openwfe.org.misc.StackMap Maven / Gradle / Ivy
/*
* Copyright (c) 2001-2006, John Mettraux, OpenWFE.org
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* . Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* . Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* . Neither the name of the "OpenWFE" nor the names of its contributors may be
* used to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
* $Id: StackMap.java 3237 2006-09-07 07:48:34Z jmettraux $
*/
//
// StackMap.java
//
// [email protected]
//
// generated with
// jtmpl 1.1.01 2004/05/19 ([email protected])
//
package openwfe.org.misc;
/**
* A map of stacks, where each key matches a stack of objects
*
* CVS Info :
*
$Author: jmettraux $
*
$Id: StackMap.java 3237 2006-09-07 07:48:34Z jmettraux $
*
* @author [email protected]
*/
public class StackMap
{
/*
private final static org.apache.log4j.Logger log = org.apache.log4j.Logger
.getLogger(StackMap.class.getName());
*/
//
// CONSTANTS & co
//
// FIELDS
private final java.util.Map map = new java.util.HashMap();
//
// CONSTRUCTORS
//
// METHODS
/**
* Pushes a value in the stack mapped to the Object key.
*/
public void push (final Object key, final Object value)
{
if (key == null || value == null)
{
throw new IllegalArgumentException
("Key and/or value may not be null");
}
stack(this.map, key, value);
}
/**
* Unstacks and returns the last object pushed for the given key.
*/
public Object pop (final Object key)
{
final java.util.LinkedList values =
(java.util.LinkedList)this.map.get(key);
if (values == null || values.size() < 1) return null;
return values.removeLast();
}
/**
* Unstacks and returns the first object pushed for the given key.
*/
public Object popFirst (final Object key)
{
final java.util.LinkedList values =
(java.util.LinkedList)this.map.get(key);
if (values == null || values.size() < 1) return null;
return values.removeFirst();
}
//
// STATIC METHODS
/**
* Does the work of storing values in lists mapped to keys.
* This method has been made static as it's used directly by some classes
* that don't want to bother with a (closed) StackMap instance.
*/
public static void stack
(final java.util.Map m, final Object key, Object value)
{
java.util.List values = (java.util.List)m.get(key);
if (values == null)
{
values = new java.util.LinkedList();
m.put(key, values);
}
values.add(value);
}
}