SwitchElementType.java

/*
 * Copyright 2015-2016 Red Hat, Inc. and/or its affiliates
 * and other contributors as indicated by the @author tags.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.hawkular.inventory.api.filters;

import static org.hawkular.inventory.api.Relationships.Direction.incoming;
import static org.hawkular.inventory.api.Relationships.Direction.outgoing;

import org.hawkular.inventory.api.Relationships;

/**
 * Filter for jumping from a vertex to an edge or back. Note that this is different from {@link Related} because
 * it enables one to add additional filters on the relationship after the jump filter.
 */
public final class SwitchElementType extends Filter {
    private final Relationships.Direction direction;
    private final boolean fromEdge;

    public static SwitchElementType incomingRelationships() {
        return new SwitchElementType(incoming, false);
    }

    public static SwitchElementType outgoingRelationships() {
        return new SwitchElementType(outgoing, false);
    }

    public static SwitchElementType sourceEntities() {
        return new SwitchElementType(incoming, true);
    }

    public static SwitchElementType targetEntities() {
        return new SwitchElementType(outgoing, true);
    }

    public SwitchElementType(Relationships.Direction direction, boolean fromEdge) {
        this.direction = direction;
        this.fromEdge = fromEdge;
    }

    public Relationships.Direction getDirection() {
        return direction;
    }

    public boolean isFromEdge() {
        return fromEdge;
    }

    @Override
    public String toString() {
        return "Jump[" + (fromEdge ? "from " : "to ") + direction.name() + " edges]";
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;

        SwitchElementType that = (SwitchElementType) o;

        return this.fromEdge == that.fromEdge && this.direction.equals(that.direction);
    }

    @Override
    public int hashCode() {
        int result = direction != null ? direction.hashCode() : 0;
        result = 31 * result + (fromEdge ? 1 : 0);
        return result;
    }
}