code: function(sOperator) {
  		this.sOperator = sOperator || StringFilterOperator.StartsWith;
  
  		switch (this.sOperator) {
  			case StringFilterOperator.Equals:
  				this.fnOperator = fnEquals;
  				break;
  			case StringFilterOperator.Contains:
  				this.fnOperator = fnContains;
  				break;
  			case StringFilterOperator.StartsWith:
  				this.fnOperator = fnStartsWith;
  				break;
  			case StringFilterOperator.AnyWordStartsWith:
  				this.fnOperator = fnAnyWordStartsWith;
  				break;
  			default:
  				//warning when operator has been given but it doesn't match a value from sap.m.StringFilterOperator enum
  				Log.warning("Unknown string compare operator. Use values from sap.m.StringFilterOperator. Default operator should be used.");
  				this.fnOperator = fnContains;
  				break;
  		}
  	}
docs: String filter helper class.
  @param {string} sOperator sap.m.StringFilterOperator value. Default is sap.m.StringFilterOperator.StartsWith.
  @constructor
  @private