source: branches/HeuristicLab.Problems.GrammaticalOptimization/DynamicDataDisplay/Common/ResourcePool.cs @ 13808

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows.Controls;
using System.Diagnostics;
using System.Diagnostics.Contracts;

namespace Microsoft.Research.DynamicDataDisplay.Common
{
  [DebuggerDisplay("Count = {Count}")]
  public sealed class ResourcePool<T>
  {
    private readonly List<T> pool = new List<T>();

    public T Get()
    {
      T item;

      if (pool.Count < 1)
      {
        item = default(T);
      }
      else
      {
        int index = pool.Count - 1;
        item = pool[index];
        pool.RemoveAt(index);
      }

      return item;
    }

    public void Put(T item)
    {
      if (item == null)
        throw new ArgumentNullException("item");

      int index = pool.IndexOf(item);
      if (index != -1)
        throw new InvalidOperationException("Cannot release item that is already contained in pool.");

      pool.Add(item);
    }

    public int Count
    {
      get { return pool.Count; }
    }

    public void Clear()
    {
      pool.Clear();
    }
  }
}