PlainAttributes.java :  » Web-Server » simple » simple » http » Java Open Source

/*
 * PlainAttributes.java December 2003
 *
 * Copyright (C) 2003, Niall Gallagher <niallg@users.sf.net>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation.
 *
 * This library 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.  See the 
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General 
 * Public License along with this library; if not, write to the 
 * Free Software Foundation, Inc., 59 Temple Place, Suite 330, 
 * Boston, MA  02111-1307  USA
 */

package simple.http;

import java.util.Hashtable;
import java.util.Set;

/**
 * This is an <code>Attributes</code> object which is used to convey 
 * attributes for a given connection. This is used to describe any 
 * specific attributes that a connection may have, for example any 
 * security policy for HTTPS. The <code>Attributes</code> provide a
 * subset of the methods provided by the <code>Map</code> object.
 * 
 * @author Niall Gallagher   
 */
class PlainAttributes implements Attributes {

   /**
    * Contains the data extracted from the provided attributes.
    */ 
   protected Hashtable table;

   /**
    * Constructor for the <code>PlainAttributes</code> object. This
    * copies the data from the provided instance so that changes 
    * to the created instance to not affect the provide instance.
    *
    * @param copy this is the <code>Attributes</code> to copy
    */ 
   public PlainAttributes(Attributes copy) {
      this.table = new Hashtable();
      this.init(copy);
   }

   /**
    * This method initializes this instance with the data from the
    * provided <code>Attributes</code> object. A copy is made so
    * that changes to the data in this instance will not affect the
    * provided object. The <code>InetAddress</code> is also copied,
    * 
    * @param copy this is the <code>Attributes</code> to copy
    */ 
   private void init(Attributes copy) {
      Object[] list = copy.keySet().toArray();
      
      for(int i = 0; i < list.length; i++){
         String name = (String) list[i];
         table.put(name, copy.get(name));         
      }
   }
        
   /**
    * The <code>put</code> method is used to insert a mapping to
    * the attributes that pairs the issued name with the issued
    * value. The value can be referenced in future by its name.
    *
    * @param name this is the name of the value being inserted
    * @param value this is the named value that is inserted
    */
   public void put(String name, Object value) {
      table.put(name, value);           
   }

   /**
    * The <code>get</code> method is used to retrieve the value
    * mapped to the specified name. If a value does not exist
    * matching the given name, then this returns null.
    * 
    * @param name this is the name of the value to be retrieved
    *  
    * @return returns the value if it exists or null otherwise
    */
   public Object get(String name) {
      return table.get(name);           
   }

   /**
    * The <code>remove</code> method is used to remove the 
    * named value from the attributes. This method will remove
    * the value or returns silently if the name does not exits.
    *
    * @param name this is the name of the value to be removed
    */
   public void remove(String name) {
      table.remove(name);           
   }

   /**
    * To ascertain what mappings exist, the names of all values
    * previously put into this attributes can be retrieved with 
    * this method. This will return a <code>Set</code> that 
    * contains the names of all the mappings added to this.
    *
    * @return this returns all the keys for existing mappings
    */
   public Set keySet() {
      return table.keySet();           
   }

   /**
    * The <code>contains</code> method is used to determine if
    * a mapping exists for the given name. This returns true if
    * the mapping exists or false otherwise.
    *
    * @param name this is the name of the mapping to determine
    *
    * @return returns true if a mapping exists, false otherwise
    */
   public boolean contains(String name) {
      return table.containsKey(name);
   }
}