Domain.java

/*
 * Copyright 2007 - 2017 the original author or authors.
 *
 * 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 net.sf.jailer.domainmodel;

import java.util.HashSet;
import java.util.Set;
import java.util.TreeSet;

import net.sf.jailer.datamodel.Table;

/**
 * Set of functionally related tables. Part of a {@link DomainModel}.
 *  
 * @author Ralf Wisser
 */
public class Domain implements Comparable<Domain> {

	/**
	 * The domain name.
	 */
	public final String name;
	
	/**
	 * Set of tables in this domain.
	 */
	public final Set<Table> tables;
	
	/**
	 * Set of sub-domains.
	 */
	Set<Domain> subDomains = new TreeSet<Domain>();
	
	/**
	 * Set of super-domains.
	 */
	Set<Domain> superDomains = new TreeSet<Domain>();
	
	/**
	 * Constructor.
	 * 
	 * @param name the domain name
	 * @param tables set of tables in this domain
	 */
	Domain(String name, Set<Table> tables) {
		this.name = name;
		this.tables = tables;
	}
	
	/**
	 * Gets sub-domains.
	 * 
	 * @return set of sub-domains
	 */
	public Set<Domain> getSubDomains() {
		return subDomains;
	}
	
	/**
	 * Gets super-domains.
	 * 
	 * @return set of super-domains
	 */
	public Set<Domain> getSuperDomains() {
		return superDomains;
	}
	
	/**
	 * Checks wether this is a sub domain of a given domain.
	 * 
	 * @param domain the domain
	 * @return <code>true</code> iff this is a sub domain of domain
	 */
	public boolean isSubDomainOf(Domain domain) {
		Set<Domain> superClosure = new HashSet<Domain>(superDomains);
		boolean ready = false;
		while (!ready) {
			Set<Domain> increment = new HashSet<Domain>(); 
			for (Domain superDomain: superClosure) {
				increment.addAll(superDomain.superDomains);
			}
			increment.removeAll(superClosure);
			superClosure.addAll(increment);
			if (increment.isEmpty()) {
				break;
			}
		}
		return superClosure.contains(domain);
	}

	public int compareTo(Domain o) {
		return name.compareTo(o.name);
	}
	
	/**
	 * The hash-code.
	 */
	public int hashCode() {
		return name.hashCode();
	}

	/**
	 * Compares domains.
	 */
	public boolean equals(Object other) {
		if (other instanceof Domain) {
			return name.equals(((Domain) other).name);
		}
		return false;
	}

	/**
	 * Stringifies the domain.
	 */
	public String toString() {
		return "Domain " + name;
	}

}