xyz.avarel.aje

Class Evaluator

java.lang.Object

xyz.avarel.aje.Evaluator

public class Evaluator
extends java.lang.Object

Used to programmatically evaluate AJE scripts in a read-eval-print-loop manner. Each call to eval(java.lang.String) will affect the state of the evaluator and the following calls. All of the changes to the evaluator are accumulated in the scope field.

Constructor Summary

Constructors

Constructor and Description
Evaluator() Creates a new Evaluator instantiated with default values and functions copied from DefaultScope.
Evaluator(Evaluator parent) Creates a sub-evaluator that can affect the parent evaluator, but any declared variables/functions will not affect the parent evaluator.
Evaluator(Scope scope) Creates a new Evaluator instantiated with default values and functions copied from scope.

Method Summary

Modifier and Type	Method and Description
Obj	eval(AJELexer lexer) Evaluates a stream of tokens from a lexer.
Obj	eval(java.io.File file) Evaluates a file.
Obj	eval(java.io.Reader reader) Evaluates the script read by a reader.
Obj	eval(java.lang.String script) Evaluates a string.
Obj	getAnswer()
Scope	getScope()

Methods inherited from class java.lang.Object

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

Constructor Detail

Evaluator

public Evaluator()

Creates a new Evaluator instantiated with default values and functions copied from DefaultScope.

Evaluator

public Evaluator(Scope scope)

Creates a new Evaluator instantiated with default values and functions copied from scope.

Parameters:

scope - The initial Scope values to copy from.

Evaluator

public Evaluator(Evaluator parent)

Creates a sub-evaluator that can affect the parent evaluator, but any declared variables/functions will not affect the parent evaluator.

Parameters:

parent - The parent Evaluator.

Method Detail

eval

public Obj eval(java.lang.String script)

Evaluates a string. This method changes the state of the scope.

Parameters:

script - The string of AJE expressions.

Returns:

The Obj answer to the script.

Throws:

ComputeException - Error during the execution of the expression.

SyntaxException - Error during the lexing or parsing process of the expression.

eval

public Obj eval(java.io.File file)

Evaluates a file. This method changes the state of the scope.

Parameters:

file - The file containing AJE expressions.

Returns:

The Obj answer to the script.

Throws:

ComputeException - Error during the execution of the expression.

SyntaxException - Error during the lexing or parsing process of the expression.

eval

public Obj eval(java.io.Reader reader)

Evaluates the script read by a reader. This method changes the state of the scope.

Parameters:

reader - The reader instance that reads AJE expressions.

Returns:

The Obj answer to the script.

Throws:

ComputeException - Error during the execution of the expression.

SyntaxException - Error during the lexing or parsing process of the expression.

eval

public Obj eval(AJELexer lexer)

Evaluates a stream of tokens from a lexer. This method changes the state of the scope.

Parameters:

lexer - The lexer object that outputs AJE tokens.

Returns:

The Obj answer to the script.

Throws:

ComputeException - Error during the execution of the expression.

SyntaxException - Error during the lexing or parsing process of the expression.

getAnswer

public Obj getAnswer()

Returns:

The last Obj answer evaluated by this evaluator.

getScope

public Scope getScope()

Returns:

The current Scope of the evaluator.