Package de.gebit.integrity.operations.standard

Class AbstractModularStandardOperationProcessor

java.lang.Object

de.gebit.integrity.operations.standard.AbstractModularStandardOperationProcessor

All Implemented Interfaces:

StandardOperationProcessor

Direct Known Subclasses:

DefaultModularStandardOperationProcessor

public abstract class AbstractModularStandardOperationProcessor
extends Object
implements StandardOperationProcessor

Abstract base implementation for a modular processor processing standard operations. This processor builds a kind of abstract syntax tree for evaluation of operations.

Author:

Rene Schneider - initial API and implementation

Constructor Summary

Constructors

Constructor	Description
AbstractModularStandardOperationProcessor()	Creates an instance.

Method Summary

Modifier and Type	Method	Description
protected void	addOperatorInfo(String anOperator, Class<? extends OperatorNode<?,?>> aNodeClass)	Adds an operator.
protected OperatorNode<?,?>	createNode(Operation anOperation, String anOperator, Object aLeftOperand, Object aRightOperand)	Creates a new node.
Object	executeOperation(StandardOperation anOperation)	Evaluates the given StandardOperation and returns the result object (not converted to any specific type).
protected int	getOperatorPrecedence(String anOperator)	Determines the precedence (ordering) of the given operator.
protected abstract void	initializeOperatorInfo()	Initializes all operators by calls to addOperatorInfo(String, Class).
protected OperatorNode<?,?>	parseOperation(StandardOperation anOperation)	Parses the given operation.

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractModularStandardOperationProcessor

public AbstractModularStandardOperationProcessor()

Creates an instance.

Method Detail

initializeOperatorInfo

protected abstract void initializeOperatorInfo()

Initializes all operators by calls to addOperatorInfo(String, Class).

addOperatorInfo

protected void addOperatorInfo(String anOperator,
                               Class<? extends OperatorNode<?,?>> aNodeClass)

Adds an operator.

Parameters:

anOperator - the operator string

aNodeClass - the node class representing this operator

executeOperation

public Object executeOperation(StandardOperation anOperation)
                        throws UnexecutableException

Description copied from interface: StandardOperationProcessor

Evaluates the given StandardOperation and returns the result object (not converted to any specific type).

Specified by:

executeOperation in interface StandardOperationProcessor

Parameters:

anOperation - the operation to execute

Returns:

the result

Throws:

UnexecutableException - in case the operation cannot be executed (such as because we're running in Eclipse and don't have access to variable values)

parseOperation

protected OperatorNode<?,?> parseOperation(StandardOperation anOperation)
                                          throws SecurityException,
                                                 IllegalArgumentException,
                                                 NoSuchMethodException,
                                                 InstantiationException,
                                                 IllegalAccessException,
                                                 InvocationTargetException

Parses the given operation.

Parameters:

anOperation - the operation to parse

Returns:

the AST representing the operation

Throws:

SecurityException

IllegalArgumentException

NoSuchMethodException

InstantiationException

IllegalAccessException

InvocationTargetException

getOperatorPrecedence

protected int getOperatorPrecedence(String anOperator)

Determines the precedence (ordering) of the given operator.

Parameters:

anOperator - the operator to evaluate

Returns:

the numeric precedence (higher = evaluate first)

createNode

protected OperatorNode<?,?> createNode(Operation anOperation,
                                             String anOperator,
                                             Object aLeftOperand,
                                             Object aRightOperand)
                                      throws SecurityException,
                                             NoSuchMethodException,
                                             IllegalArgumentException,
                                             InstantiationException,
                                             IllegalAccessException,
                                             InvocationTargetException

Creates a new node.

Parameters:

anOperator - the operator

aLeftOperand - the left operand (not evaluated)

aRightOperand - the right operand (not evaluated)

Returns:

the node

Throws:

SecurityException

NoSuchMethodException

IllegalArgumentException

InstantiationException

IllegalAccessException

InvocationTargetException