001// Copyright 2006 The Apache Software Foundation
002//
003// Licensed under the Apache License, Version 2.0 (the "License");
004// you may not use this file except in compliance with the License.
005// You may obtain a copy of the License at
006//
007//     http://www.apache.org/licenses/LICENSE-2.0
008//
009// Unless required by applicable law or agreed to in writing, software
010// distributed under the License is distributed on an "AS IS" BASIS,
011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012// See the License for the specific language governing permissions and
013// limitations under the License.
014
015package org.apache.tapestry5.services;
016
017import org.apache.tapestry5.Binding;
018import org.apache.tapestry5.ComponentResources;
019import org.apache.tapestry5.ioc.Location;
020
021/**
022 * Creates a binding of a particular type.  This is usually invoked from the {@link
023 * org.apache.tapestry5.services.BindingSource} service.
024 */
025public interface BindingFactory
026{
027    /**
028     * Creates a new binding instance.
029     * <p/>
030     * The binding represents a connection between the container and the component (the component is usually the child
031     * of the component, though in a few cases, it is the component itself). In most cases, the expression is evaluated
032     * in terms of the resources of the <em>container</em> and the component is ignored.
033     *
034     * @param description of the binding, such as, "parameter foo"
035     * @param container   the component, as represented by its resources, for which a binding is to be created.
036     * @param component   the component whose parameter is to be bound by the resulting binding (rarely used)
037     * @param expression
038     * @param location    from which the binding was generate, or null if not known
039     * @return the new binding instance
040     */
041    Binding newBinding(String description, ComponentResources container, ComponentResources component,
042                       String expression, Location location);
043}