/*
* Copyright 2016 Red Hat, Inc. and/or its affiliates.
*
* Licensed 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.jbpm.services.api.query;
/**
* QueryParamBuilder is responsible for building up one or more filter parameters.
*
* QueryService (that is primary consumer of this builder) will call the
* <code>build</code> method as long as it returns non null value.
* That way it allows to build multiple filters from single builder or build complex
* filters e.g. nested etc with single builder
*
* @param <T> type of filter instances
*/
public interface QueryParamBuilder<T> {
/**
* Builds single condition per invocation and it is invoked as long as it returns non null value.
* @return filter condition to be applied on query or null if done building.
*/
T build();
}