com.aspose.cells

Class AbstractCalculationEngine

java.lang.Object

com.aspose.cells.AbstractCalculationEngine

public abstract class AbstractCalculationEngine
extends java.lang.Object

Represents user's custom calculation engine to extend the default calculation engine of Aspose.Cells.

Remarks

User should not modify any part of the Workbook directly in this implementation(except the calculated result of the custom function, which can be set by CalculationData.CalculatedValue property). Otherwise unexpected result or Exception may be caused. If user needs to change other data than calculated result in the implementation for some custom functions, for example, change cell's formula, style, ...etc., user should gather those data in this implementation and change them out of the scope of formula calculation.

Example

 
         class MyEngine extends AbstractCalculationEngine
         {
             public /*override*/ void calculate(CalculationData data)
             {
                 String funcName = data.getFunctionName().toUpperCase();
                 if ("MYFUNC".equals(funcName))
                 {
                     //do calculation for MYFUNC here
                     int count = data.getParamCount();
                     Object res = null;
                     for (int i = 0; i <count; i++)
                     {
                         Object pv = data.getParamValue(i);
                         if (pv instanceof ReferredArea)
                         {
                             ReferredArea ra = (ReferredArea)pv;
                             pv = ra.getValue(0, 0);
                         }
                         //process the parameter here
                         //res = ...;
                     }
                     data.setCalculatedValue(res);
                 }
             }
         }
         Workbook wb = new Workbook("custom_calc.xlsx");
         CalculationOptions opts = new CalculationOptions();
         opts.setCustomEngine(new MyEngine());
         wb.calculateFormula(opts);
 
 

Constructor Summary

Constructors

Constructor and Description
AbstractCalculationEngine()

Method Summary

Methods

Modifier and Type	Method and Description
abstract void	calculate(CalculationData data) Calculates one function with given data.
boolean	getProcessBuiltInFunctions() Whether built-in functions that have been supported by the built-in engine should be checked and processed by this implementation.
boolean	isParamArrayModeRequired() Indicates whether this engine needs the parameter to be calculated in array mode.
boolean	isParamLiteralRequired() Indicates whether this engine needs the literal text of parameter while doing calculation.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

AbstractCalculationEngine

public AbstractCalculationEngine()

Method Detail

calculate

public abstract void calculate(CalculationData data)

Calculates one function with given data.

Remarks

User should set the calculated value for given data for all functions(including excel native functions) that he wants to calculate by himself in this implementation.

Parameters:

data - the required data to calculate function such as function name, parameters, ...etc.

isParamLiteralRequired

public boolean isParamLiteralRequired()

Indicates whether this engine needs the literal text of parameter while doing calculation. Default value is false.

Remarks

If this custom calculation engine needs the parameter's literal text, more stacks will be required to cache the literal text for parameters and Calculate() method may be called recursively to calculate the parameter's value. Generally the literal text is not needed for calculating formulas and this property should be kept as false for most implementations to get better performance.

isParamArrayModeRequired

public boolean isParamArrayModeRequired()

Indicates whether this engine needs the parameter to be calculated in array mode. Default value is false. If CalculationData.getParamValueInArrayMode(int,int,int) is required when calculating custom functions, this property needs to be set as true.

Remarks

If this custom calculation engine needs the parameter to be calculated in array mode, more stacks will be required to cache the tree for parameters and Calculate() method may be called recursively to calculate the parameter's value. For performance consideration, if no special requirement, please keep this property as the default value(false).

getProcessBuiltInFunctions

public boolean getProcessBuiltInFunctions()

Whether built-in functions that have been supported by the built-in engine should be checked and processed by this implementation. Default is false. If user needs to change the calculation logic of some built-in functions, this property should be set as true. Otherwise please leave this property as false for performance consideration.