/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.jena.util.iterator;
/**
Combines the actions of <code>Map</code> and <code>Filter</code>, mapping
unacceptable objects to <code>null</code> and acceptable ones to their mapped
value.
*/
public interface MapFilter<R,S>
{
/**
a compiled filter and test - returns null if x is unacceptable, and
the mapped value if x is acceptable; clearly useless if the mapping
might deliver null. Tough.
*/
public S accept( R x );
}