DataValidationEvaluator (POI API Documentation)

java.lang.Object
- org.apache.poi.ss.formula.DataValidationEvaluator

```
public class DataValidationEvaluator
extends java.lang.Object
```
Evaluates Data Validation constraints.
For performance reasons, this class keeps a cache of all previously retrieved DataValidation instances. Be sure to call clearAllCachedValues() if any workbook validation definitions are added, modified, or deleted.
Changing cell values should be fine, as long as the corresponding WorkbookEvaluator.clearAllCachedResultValues() is called as well.

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`static class`	`DataValidationEvaluator.DataValidationContext` This class organizes and encapsulates all the pieces of information related to a single data validation configuration for a single cell.
`static class`	`DataValidationEvaluator.OperatorEnum` Not calling it OperatorType to avoid confusion for now with DataValidationConstraint.OperatorType.
`static class`	`DataValidationEvaluator.ValidationEnum` Not calling it ValidationType to avoid confusion for now with DataValidationConstraint.ValidationType.

Constructor Summary

Constructors
Constructor and Description
`DataValidationEvaluator(Workbook wb, WorkbookEvaluatorProvider provider)` Use the same formula evaluation context used for other operations, so cell value changes are automatically noticed

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`clearAllCachedValues()` Call this whenever validation structures change, so future results stay in sync with the Workbook state.
`DataValidationEvaluator.DataValidationContext`	`getValidationContextForCell(CellReference cell)` Finds and returns the `DataValidationEvaluator.DataValidationContext` for the cell, if there is one.
`DataValidation`	`getValidationForCell(CellReference cell)` Finds and returns the `DataValidation` for the cell, if there is one.
`java.util.List<ValueEval>`	`getValidationValuesForCell(CellReference cell)` If `getValidationForCell(CellReference)` returns an instance, and the `DataValidationConstraint.ValidationType` is `DataValidationConstraint.ValidationType.LIST`, return the valid values, whether they are from a static list or cell range.
`protected static java.util.List<ValueEval>`	`getValidationValuesForConstraint(DataValidationEvaluator.DataValidationContext context)` static so enums can reference it without creating a whole instance
`protected WorkbookEvaluator`	`getWorkbookEvaluator()`
`static boolean`	`isType(Cell cell, CellType type)` Note that this assumes the cell cached value is up to date and in sync with data edits
`boolean`	`isValidCell(CellReference cellRef)` Use the validation returned by `getValidationForCell(CellReference)` if you want the error display details.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - DataValidationEvaluator
```
public DataValidationEvaluator(Workbook wb,
                               WorkbookEvaluatorProvider provider)
```
    Use the same formula evaluation context used for other operations, so cell value changes are automatically noticed
    
    Parameters:
    
    wb - the workbook this operates on
    
    provider - provider for formula evaluation
- Method Detail
  - getWorkbookEvaluator
```
protected WorkbookEvaluator getWorkbookEvaluator()
```
    Returns:
    
    evaluator
  - clearAllCachedValues
```
public void clearAllCachedValues()
```
    Call this whenever validation structures change, so future results stay in sync with the Workbook state.
  - getValidationForCell
```
public DataValidation getValidationForCell(CellReference cell)
```
    Finds and returns the DataValidation for the cell, if there is one. Lookup is based on the first match from DataValidation.getRegions() for the cell's sheet. DataValidation regions must be in the same sheet as the DataValidation. Allowed values expressions may reference other sheets, however.
    
    Parameters:
    
    cell - reference to check - use this in case the cell does not actually exist yet
    
    Returns:
    
    the DataValidation applicable to the given cell, or null if no validation applies
  - getValidationContextForCell
```
public DataValidationEvaluator.DataValidationContext getValidationContextForCell(CellReference cell)
```
    Finds and returns the DataValidationEvaluator.DataValidationContext for the cell, if there is one. Lookup is based on the first match from DataValidation.getRegions() for the cell's sheet. DataValidation regions must be in the same sheet as the DataValidation. Allowed values expressions may reference other sheets, however.
    
    Parameters:
    
    cell - reference to check
    
    Returns:
    
    the DataValidationContext applicable to the given cell, or null if no validation applies
  - getValidationValuesForCell
```
public java.util.List<ValueEval> getValidationValuesForCell(CellReference cell)
```
    If getValidationForCell(CellReference) returns an instance, and the DataValidationConstraint.ValidationType is DataValidationConstraint.ValidationType.LIST, return the valid values, whether they are from a static list or cell range.
    For all other validation types, or no validation at all, this method returns null.
    This method could throw an exception if the validation type is not LIST, but since this method is mostly useful in UI contexts, null seems the easier path.
    
    Parameters:
    
    cell - reference to check - use this in case the cell does not actually exist yet
    
    Returns:
    
    returns an unmodifiable List of ValueEvals if applicable, or null
  - getValidationValuesForConstraint
```
protected static java.util.List<ValueEval> getValidationValuesForConstraint(DataValidationEvaluator.DataValidationContext context)
```
    static so enums can reference it without creating a whole instance
    
    Returns:
    
    returns an unmodifiable List of ValueEvals, which may be empty
  - isValidCell
```
public boolean isValidCell(CellReference cellRef)
```
    Use the validation returned by getValidationForCell(CellReference) if you want the error display details. This is the validation checked by this method, which attempts to replicate Excel's data validation rules.
    Note that to properly apply some validations, care must be taken to offset the base validation formula by the relative position of the current cell, or the wrong value is checked.
    
    Parameters:
    
    cellRef - The reference of the cell to evaluate
    
    Returns:
    
    true if the cell has no validation or the cell value passes the defined validation, false if it fails
  - isType
```
public static boolean isType(Cell cell,
                             CellType type)
```
    Note that this assumes the cell cached value is up to date and in sync with data edits
    
    Parameters:
    
    cell - The Cell to check.
    
    type - The CellType to check for.
    
    Returns:
    
    true if the cell or cached cell formula result type match the given type

Class DataValidationEvaluator

Nested Class Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

DataValidationEvaluator

Method Detail

getWorkbookEvaluator

clearAllCachedValues

getValidationForCell

getValidationContextForCell

getValidationValuesForCell

getValidationValuesForConstraint

isValidCell

isType