org.globus.wsrf.topicexpression
Interface TopicExpressionEvaluator

All Known Implementing Classes:

SimpleTopicExpressionEvaluator

public interface TopicExpressionEvaluator

A TopicExpressionEvaluator is used to implement a topic expression evaluation against a TopicList. An evaluator can be registered with a TopicExpressionEngine, which in turn calls the evaluator when a matching expression is found.

See Also:

TopicList, TopicExpressionEngine

Method Summary

java.util.List	getConcreteTopicPath(TopicExpressionType expression) Converts the expression from dialect specific form to a ordered list of QNames.
java.lang.String[]	getDialects() Gets the URIs for the dialects that this evaluator can handle
java.util.Collection	resolve(TopicExpressionType expression, TopicList topicList) Evaluates the expression over a TopicList and returns the result.
TopicExpressionType	toTopicExpression(java.util.List topicPath) Converts a topic path (list of QNames) to a dialect specific concrete topic expression.

Method Detail

resolve

public java.util.Collection resolve(TopicExpressionType expression,
                                    TopicList topicList)
                             throws UnsupportedTopicExpressionDialectException,
                                    TopicExpressionResolutionException,
                                    InvalidTopicExpressionException,
                                    TopicExpressionException

Evaluates the expression over a TopicList and returns the result.

Parameters:

expression - object passed by client representing the topic expression

topicList - topic list associated with the service/resource

Returns:

the result of the evaluation which depends on the expression.

Throws:

UnsupportedTopicExpressionDialectException - if the topic expression dialect is not supported

TopicExpressionResolutionException - if the expression could not be evaluated

InvalidTopicExpressionException - if the topic expression is invalid

TopicExpressionException - if any other error occurs

getDialects

public java.lang.String[] getDialects()

Gets the URIs for the dialects that this evaluator can handle

Returns:

array of URIs supported by this evaluator

getConcreteTopicPath

public java.util.List getConcreteTopicPath(TopicExpressionType expression)
                                    throws UnsupportedTopicExpressionDialectException,
                                           InvalidTopicExpressionException,
                                           TopicExpressionException

Converts the expression from dialect specific form to a ordered list of QNames. This method throws an exception if the expression does not evaluate to a concrete topic path.

Parameters:

expression - object passed by client representing the topic expression

Returns:

a list of QNames describing the concrete topic path

Throws:

UnsupportedTopicExpressionDialectException - if the topic expression dialect is not supported

InvalidTopicExpressionException - if the topic expression is invalid

TopicExpressionException - if any other error occurs

toTopicExpression

public TopicExpressionType toTopicExpression(java.util.List topicPath)
                                      throws InvalidTopicExpressionException,
                                             TopicExpressionException

Converts a topic path (list of QNames) to a dialect specific concrete topic expression.

Parameters:

topicPath - containing a list of QNames describing a concrete topic path

Returns:

dialect specific version of the topic path

Throws:

InvalidTopicExpressionException - if the conrete topic path is invalid

TopicExpressionException - if any other error occurs