/*

* Copyright (c) 2004-2020 Tada AB and other contributors, as listed below.

*

* All rights reserved. This program and the accompanying materials

* are made available under the terms of the The BSD 3-Clause License

* which accompanies this distribution, and is available at

* http://opensource.org/licenses/BSD-3-Clause

*

* Contributors:

* Tada AB

* Chapman Flack

*/

package org.postgresql.pljava.example;

import java.io.IOException;

import java.io.InputStream;

import java.sql.ResultSet;

import java.sql.SQLException;

import java.util.Enumeration;

import java.util.Properties;

import java.util.logging.Logger;

import org.postgresql.pljava.ObjectPool;

import org.postgresql.pljava.PooledObject;

import org.postgresql.pljava.ResultSetProvider;

import org.postgresql.pljava.SessionManager;

/**

* Illustrates use of the {@code ResultSetProvider} interface to return

* (key,value) rows from the {@code example.properties} file, also making use

* of PL/Java's {@code ObjectPool} facility.

* @author Thomas Hallgren

*/

public class UsingProperties implements ResultSetProvider.Large, PooledObject {

private static Logger s_logger = Logger.getAnonymousLogger();

public static ResultSetProvider getProperties() throws SQLException {

ObjectPool<UsingProperties> pool =

SessionManager.current().getObjectPool(UsingProperties.class);

return (ResultSetProvider) pool.activateInstance();

}

private final Properties m_properties;

private final ObjectPool<UsingProperties> m_pool;

private Enumeration<?> m_propertyIterator;

public UsingProperties(ObjectPool<UsingProperties> pool) throws IOException

{

m_pool = pool;

m_properties = new Properties();

s_logger.info("** UsingProperties()");

InputStream propStream = this.getClass().getResourceAsStream(

"example.properties");

if (propStream == null) {

s_logger.info("example.properties was null");

} else {

m_properties.load(propStream);

propStream.close();

s_logger.info("example.properties has " + m_properties.size()

+ " entries");

}

}

@Override

public void activate() {

s_logger.info("** UsingProperties.activate()");

m_propertyIterator = m_properties.propertyNames();

}

@Override

public boolean assignRowValues(ResultSet receiver, long currentRow)

throws SQLException {

if (m_propertyIterator == null || !m_propertyIterator.hasMoreElements()) {

s_logger.fine("no more rows, returning false");

return false;

}

String propName = (String) m_propertyIterator.nextElement();

receiver.updateString(1, propName);

receiver.updateString(2, m_properties.getProperty(propName));

// s_logger.fine("next row created, returning true");

return true;

}

@Override

public void close() throws SQLException {

m_pool.passivateInstance(this);

}

@Override

public void passivate() {

s_logger.info("** UsingProperties.passivate()");

m_propertyIterator = null;

}

@Override

public void remove() {

s_logger.info("** UsingProperties.remove()");

m_properties.clear();

}

}