teichmann@6865: /* Copyright (C) 2011, 2012, 2013 by Bundesanstalt für Gewässerkunde
teichmann@6865:  * Software engineering by Intevation GmbH
teichmann@6865:  *
teichmann@6865:  * This file is Free Software under the GNU AGPL (>=v3)
teichmann@6865:  * and comes with ABSOLUTELY NO WARRANTY! Check out the
teichmann@6865:  * documentation coming with Dive4Elements River for details.
teichmann@6865:  */
teichmann@6865: 
teichmann@6865: package org.dive4elements.river.utils;
teichmann@6865: 
teichmann@6865: import java.text.DateFormat;
teichmann@6865: import java.util.Collection;
teichmann@6865: import java.util.Date;
teichmann@6865: import java.util.HashMap;
teichmann@6865: import java.util.Map;
teichmann@6865: 
teichmann@6865: import org.apache.log4j.Logger;
teichmann@6865: 
teichmann@6865: public class UniqueDateFormatter {
teichmann@6865: 
teichmann@6865:     private static Logger log = Logger.getLogger(UniqueDateFormatter.class);
teichmann@6865: 
teichmann@6865:     private DateFormat df;
teichmann@6865:     private DateFormat lf;
teichmann@6865:     private Map<String, int[]> collisions;
teichmann@6865: 
teichmann@6865:     public UniqueDateFormatter(
teichmann@6865:         DateFormat df,
teichmann@6865:         DateFormat lf,
teichmann@6865:         Collection<Date> dates
teichmann@6865:     ) {
teichmann@6865:         this.df = df;
teichmann@6865:         this.lf = lf;
teichmann@6865:         collisions = build(dates);
teichmann@6865:     }
teichmann@6865: 
teichmann@6865:     private Map<String, int []> build(Collection<Date> dates) {
teichmann@6865:         Map<String, int []> collisions = new HashMap<String, int[]>();
teichmann@6865:         for (Date d: dates) {
teichmann@6865:             String s = df.format(d);
teichmann@6865:             int [] count = collisions.get(s);
teichmann@6865:             if (count == null) {
teichmann@6865:                 collisions.put(s, count = new int[1]);
teichmann@6865:             }
teichmann@6865:             if (++count[0] > 1) {
teichmann@6865:                 log.debug("date collsion found: " + d);
teichmann@6865:             }
teichmann@6865:         }
teichmann@6865:         return collisions;
teichmann@6865:     }
teichmann@6865: 
teichmann@6865:     public String format(Date date) {
teichmann@6865:         String s = df.format(date);
teichmann@6865:         int [] count = collisions.get(s);
teichmann@6865:         return count == null || count[0] < 2
teichmann@6865:             ? s
teichmann@6865:             : lf.format(date);
teichmann@6865:     }
teichmann@6865: }