com.bea.p13n.expression
Class ExpressionFactory

java.lang.Object
  com.bea.p13n.expression.ExpressionFactory

public abstract class ExpressionFactory

extends Object

A factory class to create instances of the various implementation classes in the expression package.

Constructor Summary

ExpressionFactory()

Method Summary

static Evaluator	createEvaluator(Map environment) Creates a stateful Evaluator using the supplied environment.
static Evaluator	createEvaluator(Map environment, UnificationList unificationList) Creates an Evaluator object using the supplied environment and a UnificationList.
static Executor	createExecutor(Map environment) Creates an Executor if it is not cached, otherwise returns the cached Executor.
static Expression	createExpression(Map environment, Reader reader) Creates an Expression using the supplied environment, reading and parsing the characters from the supplied reader.
static Expression	createExpression(Map environment, String xmlString) Creates an Expression using the supplied environment and parsing the supplied string.
static Optimizer	createOptimizer(Map environment, ObjectFilter objectFilter) Creates an Optimizer using the supplied environment and an ObjectFilter.
static UnificationList	createUnificationList(Map environment) Creates a UnificationList using the supplied environment.
static Unifier	createUnifier(Map environment, UnificationList unificationList) Creates a Unifier using the supplied environment and the UnificationList.
static Validator	createValidator(Map environment) Creates a stateful Evaluator object using the supplied environment.
static Validator	createValidator(Map environment, Evaluator evaluator) Creates a Validator object using the supplied environment and an Evaluator.

Methods inherited from class java.lang.Object

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

Constructor Detail

ExpressionFactory

public ExpressionFactory()

Method Detail

createEvaluator

public static Evaluator createEvaluator(Map environment)

Creates a stateful Evaluator using the supplied environment.

Parameters:

environment - The environment information to be used during creation of an Evaluator.

Returns:

An Evaluator that can evaluate an expression.

See Also:

Evaluator

createEvaluator

public static Evaluator createEvaluator(Map environment,
                                        UnificationList unificationList)

Creates an Evaluator object using the supplied environment and a UnificationList. If the supplied UnificationList is null then a stateful Evaluator is returned, otherwise a stateless Evaluator is created by associating the supplied UnificationList.

Parameters:

environment - The environment information to be used during creation of an Evaluator.

unificationList - An UnificationList.

Returns:

An Evaluator that can evaluate an expression.

See Also:

Evaluator

createExecutor

public static Executor createExecutor(Map environment)

Creates an Executor if it is not cached, otherwise returns the cached Executor.

Parameters:

environment - The environment information to be used during creation of an Executor.

Returns:

An Executor that can execute an expression.

See Also:

Executor

createExpression

public static Expression createExpression(Map environment,
                                          Reader reader)
                                   throws ExpressionException

Creates an Expression using the supplied environment, reading and parsing the characters from the supplied reader.

Parameters:

environment - The information that is used to create an Expression.

reader - The reader from which the characters will be read and parsed into an expression object.

Returns:

An Expression.

Throws:

ExpressionException - If an error occurs during reading or parsing.

See Also:

Expression

createExpression

public static Expression createExpression(Map environment,
                                          String xmlString)
                                   throws ExpressionException

Creates an Expression using the supplied environment and parsing the supplied string.

Parameters:

environment - The information that is used to create an Expression.

xmlString - The XML string that is read and parsed into an expression object.

Returns:

An Expression.

Throws:

ExpressionException - If an error occurs during parsing.

See Also:

Expression

createOptimizer

public static Optimizer createOptimizer(Map environment,
                                        ObjectFilter objectFilter)

Creates an Optimizer using the supplied environment and an ObjectFilter.

Parameters:

environment - The information that is used to create an Optimizer.

objectFilter - An ObjectFilter that is used during optimization.

Returns:

An Optimizer that can optimize an expression.

See Also:

Optimizer

createUnificationList

public static UnificationList createUnificationList(Map environment)

Creates a UnificationList using the supplied environment.

Parameters:

environment - A Map containing the environment information that is used to create a UnificationList.

Returns:

A UnificationList.

See Also:

UnificationList

createUnifier

public static Unifier createUnifier(Map environment,
                                    UnificationList unificationList)

Creates a Unifier using the supplied environment and the UnificationList.

Parameters:

environment - A Map containing environment information that is used to create a Unifier.

unificationList - A UnificationList that is used to bind variables to their values.

Returns:

A Unifier that can unify an expression.

See Also:

Unifier

createValidator

public static Validator createValidator(Map environment)

Creates a stateful Evaluator object using the supplied environment.

Parameters:

environment - The environment information to be used during creation of the Evaluator.

Returns:

A Validator that can validate an expression.

See Also:

Validator

createValidator

public static Validator createValidator(Map environment,
                                        Evaluator evaluator)

Creates a Validator object using the supplied environment and an Evaluator. If the supplied Evaluator is null then a stateful Validator is returned otherwise a stateless Validator is created by associating the given Evaluator.

Parameters:

environment - The environment information to be used during creation of the Validator.

evaluator - An Evaluator to evaluate an expression during validation.

Returns:

A Validator that can validate an expression.

See Also:

Validator