# Visibility.java

    /*
     * Copyright (c) 2007, Rickard Öberg. All Rights Reserved.
     *
     * 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.qi4j.api.common;

    /**
     * Visibility is a core concept in the Zest structure system. It defines the locale of composites and objects, i.e.
     * how far they can be 'seen' and therefor be used.
     * <p>
     * When a Composite or Object is declared in the assembly phase, and no visibility is set, only other
     * composites/objects within the same module can use that declaration. For a declared composite/object to be usable
     * from other modules a higher visibility must be set, either that the Composite/Object can be used by others within
     * the same Layer, or even to be used by those in the layer above.
     * </p>
     */
    public enum Visibility
    {
        /**
         * Artifact is visible only in the declaring module (default)
         */
        module,
        /**
         * Artifact is visible to all modules in the same layer
         */
        layer,
        /**
         * Artifact is visible to other modules in the same layer and any modules in extending layers
         */
        application
    }