Tag.java

/**
 *
 * This file is part of TRIO.
 *
 * TRIO is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * TRIO 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with TRIO.  If not, see <http://www.gnu.org/licenses/>.
 */
package eu.diversify.trio.core;

import eu.diversify.trio.util.Require;
import java.util.*;

/**
 * A 'tag' used to classify the components of the system
 */
public class Tag implements SystemPart {

    private final String label;
    private final Set<String> targets;

    public Tag(String label, String... targets) {
        this(label, Arrays.asList(targets));
    }

    public Tag(String label, Collection<String> targets) {
        Require.notNull(label, "Invalid 'null' value given a tag label!");
        this.label = label;

        Require.notNull(targets, "Invalid 'null' values given as tag's target");
        Require.notEmpty(targets, "Invalid tags without any target ([] found)!");
        this.targets = new HashSet<String>(targets);
    }

    public Collection<SystemPart> subParts() {
        final List<SystemPart> subparts = new ArrayList<SystemPart>(0);
        return subparts;
    }

    public void begin(SystemVisitor visitor) {
        visitor.enter(this);
    }

    public void end(SystemVisitor visitor) {
        visitor.exit(this);
    }

    @Override
    public int hashCode() {
        int hash = 7;
        hash = 97 * hash + this.label.hashCode();
        hash = 97 * hash + this.targets.hashCode();
        return hash;
    }

    @Override
    public boolean equals(Object obj) {
        if (obj == null) {
            return false;
        }
        if (getClass() != obj.getClass()) {
            return false;
        }
        final Tag other = (Tag) obj;
        return label.equals(other.label) && targets.equals(other.targets);
    }

    public String getLabel() {
        return label;
    }

    public Set<String> getTargets() {
        return Collections.unmodifiableSet(targets);
    }

    @Override
    public String toString() {
        return String.format("%s on %s", label, targets.toString());
    }

}