samples/dci-cargo/dcisample_b/src/main/java/org/apache/zest/sample/dcicargo/sample_b/infrastructure/dci/RoleMixin.java

/*
 * Copyright 2011 Marc Grue.
 *
 * 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.apache.zest.sample.dcicargo.sample_b.infrastructure.dci;

import org.apache.zest.api.injection.scope.Structure;
import org.apache.zest.api.query.QueryBuilderFactory;
import org.apache.zest.api.unitofwork.UnitOfWorkFactory;
import org.apache.zest.api.value.ValueBuilderFactory;

/**
 * RoleMixin
 *
 * Base class for Methodful Roles in Contexts
 *
 * Helps "inject" the Context object into the Role Player.
 *
 * The context field name is now "c" since we don't want the word "context" interfere
 * with domain semantics. We could for instance in one domain have some "material context"
 * where "context" is not a DCI Context but the context of some material. In that case a
 * DCI keyword "context" would confuse the semantics. We could also use "ctx", but why not
 * the shortest option? Less typing, and we know what it is. Furthermore a single letter is
 * easier to spot in the code masses than "ctx" (good to be able to quickly spot all uses
 * of the Context).
 */
public abstract class RoleMixin<T extends Context>
{
    // Context object reference
    public T c;

    // Other common role services/methods could be added here...

    @Structure
    public UnitOfWorkFactory uowf;

    @Structure
    public QueryBuilderFactory qbf;

    @Structure
    public ValueBuilderFactory vbf;

    /**
     * setContext is called with method invocation in {@link Context#setContext(Object, Context)}
     * (therefore "never used" according to IDE)
     */
    public void setContext( T context )
    {
        c = context;
    }
}