/*
 * Copyright (c) 2009, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * 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,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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 */

package com.sun.tools.classfile;


/**
 * A directed relationship between two {@link Dependency.Location Location}s.
 * Subtypes of {@code Dependency} may provide additional detail about the dependency.
 *
 * @see Dependency.Finder
 * @see Dependency.Filter
 * @see Dependencies
 */
public interface Dependency {
    /**
     * A filter used to select dependencies of interest, and to discard others.
     */
    public interface Filter {
        /**
         * Return true if the dependency is of interest.
         * @param dependency the dependency to be considered
         * @return true if and only if the dependency is of interest.
         */
        boolean accepts(Dependency dependency);
    }

    /**
     * An interface for finding the immediate dependencies of a given class file.
     */
    public interface Finder {
        /**
         * Find the immediate dependencies of a given class file.
         * @param classfile the class file to be examined
         * @return the dependencies located in the given class file.
         */
        public Iterable<? extends Dependency> findDependencies(ClassFile classfile);
    }


    /**
     * A location somewhere within a class. Subtypes of {@code Location}
     * may be used to provide additional detail about the location.
     */
    public interface Location {
        /**
         * Get the name of the class containing the location.
         * This name will be used to locate the class file for transitive
         * dependency analysis.
         * @return the name of the class containing the location.
         */
        String getClassName();
    }


    /**
     * Get the location that has the dependency.
     * @return the location that has the dependency.
     */
    Location getOrigin();

    /**
     * Get the location that is being depended upon.
     * @return the location that is being depended upon.
     */
    Location getTarget();
}

