function _PropertyCache(oRequestor, sResourcePath, mQueryOptions) {
		_Cache.call(this, oRequestor, sResourcePath, mQueryOptions);

		this.oPromise = null;
	}
******************************************************************************************
	// PropertyCache
	//*********************************************************************************************

	/**
Creates a cache for a single property that performs requests using the given requestor.

@param {sap.ui.model.odata.v4.lib._Requestor} oRequestor
  The requestor
@param {string} sResourcePath
  A resource path relative to the service URL
@param {object} [mQueryOptions]
  A map of key-value pairs representing the query string

@alias sap.ui.model.odata.v4.lib._PropertyCache
@constructor