net.cnri.repository.search

Interface QueryVisitor<T>

Type Parameters:

T - the return type for the visitor

All Known Implementing Classes:

AbstractQueryVisitorForSearch, AbstractQueryVisitorForSearch.SearchHandles, AbstractQueryVisitorForSearch.SearchObjects

public interface QueryVisitor<T>

A specification of some behavior on each kind of query. The Visitor pattern is OO's crufty answer to structural pattern matching on algebraic types.

To use a QueryVisitor, call the Query.accept(net.cnri.repository.search.QueryVisitor<T>) method on a Query, with the QueryVisitor as parameter.

To implement a QueryVisitor, implement the visit... methods for each query type. Recursive instances (such as BooleanQuery) are handled by passing the QueryVisitor as this to each subquery's accept method.

Method Summary

Methods

Modifier and Type	Method and Description
T	visitAttributeQuery(AttributeQuery query)
T	visitBooleanQuery(BooleanQuery query)
T	visitElementAttributeQuery(ElementAttributeQuery query)
T	visitMatchAllObjectsQuery(MatchAllObjectsQuery query)
T	visitRawQuery(RawQuery query)

Method Detail

visitRawQuery

T visitRawQuery(RawQuery query)
                throws RepositoryException

Throws:

RepositoryException

visitMatchAllObjectsQuery

T visitMatchAllObjectsQuery(MatchAllObjectsQuery query)
                            throws RepositoryException

Throws:

RepositoryException

visitBooleanQuery

T visitBooleanQuery(BooleanQuery query)
                    throws RepositoryException

Throws:

RepositoryException

visitAttributeQuery

T visitAttributeQuery(AttributeQuery query)
                      throws RepositoryException

Throws:

RepositoryException

visitElementAttributeQuery

T visitElementAttributeQuery(ElementAttributeQuery query)
                             throws RepositoryException

Throws:

RepositoryException