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 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

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package com.sun.xml.internal.bind.v2.model.annotation;

import com.sun.xml.internal.bind.v2.runtime.Location;

/**

 * {@link Location} that is chained.

 *

 * <p>

 * {@link Locatable} forms a tree structure, where each {@link Locatable}

 * points back to the upstream {@link Locatable}.

 * For example, imagine {@link Locatable} X that points to a particular annotation,

 * whose upstream is {@link Locatable} Y, which points to a particular method

 * (on which the annotation is put), whose upstream is {@link Locatable} Z,

 * which points to a particular class (in which the method is defined),

 * whose upstream is {@link Locatable} W,

 * which points to another class (which refers to the class Z), and so on.

 *

 * <p>

 * This chain will be turned into a list when we report the error to users.

 * This allows them to know where the error happened

 * and why that place became relevant.

 *

 * @author Kohsuke Kawaguchi

 */

public interface Locatable {

    /**

     * Gets the upstream {@link Location} information.

     *

     * @return

     *      can be null.

     */

    Locatable getUpstream();

    /**

     * Gets the location object that this object points to.

     *

     * This operation could be inefficient and costly.

     */

    Location getLocation();

}