alone symbol name for this expression.

Returns:

current