org.omegahat.Environment.GUITools
Class OmegaListener

java.lang.Object
  |
  +--org.omegahat.Environment.GUITools.OmegaListener

Direct Known Subclasses:

FunctionListener

public abstract class OmegaListener

extends java.lang.Object

An abstract class that provides slots for storing an evaluable object (expression or Function) and an Evaluator in which it should be evaluated. This is used to implement connect the interpreted language with Java classes by allowing the former to be used as instances of the latter. Methods of the Java class are implemented by evaluating the callback object in the specified org.omegahat.Environment.Interpreter.Envaluator.

Field Summary

protected Evaluable	callback The object which is to be evaluated.
protected Evaluator	evaluator The evaluator in which the evaluation of the callback is to be performed.

Constructor Summary

OmegaListener()
Default constructor for use by derived classes.

OmegaListener(Evaluable callback)
Constructor specifying just the evaluable expression or function.

OmegaListener(Evaluable callback, Evaluator evaluator)
Constructor taking both the callback and evaluator

Method Summary

Evaluable	callback() Accessor to the callback field.
Evaluable	callback(Evaluable cb) Accessor to set the callback field.
java.lang.Object	eval() Evaluate the callback using the specified evaluator, returning the value and trapping any exceptions, displaying them as warnings via the evaluator.
Evaluator	evaluator() Accessor to the evaluator field.
Evaluator	evaluator(Evaluator eval) Accessor to set the evaluator field.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

callback

protected Evaluable callback

The object which is to be evaluated.

evaluator

protected Evaluator evaluator

The evaluator in which the evaluation of the callback is to be performed.

Constructor Detail

OmegaListener

public OmegaListener(Evaluable callback)

Constructor specifying just the evaluable expression or function.

OmegaListener

public OmegaListener(Evaluable callback,
                     Evaluator evaluator)

Constructor taking both the callback and evaluator

OmegaListener

public OmegaListener()

Default constructor for use by derived classes.

Method Detail

evaluator

public Evaluator evaluator()

Accessor to the evaluator field.

evaluator

public Evaluator evaluator(Evaluator eval)

Accessor to set the evaluator field.

callback

public Evaluable callback()

Accessor to the callback field.

callback

public Evaluable callback(Evaluable cb)

Accessor to set the callback field.

eval

public java.lang.Object eval()

Evaluate the callback using the specified evaluator, returning the value and trapping any exceptions, displaying them as warnings via the evaluator.