PropertiesUtils.java

/*
 * Distributed as part of mchange-commons-java 0.2.11
 *
 * Copyright (C) 2015 Machinery For Change, Inc.
 *
 * Author: Steve Waldman <swaldman@mchange.com>
 *
 * This library is free software; you can redistribute it and/or modify
 * it under the terms of EITHER:
 *
 *     1) The GNU Lesser General Public License (LGPL), version 2.1, as 
 *        published by the Free Software Foundation
 *
 * OR
 *
 *     2) The Eclipse Public License (EPL), version 1.0
 *
 * You may choose which license to accept if you wish to redistribute
 * or modify this work. You may offer derivatives of this work
 * under the license you have chosen, or you may provide the same
 * choice of license which you have been offered here.
 *
 * This software 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.
 *
 * You should have received copies of both LGPL v2.1 and EPL v1.0
 * along with this software; see the files LICENSE-EPL and LICENSE-LGPL.
 * If not, the text of these licenses are currently available at
 *
 * LGPL v2.1: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html
 *  EPL v1.0: http://www.eclipse.org/org/documents/epl-v10.php 
 * 
 */

package com.mchange.v2.util;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.util.Properties; 

public final class PropertiesUtils
{
    public static int getIntProperty( Properties props, String name, int dflt ) throws NumberFormatException
    {
	String unparsed = props.getProperty( name );
	return ( unparsed != null ? Integer.parseInt( unparsed ) : dflt );
    }

    public static Properties fromString(String propsString, String encoding) throws UnsupportedEncodingException
    {
	try
	    {
		Properties out = new Properties();
		if ( propsString != null )
		    {
			byte[] bytes = propsString.getBytes( encoding );
			out.load( new ByteArrayInputStream( bytes ) );
		    }
		return out;
	    }
	catch (UnsupportedEncodingException e)
	    { throw e; }
	catch (IOException e)
	    { throw new Error("Huh? An IOException while working with byte array streams?!", e); }
    }

    public static Properties fromString(String propsString)
    { 
	try { return fromString( propsString, "ISO-8859-1" ); }
	catch (UnsupportedEncodingException e)
	    { throw new Error("Huh? An ISO-8859-1 is an unsupported encoding?!", e); }
    }

    public static String toString(Properties props, String comment, String encoding) throws UnsupportedEncodingException
    {
	try
	    {
		ByteArrayOutputStream baos = new ByteArrayOutputStream();
		props.store( baos, comment);
		baos.flush(); //superfluous but I feel better...
		return new String( baos.toByteArray(), encoding );
	    }
	catch (UnsupportedEncodingException e)
	    { throw e; }
	catch (IOException e)
	    { throw new Error("Huh? An IOException while working with byte array streams?!", e); }
    }

    public static String toString(Properties props, String comment)
    { 
	try { return toString( props, comment, "ISO-8859-1" ); }
	catch (UnsupportedEncodingException e)
	    { throw new Error("Huh? An ISO-8859-1 is an unsupported encoding?!", e); }
    }

    private PropertiesUtils()
    {}
}