/*
 * Copyright 2002-2017 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 org.springframework.jdbc.datasource.init;

import javax.sql.DataSource;

import org.springframework.beans.factory.DisposableBean;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.lang.Nullable;
import org.springframework.util.Assert;

Used to set up a database during initialization and clean up a database during destruction. 
Author:
Dave Syer, Sam Brannen
See Also:
DatabasePopulator
Since:
3.0/**
 * Used to {@linkplain #setDatabasePopulator set up} a database during
 * initialization and {@link #setDatabaseCleaner clean up} a database during
 * destruction.
 *
 * @author Dave Syer
 * @author Sam Brannen
 * @since 3.0
 * @see DatabasePopulator
 */
public class DataSourceInitializer implements InitializingBean, DisposableBean {

	@Nullable
	private DataSource dataSource;

	@Nullable
	private DatabasePopulator databasePopulator;

	@Nullable
	private DatabasePopulator databaseCleaner;

	private boolean enabled = true;


	
The DataSource for the database to populate when this component is initialized and to clean up when this component is shut down. 
This property is mandatory with no default provided.
Params:
dataSource – the DataSource/**
	 * The {@link DataSource} for the database to populate when this component
	 * is initialized and to clean up when this component is shut down.
	 * <p>This property is mandatory with no default provided.
	 * @param dataSource the DataSource
	 */
	public void setDataSource(DataSource dataSource) {
		this.dataSource = dataSource;
	}

	
Set the DatabasePopulator to execute during the bean initialization phase. 
Params:
databasePopulator – the DatabasePopulator to use during initialization
See Also:
setDatabaseCleaner/**
	 * Set the {@link DatabasePopulator} to execute during the bean initialization phase.
	 * @param databasePopulator the {@code DatabasePopulator} to use during initialization
	 * @see #setDatabaseCleaner
	 */
	public void setDatabasePopulator(DatabasePopulator databasePopulator) {
		this.databasePopulator = databasePopulator;
	}

	
Set the DatabasePopulator to execute during the bean destruction phase, cleaning up the database and leaving it in a known state for others. 
Params:
databaseCleaner – the DatabasePopulator to use during destruction
See Also:
setDatabasePopulator/**
	 * Set the {@link DatabasePopulator} to execute during the bean destruction
	 * phase, cleaning up the database and leaving it in a known state for others.
	 * @param databaseCleaner the {@code DatabasePopulator} to use during destruction
	 * @see #setDatabasePopulator
	 */
	public void setDatabaseCleaner(DatabasePopulator databaseCleaner) {
		this.databaseCleaner = databaseCleaner;
	}

	
Flag to explicitly enable or disable the 
database populator and database cleaner. 
Params:
enabled – true if the database populator and database cleaner should be called on startup and shutdown, respectively/**
	 * Flag to explicitly enable or disable the {@linkplain #setDatabasePopulator
	 * database populator} and {@linkplain #setDatabaseCleaner database cleaner}.
	 * @param enabled {@code true} if the database populator and database cleaner
	 * should be called on startup and shutdown, respectively
	 */
	public void setEnabled(boolean enabled) {
		this.enabled = enabled;
	}


	
Use the database populator to set up the database. /**
	 * Use the {@linkplain #setDatabasePopulator database populator} to set up
	 * the database.
	 */
	@Override
	public void afterPropertiesSet() {
		execute(this.databasePopulator);
	}

	
Use the database cleaner to clean up the database. /**
	 * Use the {@linkplain #setDatabaseCleaner database cleaner} to clean up the
	 * database.
	 */
	@Override
	public void destroy() {
		execute(this.databaseCleaner);
	}

	private void execute(@Nullable DatabasePopulator populator) {
		Assert.state(this.dataSource != null, "DataSource must be set");
		if (this.enabled && populator != null) {
			DatabasePopulatorUtils.execute(populator, this.dataSource);
		}
	}

}