/*********************************************************************
*
* Copyright (C) 2002 Andrew Khan
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
***************************************************************************/
package jxl.biff.formula;
import java.util.Stack;
import jxl.common.Logger;
import jxl.WorkbookSettings;
import jxl.biff.IntegerHelper;
/**
* A built in function in a formula. These functions take a variable
* number of arguments, such as a range (eg. SUM etc)
*/
class VariableArgFunction extends Operator implements ParsedThing
{
/**
* The logger
*/
private static Logger logger = Logger.getLogger(VariableArgFunction.class);
/**
* The function
*/
private Function function;
/**
* The number of arguments
*/
private int arguments;
/**
* Flag which indicates whether this was initialized from the client
* api or from an excel sheet
*/
private boolean readFromSheet;
/**
* The workbooks settings
*/
private WorkbookSettings settings;
/**
* Constructor
*/
public VariableArgFunction(WorkbookSettings ws)
{
readFromSheet = true;
settings = ws;
}
/**
* Constructor used when parsing a function from a string
*
* @param f the function
* @param a the number of arguments
*/
public VariableArgFunction(Function f, int a, WorkbookSettings ws)
{
function = f;
arguments = a;
readFromSheet = false;
settings = ws;
}
/**
* Reads the ptg data from the array starting at the specified position
*
* @param data the RPN array
* @param pos the current position in the array, excluding the ptg identifier
* @return the number of bytes read
* @exception FormulaException
*/
public int read(byte[] data, int pos) throws FormulaException
{
arguments = data[pos];
int index = IntegerHelper.getInt(data[pos+1], data[pos+2]);
function = Function.getFunction(index);
if (function == Function.UNKNOWN)
{
throw new FormulaException(FormulaException.UNRECOGNIZED_FUNCTION,
index);
}
return 3;
}
/**
* Gets the operands for this operator from the stack
*/
public void getOperands(Stack s)
{
// parameters are in the correct order, god damn them
ParseItem[] items = new ParseItem[arguments];
for (int i = arguments - 1; i >= 0 ; i--)
{
ParseItem pi = (ParseItem) s.pop();
items[i] = pi;
}
for (int i = 0 ; i < arguments; i++)
{
add(items[i]);
}
}
public void getString(StringBuffer buf)
{
buf.append(function.getName(settings));
buf.append('(');
if (arguments > 0)
{
ParseItem[] operands = getOperands();
if (readFromSheet)
{
// arguments are in the same order they were specified
operands[0].getString(buf);
for (int i = 1; i < arguments; i++)
{
buf.append(',');
operands[i].getString(buf);
}
}
else
{
// arguments are stored in the reverse order to which they
// were specified, so iterate through them backwards
operands[arguments - 1].getString(buf);
for (int i = arguments - 2; i >= 0 ; i--)
{
buf.append(',');
operands[i].getString(buf);
}
}
}
buf.append(')');
}
/**
* Adjusts all the relative cell references in this formula by the
* amount specified. Used when copying formulas
*
* @param colAdjust the amount to add on to each relative cell reference
* @param rowAdjust the amount to add on to each relative row reference
*/
public void adjustRelativeCellReferences(int colAdjust, int rowAdjust)
{
ParseItem[] operands = getOperands();
for (int i = 0 ; i < operands.length ; i++)
{
operands[i].adjustRelativeCellReferences(colAdjust, rowAdjust);
}
}
/**
* Called when a column is inserted on the specified sheet. Tells
* the formula parser to update all of its cell references beyond this
* column
*
* @param sheetIndex the sheet on which the column was inserted
* @param col the column number which was inserted
* @param currentSheet TRUE if this formula is on the sheet in which the
* column was inserted, FALSE otherwise
*/
void columnInserted(int sheetIndex, int col, boolean currentSheet)
{
ParseItem[] operands = getOperands();
for (int i = 0 ; i < operands.length ; i++)
