cvs commit: jakarta-velocity/src/java/org/apache/velocity/util SimplePool.java

[jvanzyl]

jvanzyl     00/11/12 08:20:43

  Added:       src/java/org/apache/velocity/util SimplePool.java
  Log:
  - add SimplePool for the parser pool.
  
  Revision  Changes    Path
  1.1                  
jakarta-velocity/src/java/org/apache/velocity/util/SimplePool.java
  
  Index: SimplePool.java
  ===================================================================
  package org.apache.velocity.util;
  
  /*
   * $Header: 
/home/cvs/jakarta-velocity/src/java/org/apache/velocity/util/SimplePool.java,v 1.1 
2000/11/12 16:20:43 jvanzyl Exp $
   * $Revision: 1.1 $
   * $Date: 2000/11/12 16:20:43 $
   *
   * ====================================================================
   *
   * The Apache Software License, Version 1.1
   *
   * Copyright (c) 1999 The Apache Software Foundation.  All rights
   * reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   *
   * 2. 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.
   *
   * 3. The end-user documentation included with the redistribution, if
   *    any, must include the following acknowlegement:
   *       "This product includes software developed by the
   *        Apache Software Foundation (http://www.apache.org/)."
   *    Alternately, this acknowlegement may appear in the software itself,
   *    if and wherever such third-party acknowlegements normally appear.
   *
   * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
   *    Foundation" must not be used to endorse or promote products derived
   *    from this software without prior written permission. For written
   *    permission, please contact [EMAIL PROTECTED]
   *
   * 5. Products derived from this software may not be called "Apache"
   *    nor may "Apache" appear in their names without prior written
   *    permission of the Apache Group.
   *
   * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED 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 APACHE SOFTWARE FOUNDATION OR
   * ITS 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.
   * ====================================================================
   *
   * This software consists of voluntary contributions made by many
   * individuals on behalf of the Apache Software Foundation.  For more
   * information on the Apache Software Foundation, please see
   * <http://www.apache.org/>.
   *
   * [Additional notices, if required by prior licensing conditions]
   *
   */
  
  import java.util.zip.*;
  import java.net.*;
  import java.util.*;
  import java.io.*;
  
  /**
   * Simple object pool. Based on ThreadPool and few other classes
   *
   * The pool will ignore overflow and return null if empty.
   *
   * @author Gal Shachor
   * @author Costin
   */
  public final class SimplePool  {
      /*
       * Where the threads are held.
       */
      private Object pool[];
  
      private int max;
      private int minSpare;
      private int maxSpare;
  
      private int current=-1;
  
      Object lock;
      
      public SimplePool(int max) {
        this.max=max;
        pool=new Object[max];
        lock=new Object();
      }
  
      /**
       * Add the object to the pool, silent nothing if the pool is full
       */
      public  void put(Object o) {
        int idx=-1;
        synchronized( lock ) {
            if( current < max )
                idx=++current;
        }
        if( idx > 0 ) 
            pool[idx]=o;
      }
  
      /**
       * Get an object from the pool, null if the pool is empty.
       */
      public  Object get() {
        int idx=-1;
        synchronized( lock ) {
            if( current >= 0 )
                idx=current--;
        }
        if( idx >= 0  ) 
            return pool[idx];
        return null;
      }
  
      /** Return the size of the pool
       */
      public int getMax() {
        return max;
      }
  }