Package org.apache.poi.ss.formula

Class BaseFormulaEvaluator

    • Constructor Detail

      • BaseFormulaEvaluator

        protected BaseFormulaEvaluator​(WorkbookEvaluator bookEvaluator)

    • Method Detail

      • setupEnvironment

        public static void setupEnvironment​(String[] workbookNames,
                                    BaseFormulaEvaluator[] evaluators)
        Coordinates several formula evaluators together so that formulas that involve external references can be evaluated.
        Parameters:
        workbookNames - the simple file names used to identify the workbooks in formulas with external links (for example "MyData.xls" as used in a formula "[MyData.xls]Sheet1!A1")
        evaluators - all evaluators for the full set of workbooks required by the formulas.

      • setupReferencedWorkbooks

        public void setupReferencedWorkbooks​(Map<String,​FormulaEvaluator> evaluators)
        Description copied from interface: FormulaEvaluator
        Sets up the Formula Evaluator to be able to reference and resolve links to other workbooks, eg [Test.xls]Sheet1!A1.

        For a workbook referenced as [Test.xls]Sheet1!A1, you should supply a map containing the key Test.xls (no square brackets), and an open FormulaEvaluator onto that Workbook.

        Specified by:
        setupReferencedWorkbooks in interface FormulaEvaluator
        Parameters:
        evaluators - Map of workbook names (no square brackets) to an evaluator on that workbook

      • getEvaluationWorkbook

        protected EvaluationWorkbook getEvaluationWorkbook()
        internal use
        Returns:
        evaluation workbook

      • clearAllCachedResultValues

        public void clearAllCachedResultValues()
        Should be called whenever there are major changes (e.g. moving sheets) to input cells in the evaluated workbook. If performance is not critical, a single call to this method may be used instead of many specific calls to the notify~ methods. Failure to call this method after changing cell values will cause incorrect behaviour of the evaluate~ methods of this class
        Specified by:
        clearAllCachedResultValues in interface FormulaEvaluator

      • evaluate

        public CellValue evaluate​(Cell cell)
        If cell contains a formula, the formula is evaluated and returned, else the CellValue simply copies the appropriate cell value from the cell and also its cell type. This method should be preferred over evaluateInCell() when the call should not modify the contents of the original cell.
        Specified by:
        evaluate in interface FormulaEvaluator
        Parameters:
        cell - may be null signifying that the cell is not present (or blank)
        Returns:
        null if the supplied cell is null or blank

      • evaluateInCell

        public Cell evaluateInCell​(Cell cell)
        If cell contains formula, it evaluates the formula, and puts the formula result back into the cell, in place of the old formula. Else if cell does not contain formula, this method leaves the cell unchanged. Note that the same instance of Cell is returned to allow chained calls like: 
         int evaluatedCellType = evaluator.evaluateInCell(cell).getCellType();
        Be aware that your cell value will be changed to hold the result of the formula. If you simply want the formula value computed for you, use evaluateFormulaCell(Cell)}
        Specified by:
        evaluateInCell in interface FormulaEvaluator
        Parameters:
        cell - The Cell to evaluate and modify.
        Returns:
        the cell that was passed in, allowing for chained calls

      • evaluateFormulaCellValue

        protected abstract CellValue evaluateFormulaCellValue​(Cell cell)

      • evaluateFormulaCell

        public CellType evaluateFormulaCell​(Cell cell)
        If cell contains formula, it evaluates the formula, and saves the result of the formula. The cell remains as a formula cell. Else if cell does not contain formula, this method leaves the cell unchanged. Note that the type of the formula result is returned, so you know what kind of value is also stored with the formula. 
         CellType evaluatedCellType = evaluator.evaluateFormulaCell(cell);
        Be aware that your cell will hold both the formula, and the result. If you want the cell replaced with the result of the formula, use evaluate(org.apache.poi.ss.usermodel.Cell) }
        Specified by:
        evaluateFormulaCell in interface FormulaEvaluator
        Parameters:
        cell - The cell to evaluate
        Returns:
        The type of the formula result (the cell's type remains as CellType.FORMULA however) If cell is not a formula cell, returns CellType._NONE rather than throwing an exception.

      • setCellType

        protected void setCellType​(Cell cell,
                           CellValue cv)
        Set the cell type based on the computed cell type as part of a formula evaluation.
        Parameters:
        cell - The Cell to populate
        cv - The CellValue to read the result type from

      • setCellType

        protected void setCellType​(Cell cell,
                           CellType cellType)
        Override if a different variation is needed, e.g. passing the evaluator to the cell method
        Parameters:
        cell - The Cell to populate
        cellType - The wanted type for this Cell

      • setCellValue

        protected void setCellValue​(Cell cell,
                            CellValue cv)

      • evaluateAllFormulaCells

        public static void evaluateAllFormulaCells​(Workbook wb)
        Loops over all cells in all sheets of the supplied workbook. For cells that contain formulas, their formulas are evaluated, and the results are saved. These cells remain as formula cells. For cells that do not contain formulas, no changes are made. This is a helpful wrapper around looping over all cells, and calling evaluateFormulaCell on each one.

      • setIgnoreMissingWorkbooks

        public void setIgnoreMissingWorkbooks​(boolean ignore)
        Description copied from interface: FormulaEvaluator
        Whether to ignore missing references to external workbooks and use cached formula results in the main workbook instead.

        In some cases external workbooks referenced by formulas in the main workbook are not available. With this method you can control how POI handles such missing references:

        Specified by:
        setIgnoreMissingWorkbooks in interface FormulaEvaluator
        Parameters:
        ignore - whether to ignore missing references to external workbooks

      • setDebugEvaluationOutputForNextEval

        public void setDebugEvaluationOutputForNextEval​(boolean value)
        Description copied from interface: FormulaEvaluator
        Perform detailed output of formula evaluation for next evaluation only? Is for developer use only (also developers using POI for their XLS files). Log-Level WARN is for basic info, INFO for detailed information. These quite high levels are used because you have to explicitly enable this specific logging.
        Specified by:
        setDebugEvaluationOutputForNextEval in interface FormulaEvaluator
        Parameters:
        value - whether to perform detailed output