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

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


Location that is chained. 
 Locatable forms a tree structure, where each Locatable points back to the upstream Locatable. For example, imagine Locatable X that points to a particular annotation, whose upstream is Locatable Y, which points to a particular method (on which the annotation is put), whose upstream is Locatable Z, which points to a particular class (in which the method is defined), whose upstream is Locatable W, which points to another class (which refers to the class Z), and so on. 

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
/**
 * {@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 Location information. 
Returns:
     can be null.
/**
     * 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.

/**
     * Gets the location object that this object points to.
     *
     * This operation could be inefficient and costly.
     */
    Location getLocation();
}