ilex.util.EnvExpander Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of opendcs Show documentation
A collection of software for aggregatting and processing environmental data such as from NOAA GOES satellites.
The newest version!
/*
*  $Id$
*
*  $Log$
*  Revision 1.1.1.1  2014/05/19 15:28:59  mmaloney
*  OPENDCS 6.0 Initial Checkin
*
*  Revision 1.5  2008/12/17 22:52:41  mjmaloney
*  case insensitive compare fix.
*
*  Revision 1.4  2008/12/15 16:51:43  mjmaloney
*  Fixed substring bug.
*
*  Revision 1.3  2008/11/19 13:43:56  mjmaloney
*  synced with opensrc
*
*  Revision 1.13  2008/08/06 21:53:30  satin
*  Corrected error in Date expansion that caused an array-out-of bound error.
*
*  Revision 1.12  2008/06/09 18:50:02  satin
*  Reorganized to facilitate expansions and added the expansion of the variables
*  ${HOME} and ${USER}.
*
*  Revision 1.11  2008/04/15 11:56:49  satin
*  Added constructor to allow the time zone to be specified rather
*  than having it default to the current one.
*
*  Added variable "WYR" that will expand to the current water year.
*  (WYR begins on October 1. )  This is useful to expand in paths that define
*  archival areas for hydrologic data.
*
*  Revision 1.10  2007/11/07 21:44:56  mmaloney
*  dev
*
*  Revision 1.9  2005/06/09 20:53:34  mjmaloney
*  bug fixes.
*
*  Revision 1.8  2005/04/06 12:21:18  mjmaloney
*  dev
*
*  Revision 1.7  2004/09/20 18:11:50  mjmaloney
*  Allow ~myuser as well as ~ for current user's directory.
*
*  Revision 1.6  2004/08/30 14:50:26  mjmaloney
*  Javadocs
*
*  Revision 1.5  2004/08/10 15:48:03  mjmaloney
*  Log message on exit saying lock file was removed.
*
*  Revision 1.4  2003/06/17 15:25:06  mjmaloney
*  Updated library versions to 3.4
*
*  Revision 1.3  2003/06/06 18:17:58  mjmaloney
*  string2props return empty props if passed string is null.
*
*  Revision 1.2  2003/06/05 19:59:48  mjmaloney
*  Support $DATE(format), where format goes with SimpleDateFormat.
*
*  Revision 1.1  2003/05/16 20:12:38  mjmaloney
*  Added EnvExpander. This is preferrable to ShellExpander because
*  it is platform independent.
*
*/
package ilex.util;

import java.util.Date;
import java.util.Calendar;
import java.util.TimeZone;

import org.opendcs.utils.Property;

import java.util.Properties;
import java.io.IOException;
import java.text.SimpleDateFormat;

/**
This class expands environment variables that were placed into system
properties according to the following rules:


  $VARNAME	Will be replaced by the value of the matching environment
  variable. If there is none, the string remains unchanged.
  $HOME		Will be replaced with the current users home directory.
  ~			Will be replaced with the current users home directory.


Note that OS environment variables are not necessarily available to
Java programs unless you use a -Dname=value on the command line.
*/
public class EnvExpander
{
	/**
	Expands a string using System properties.
	@param str the string
	@return expanded string
	*/
	public static String expand( String str )
	{
		return expand(str, System.getProperties());
	}

	/**
	Expands a string using explicit properties set using current date/time.
	@param str the string
	@param props the properties
	@return expanded string
	*/
	public static String expand( String str, Properties props )
	{
		return expand(str, props, new Date());
	}

	
	/**
	Expands a string using explicit properties set and explicit date/time.
	On Unix systems, also allow ~ and ~myname, which get expanded to the
	current user's directory. Note: This cannot be used to expand other user's
	directories.

	@param str the string
	@param props the properties
	@param date the date
	@return expanded string
	*/
	public static String expand( String str, Properties props, Date date )
	{
		String tzname = props.getProperty("TZ");
		return(expand( str, props, date, tzname ));
		
	}
	public static String expand( String str, Properties props, Date date,
				String tzname )
	{
		TimeZone tz;
		
		if (str == null)
			return null;
		if ( tzname == null ) 
			tz = TimeZone.getDefault();
		else
			tz = TimeZone.getTimeZone(tzname);
		StringBuffer output = new StringBuffer();
		int length = str.length();
		for(int i=0; i= Calendar.OCTOBER )
				year++;
			val = "WY"+Integer.toString(year);
		}
		else if (name.equalsIgnoreCase("USER"))
		{
			val = props.getProperty("user.name");
		}
		else if (name.equalsIgnoreCase("HOME"))
		{
			val = props.getProperty("user.home");
		}
		else
		{
			try
			{
				val = Property.getRealPropertyValue(name, null, props, System.getenv());
				/*
				 * We are looking here for the name object getting returned, not the string value.
				 * If a different string object is returned than we can assume it was processed even if the value
				 * is the same and let the user do what they will with configuration
				 */
				if (val == name)
				{
					final String msg = "property value source was not set. Assuming original behavior and retrieving '%1$s' from provided properties object." +
											  "This will be removed in future releases and you should update values to ${java.%1$s} at your earliest convenience.";
					Logger.instance().warning(String.format(msg,name));
					// revert to original behavior.
					val = props.getProperty(name);
				}
			}
			catch(IOException ex)
			{
				Logger.instance().warning("Could not expand value for property " + name + ": " + ex.getLocalizedMessage());
			}
		}
		return val;
	}

	/**
	test main.
	@param args the args
	*/
	public static void main( String[] args )
	{
		System.out.println("Expanded '" + args[0] + "' to '" 
			+ expand(args[0]) + "'");
	}
}