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/**
 * SCA4J
 * Copyright (c) 2009 - 2099 Service Symphony Ltd
 *
 * Licensed to you under the Apache License, Version 2.0 (the "License"); you may
 * not use this file except in compliance with the License.  A copy of the license
 * is included in this distrubtion or you may obtain a copy at
 *
 *    http://www.opensource.org/licenses/apache2.0.php
 *
 * 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.
 *
 * This project contains code licensed from the Apache Software Foundation under
 * the Apache License, Version 2.0 and original code from project contributors.
 *
 *
 * Original Codehaus Header
 *
 * Copyright (c) 2007 - 2008 fabric3 project contributors
 *
 * Licensed to you under the Apache License, Version 2.0 (the "License"); you may
 * not use this file except in compliance with the License.  A copy of the license
 * is included in this distrubtion or you may obtain a copy at
 *
 *    http://www.opensource.org/licenses/apache2.0.php
 *
 * 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.
 *
 * This project contains code licensed from the Apache Software Foundation under
 * the Apache License, Version 2.0 and original code from project contributors.
 *
 * Original Apache Header
 *
 * Copyright (c) 2005 - 2006 The Apache Software Foundation
 *
 * Apache Tuscany is an effort undergoing incubation at The Apache Software
 * Foundation (ASF), sponsored by the Apache Web Services PMC. Incubation is
 * required of all newly accepted projects until a further review indicates that
 * the infrastructure, communications, and decision making process have stabilized
 * in a manner consistent with other successful ASF projects. While incubation
 * status is not necessarily a reflection of the completeness or stability of the
 * code, it does indicate that the project has yet to be fully endorsed by the ASF.
 *
 * This product includes software developed by
 * The Apache Software Foundation (http://www.apache.org/).
 */
package org.sca4j.spi.binding;

import org.sca4j.spi.model.instance.LogicalReference;
import org.sca4j.spi.model.instance.LogicalService;

/**
 * Implementations are responsible for configuring a binding for a reference targeted to a remote service, that is, one hosted on a different runtime.
 * Binding configuration must be performed in two situations: when the reference targets a service with an explicit binding; and when a service
 * binding is not declared.
 * 
 * In the first case, the binding provider will construct a binding configuration for the reference side of the wire based on the explicitly declared
 * service binding information.
 * 

 * In the second case, when no binding is specified, the reference is said to be wired to a service. In SCA, inter-VM wires use the binding.sca. This
 * binding is abstract. In other words, it represents a remote protocol the particular runtime implementation chooses to effect communication. SCA4J
 * implements binding.sca by delegating to a binding provider, which is responsible for configuring binding information for both sides (reference and
 * serivce) of a wire.
 * 
 * For a given wire, a variety of transport protocols may potentially be used. Which provider is selected depends on the algorithm inforce in a
 * particular domain. For example, a domain may use a weighted algorithm where a particular provider is preferred.
 *
 * @version $Revision$ $Date$
 */
public interface BindingProvider {
    enum MatchType {
        NO_MATCH,
        REQUIRED_INTENTS,
        ALL_INTENTS
    }

    /**
     * Determines if this binding provider can be used as a remote transport for the wire from the source reference to the target service.
     * Implementations must take into account required intents.
     *
     * @param source the source reference
     * @param target the target service
     * @return if the binding provider can wire from the source to target. {@link MatchType#NO_MATCH} indicates the binding provider cannot be used
     *         for the wire; {@link MatchType#REQUIRED_INTENTS} if the provider can be used but not all the mayProvides intents will be supported; and
     *         {@link MatchType#ALL_INTENTS} if all required and mayProvides intents are supported by the provider.
     */
    MatchType canBind(LogicalReference source, LogicalService target);

    /**
     * Configures binding information for the source reference and target service.
     *
     * @param source the source reference
     * @param target the target service
     * @throws BindingSelectionException if some error is encountered that inhibits binding configuration from being generated
     */
    void bind(LogicalReference source, LogicalService target) throws BindingSelectionException;
}