{
operands[i].columnInserted(sheetIndex, col, currentSheet);
}
}
/**
* Called when a column is inserted on the specified sheet. Tells
* the formula parser to update all of its cell references beyond this
* column
*
* @param sheetIndex the sheet on which the column was removed
* @param col the column number which was removed
* @param currentSheet TRUE if this formula is on the sheet in which the
* column was inserted, FALSE otherwise
*/
void columnRemoved(int sheetIndex, int col, boolean currentSheet)
{
ParseItem[] operands = getOperands();
for (int i = 0 ; i < operands.length ; i++)
{
operands[i].columnRemoved(sheetIndex, col, currentSheet);
}
}
/**
* Called when a column is inserted on the specified sheet. Tells
* the formula parser to update all of its cell references beyond this
* column
*
* @param sheetIndex the sheet on which the row was inserted
* @param row the row number which was inserted
* @param currentSheet TRUE if this formula is on the sheet in which the
* column was inserted, FALSE otherwise
*/
void rowInserted(int sheetIndex, int row, boolean currentSheet)
{
ParseItem[] operands = getOperands();
for (int i = 0 ; i < operands.length ; i++)
{
operands[i].rowInserted(sheetIndex, row, currentSheet);
}
}
/**
* Called when a column is inserted on the specified sheet. Tells
* the formula parser to update all of its cell references beyond this
* column
*
* @param sheetIndex the sheet on which the row was removed
* @param row the row number which was removed
* @param currentSheet TRUE if this formula is on the sheet in which the
* column was inserted, FALSE otherwise
*/
void rowRemoved(int sheetIndex, int row, boolean currentSheet)
{
ParseItem[] operands = getOperands();
for (int i = 0 ; i < operands.length ; i++)
{
operands[i].rowRemoved(sheetIndex, row, currentSheet);
}
}
/**
* If this formula was on an imported sheet, check that
* cell references to another sheet are warned appropriately
* Does nothing, as operators don't have cell references
*/
void handleImportedCellReferences()
{
ParseItem[] operands = getOperands();
for (int i = 0 ; i < operands.length ; i++)
{
operands[i].handleImportedCellReferences();
}
}
/**
* Gets the underlying function
*/
Function getFunction()
{
return function;
}
/**
* Gets the token representation of this item in RPN
*
* @return the bytes applicable to this formula
*/
byte[] getBytes()
{
handleSpecialCases();
// Get the data for the operands - in the correct order
ParseItem[] operands = getOperands();
byte[] data = new byte[0];
for (int i = 0 ; i < operands.length ; i++)
{
byte[] opdata = operands[i].getBytes();
// Grow the array
byte[] newdata = new byte[data.length + opdata.length];
System.arraycopy(data, 0, newdata, 0, data.length);
System.arraycopy(opdata, 0, newdata, data.length, opdata.length);
data = newdata;
}
// Add on the operator byte
byte[] newdata = new byte[data.length + 4];
System.arraycopy(data, 0, newdata, 0, data.length);
newdata[data.length] = !useAlternateCode() ?
Token.FUNCTIONVARARG.getCode() : Token.FUNCTIONVARARG.getCode2() ;
newdata[data.length+1] = (byte) arguments;
IntegerHelper.getTwoBytes(function.getCode(), newdata, data.length+2);
return newdata;
}
/**
* Gets the precedence for this operator. Operator precedents run from
* 1 to 5, one being the highest, 5 being the lowest
*
* @return the operator precedence
*/
int getPrecedence()
{
return 3;
}
/**
* Handles functions which form a special case
*/
private void handleSpecialCases()
{
// Handle the array functions. Tell all the Area records to
// use their alternative token code
if (function == Function.SUMPRODUCT)
{
// Get the data for the operands - in reverse order
ParseItem[] operands = getOperands();
for (int i = operands.length - 1 ; i >= 0 ; i--)
{
if (operands[i] instanceof Area)
{
operands[i].setAlternateCode();
}
}
}
}
}
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