class ActiveRecord::ConnectionAdapters::StatementPool

def [](key)
  cache[key]
end

def []=(sql, stmt)
  while @statement_limit <= cache.size
    dealloc(cache.shift.last)
  end
  cache[sql] = stmt
end

def cache
  @cache[Process.pid]
end

def clear
  cache.each_value do |stmt|
    dealloc stmt
  end
  cache.clear
end

def dealloc(stmt)
  raise NotImplementedError
end

def delete(key)
  dealloc cache[key]
  cache.delete(key)
end

def each(&block)
  cache.each(&block)
end

def initialize(statement_limit = nil)
  @cache = Hash.new { |h, pid| h[pid] = {} }
  @statement_limit = statement_limit || DEFAULT_STATEMENT_LIMIT
end

def key?(key)
  cache.key?(key)
end

def length
  cache.length
end