util/UniqueNameList.java

   1 /*
   2     This class represents a list of (unique) flags, which may exist,
   3     but only once at max. If we add some flag twice, nothing really
   4     happens.
   5
   6     Flaglists can also be used to collect things like search path
   7     arguments, etc.
   8
   9     Operations:
  10
  11         void add(String name)   -> add some flag
  12         void clear(String name) -> clear some flag
  13         String[] getFlagNames() -> lists all flags to an String array
  14
  15 */
  16
  17 package org.de.metux.util;
  18
  19 import java.util.Hashtable;
  20 import java.util.Enumeration;
  21
  22 public class UniqueNameList
  23 {
  24     Hashtable ht = new Hashtable();
  25
  26     public void add(String name)
  27     {
  28         if ((name!=null)&&(name.length()!=0))
  29             ht.put(name,name);
  30     }
  31
  32     public void add(String name[])
  33     {
  34         if (name!=null)
  35             for (int x=0; x<name.length; x++)
  36                 add(name[x]);
  37     }
  38
  39     public void clear(String name)
  40     {
  41         if ((name!=null)&&(name.length()!=0))
  42             ht.remove(name);
  43     }
  44
  45     public String[] getNames()
  46     {
  47         String res[] = new String[ht.size()];
  48         int x=0;
  49         for (Enumeration e=ht.keys(); e.hasMoreElements();)
  50             res[x++]=(String)e.nextElement();
  51         return res;
  52     }
  53
  54     public boolean exists(String name)
  55     {
  56         return (ht.get(name) != null);
  57     }
  58
  59     public String toString()
  60     {
  61         String s = null;
  62         for (Enumeration e=ht.keys(); e.hasMoreElements();)
  63             s = ((s==null)?("{ \""):", \"")+e.nextElement()+"\"";
  64         return s+" }; ";
  65     }
  66 }