org.apache.poi.ss.formula
Class BaseFormulaEvaluator

java.lang.Object
  org.apache.poi.ss.formula.BaseFormulaEvaluator

All Implemented Interfaces:

WorkbookEvaluatorProvider, FormulaEvaluator

Direct Known Subclasses:

BaseXSSFFormulaEvaluator, HSSFFormulaEvaluator

public abstract class BaseFormulaEvaluator
extends java.lang.Object
implements FormulaEvaluator, WorkbookEvaluatorProvider

Common functionality across file formats for evaluating formula cells.

_bookEvaluator

protected final WorkbookEvaluator _bookEvaluator

BaseFormulaEvaluator

protected BaseFormulaEvaluator(WorkbookEvaluator bookEvaluator)

setupEnvironment

public static void setupEnvironment(java.lang.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(java.util.Map<java.lang.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

_getWorkbookEvaluator

public WorkbookEvaluator _getWorkbookEvaluator()

Description copied from interface: WorkbookEvaluatorProvider

Provide the underlying WorkbookEvaluator

Specified by:

_getWorkbookEvaluator in interface WorkbookEvaluatorProvider

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 HSSFCell 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 evaluateFormulaCellEnum(Cell)}

Specified by:

evaluateInCell in interface FormulaEvaluator

Parameters:

cell -

Returns:

the cell that was passed in, allowing for chained calls

evaluateFormulaCellValue

protected abstract CellValue evaluateFormulaCellValue(Cell cell)

evaluateFormulaCell

public int evaluateFormulaCell(Cell cell)

Deprecated. 3.15. Will return a CellType enum in the future.

If cell contains formula, it evaluates the formula, and saves the result of the formula. The cell remains as a formula cell. If the cell does not contain formula, this method returns -1 and leaves the cell unchanged. Note that the type of the formula result is returned, so you know what kind of cached formula result is also stored with the formula.

 int 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 evaluateInCell(org.apache.poi.ss.usermodel.Cell)

Specified by:

evaluateFormulaCell in interface FormulaEvaluator

Parameters:

cell - The cell to evaluate

Returns:

-1 for non-formula cells, or the type of the formula result

evaluateFormulaCellEnum

public CellType evaluateFormulaCellEnum(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.evaluateFormulaCellEnum(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:

evaluateFormulaCellEnum 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.

Since:

POI 3.15 beta 3

setCellType

protected static void setCellType(Cell cell,
                                  CellValue cv)

createRichTextString

protected abstract RichTextString createRichTextString(java.lang.String str)

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.

evaluateAllFormulaCells

protected static void evaluateAllFormulaCells(Workbook wb,
                                              FormulaEvaluator evaluator)

setIgnoreMissingWorkbooks

public void setIgnoreMissingWorkbooks(boolean ignore)

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:

• by default ignoreMissingWorkbooks=false and POI throws CollaboratingWorkbooksEnvironment.WorkbookNotFoundException if an external reference cannot be resolved
• if ignoreMissingWorkbooks=true then POI uses cached formula result that already exists in the main workbook

Specified by:

setIgnoreMissingWorkbooks in interface FormulaEvaluator

Parameters:

ignore - whether to ignore missing references to external workbooks

setDebugEvaluationOutputForNextEval

public void setDebugEvaluationOutputForNextEval(boolean value)

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