package org.onlab.jdvue;

import java.util.Objects;

import static com.google.common.base.Objects.toStringHelper;

/**
 * Abstraction of a dependency segment.
 *
 * @author Thomas Vachuska
 */
public class Dependency {

    private final JavaPackage source;
    private final JavaPackage target;

    /**
     * Creates a dependency from the specified source on the given target.
     *
     * @param source source of the dependency
     * @param target target of the dependency
     */
    public Dependency(JavaPackage source, JavaPackage target) {
        this.source = source;
        this.target = target;
    }

    /**
     * Returns the dependency source.
     *
     * @return source Java package
     */
    public JavaPackage getSource() {
        return source;
    }

    /**
     * Returns the dependency target.
     *
     * @return target Java package
     */
    public JavaPackage getTarget() {
        return target;
    }

    @Override
    public boolean equals(Object obj) {
        if (obj instanceof Dependency) {
            Dependency that = (Dependency) obj;
            return Objects.equals(source, that.source) &&
                    Objects.equals(target, that.target);
        }
        return false;
    }

    @Override
    public int hashCode() {
        return Objects.hash(source, target);
    }

    @Override
    public String toString() {
        return toStringHelper(this)
                .add("source", source).add("target", target).toString();
    }

}