/**
* Copyright (c) Codice Foundation
* <p/>
* This is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser
* General Public License as published by the Free Software Foundation, either version 3 of the
* License, or any later version.
* <p/>
* This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without
* even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details. A copy of the GNU Lesser General Public License
* is distributed along with this program and can be found at
* <http://www.gnu.org/licenses/lgpl.html>.
*/
package ddf.catalog.filter;
import org.opengis.filter.Filter;
import ddf.catalog.source.UnsupportedQueryException;
/**
* {@code FilterAdapter} visits a {@link Filter} and invokes {@link FilterDelegate} methods with
* normalized, typed values. A large part of implementing a {@link org.opengis.filter.FilterVisitor} is handling
* expressions, type casting literals, and supporting custom filter logic like {@code FuzzyFunction}
* s. The {@code FilterAdapter} handles all of this common boilerplate functionality. Furthermore,
* sources using the {@code FilterAdapter} will receive future enhancements and ensure basic
* compatibility with Endpoints that use the {@code FilterBuilder}.
* <p>
* To use the {@code FilterAdapter}, a {@code FilterDelegate} for the source is required. Here is an
* example using a text base filter delegate.
*
* <pre>
* FilterDelegate<String> delegate = new FilterToTextDelegate();
*
* FilterAdapter adapter = new FilterAdapterImpl();
*
* String result = adapter.adapt(filter, delegate);
* </pre>
*
* A reference implementation is provided with the DDF Core in the Filter Proxy bundle.
*
* @author ddf.isgs@lmco.com
*
* @see FilterDelegate
*/
public interface FilterAdapter {
/**
* Visit {@code Filter} nodes and invoke {@code FilterDelegate} methods with normalized input.
*
* @param filter
* OGC Filter to visit
* @param filterDelegate
* delegate to invoke will visiting
* @return result of adapted filter output
* @throws UnsupportedQueryException
*/
public <T> T adapt(Filter filter, FilterDelegate<T> filterDelegate)
throws UnsupportedQueryException;
}