private void validateNumArgs(int numArgs, FunctionMetadata fm) {
if (numArgs < fm.getMinParams()) {
String msg = "Too few arguments to function '" + fm.getName() + "'. ";
if (fm.hasFixedArgsLength()) {
msg += "Expected " + fm.getMinParams();
} else {
msg += "At least " + fm.getMinParams() + " were expected";
}
msg += " but got " + numArgs + ".";
throw new FormulaParseException(msg);
}
// the maximum number of arguments depends on the Excel version
int maxArgs;
if (fm.hasUnlimitedVarags()) {
if (_book != null) {
maxArgs = _book.getSpreadsheetVersion().getMaxFunctionArgs();
} else {
// _book can be omitted by test cases
maxArgs = fm.getMaxParams(); // just use BIFF8
}
} else {
maxArgs = fm.getMaxParams();
}
if (numArgs > maxArgs) {
String msg = "Too many arguments to function '" + fm.getName() + "'. ";
if (fm.hasFixedArgsLength()) {
msg += "Expected " + maxArgs;
} else {
msg += "At most " + maxArgs + " were expected";
}
msg += " but got " + numArgs + ".";
throw new FormulaParseException(msg);
}
}
/**
* Generates the variable function ptg for the formula.
*
* <p>For IF Formulas, additional PTGs are added to the tokens
*
* @param name a {@link NamePtg} or {@link NameXPtg} or <code>null</code>
* @return Ptg a null is returned if we're in an IF formula, it needs extreme manipulation and is
* handled in this function
*/
private ParseNode getFunction(String name, Ptg namePtg, ParseNode[] args) {
FunctionMetadata fm = FunctionMetadataRegistry.getFunctionByName(name.toUpperCase());
int numArgs = args.length;
if (fm == null) {
if (namePtg == null) {
throw new IllegalStateException("NamePtg must be supplied for external functions");
}
// must be external function
ParseNode[] allArgs = new ParseNode[numArgs + 1];
allArgs[0] = new ParseNode(namePtg);
System.arraycopy(args, 0, allArgs, 1, numArgs);
return new ParseNode(new FuncVarPtg(name, (byte) (numArgs + 1)), allArgs);
}
if (namePtg != null) {
throw new IllegalStateException("NamePtg no applicable to internal functions");
}
boolean isVarArgs = !fm.hasFixedArgsLength();
int funcIx = fm.getIndex();
if (funcIx == FunctionMetadataRegistry.FUNCTION_INDEX_SUM && args.length == 1) {
// Excel encodes the sum of a single argument as tAttrSum
// POI does the same for consistency, but this is not critical
return new ParseNode(AttrPtg.getSumSingle(), args);
// The code below would encode tFuncVar(SUM) which seems to do no harm
}
validateNumArgs(args.length, fm);
AbstractFunctionPtg retval;
if (isVarArgs) {
retval = new FuncVarPtg(name, (byte) numArgs);
} else {
retval = new FuncPtg(funcIx);
}
return new ParseNode(retval, args);
}