Utility class for preferences
/*
* Copyright Javelin Software, All rights reserved.
*/
import java.util.*;
import java.util.prefs.*;
/**
* Utility class for prefs
*
* @author Robin Sharp
*/
public class PrefsUtil
{
/**
* Clear all the node
*/
public static void clear( Preferences preferences, String key )
{
try
{
if( preferences.nodeExists( key ) )
{
preferences.node( key ).clear();
}
}
catch( BackingStoreException bse )
{
bse.printStackTrace();
}
}
/**
* Remove the node
*/
public static void remove( Preferences preferences, String key )
{
try
{
if( preferences.nodeExists( key ) )
{
preferences.node( key ).removeNode();
}
}
catch( BackingStoreException bse )
{
bse.printStackTrace();
}
}
/**
* Puts a list into the preferences.
*/
public static void putMap( Preferences preferences, Map map, String key )
{
putMap( preferences.node( key ), map );
}
/**
* Puts a list into the preferences.
*/
public static void putMap( Preferences preferences, Map map )
{
if( preferences == null )
{
throw new IllegalArgumentException( "Preferences not set." );
}
for( Iterator iter = map.entrySet().iterator(); iter.hasNext(); )
{
Map.Entry entry = (Map.Entry)iter.next();
Object value = entry.getValue();
preferences.put( entry.getKey().toString(), value == null ? null : value.toString() );
}
}
/**
* Gets a Map from the preferences.
*/
public static Map getMap( Preferences preferences, String key )
{
return getMap( preferences.node( key ) );
}
/**
* Gets a Map from the preferences.
*/
public static Map getMap( Preferences preferences )
{
if( preferences == null )
{
throw new IllegalArgumentException( "Preferences not set." );
}
Map map = new HashMap();
try
{
String[] keys = preferences.keys();
for( int index = 0; index < keys.length; index++ )
{
map.put( keys[index], preferences.get( keys[index], null ) );
}
}
catch( BackingStoreException bse )
{
bse.printStackTrace();
}
return map;
}
/**
* Puts a list into the preferences starting with "0" then "1"
*/
public static void putList( Preferences preferences, List list, String key )
{
putList( preferences.node( key ), list );
}
/**
* Puts a list into the preferences starting with "0" then "1"
*/
public static void putList( Preferences preferences, List list )
{
if( preferences == null )
{
throw new IllegalArgumentException( "Preferences not set." );
}
//System.out.println( "LIST=" + list );
for( int index = 0; list != null && index < list.size(); index++ )
{
Object value = list.get( index );
preferences.put( ""+index, value == null ? null : value.toString() );
}
}
/**
* Gets a List from the preferences, starting with "0", then "1" etc
*/
public static List getList( Preferences preferences, String key )
{
return getList( preferences.node( key ) );
}
/**
* Gets a List from the preferences, starting with "0", then "1" etc
*/
public static List getList( Preferences preferences )
{
if( preferences == null )
{
throw new IllegalArgumentException( "Preferences not set." );
}
List list = new ArrayList();
for( int index = 0; index < 1000; index++ )
{
String value = preferences.get( ""+index, null );
if( value == null ) break;
//System.out.println( ""+index+ " " + value );
list.add( value );
}
return list;
}
public static void main( String[] args )
{
try
{
Map map = new HashMap();
map.put( "0", "A" );
map.put( "1", "B" );
map.put( "2", "C" );
map.put( "3", "D" );
map.put( "5", "f" );
Preferences prefs = Preferences.userNodeForPackage( String.class );
String RECENT_FILES = "XXX";
List recentFiles = PrefsUtil.getList( prefs, RECENT_FILES );
PrefsUtil.clear( prefs, RECENT_FILES );
PrefsUtil.putList( prefs, recentFiles, RECENT_FILES );
//System.out.println( PrefsUtil.getList( prefs, RECENT_FILES ) );
}
catch( Exception e )
{
e.printStackTrace();
}
}
}
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