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package org.apache.poi.ss.formula.functions;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import org.apache.poi.ss.formula.TwoDEval;
import org.apache.poi.ss.formula.eval.BlankEval;
import org.apache.poi.ss.formula.eval.BoolEval;
import org.apache.poi.ss.formula.eval.ErrorEval;
import org.apache.poi.ss.formula.eval.EvaluationException;
import org.apache.poi.ss.formula.eval.MissingArgEval;
import org.apache.poi.ss.formula.eval.NumberEval;
import org.apache.poi.ss.formula.eval.NumericValueEval;
import org.apache.poi.ss.formula.eval.OperandResolver;
import org.apache.poi.ss.formula.eval.RefEval;
import org.apache.poi.ss.formula.eval.StringEval;
import org.apache.poi.ss.formula.eval.ValueEval;
/**
* Common functionality used by VLOOKUP, HLOOKUP, LOOKUP and MATCH
*/
final class LookupUtils {
/**
* Represents a single row or column within an AreaEval.
*/
public interface ValueVector {
ValueEval getItem(int index);
int getSize();
}
private static final class RowVector implements ValueVector {
private final TwoDEval _tableArray;
private final int _size;
private final int _rowIndex;
public RowVector(TwoDEval tableArray, int rowIndex) {
_rowIndex = rowIndex;
int lastRowIx = tableArray.getHeight() - 1;
if(rowIndex < 0 || rowIndex > lastRowIx) {
throw new IllegalArgumentException("Specified row index (" + rowIndex
+ ") is outside the allowed range (0.." + lastRowIx + ")");
}
_tableArray = tableArray;
_size = tableArray.getWidth();
}
public ValueEval getItem(int index) {
if(index > _size) {
throw new ArrayIndexOutOfBoundsException("Specified index (" + index
+ ") is outside the allowed range (0.." + (_size-1) + ")");
}
return _tableArray.getValue(_rowIndex, index);
}
public int getSize() {
return _size;
}
}
private static final class ColumnVector implements ValueVector {
private final TwoDEval _tableArray;
private final int _size;
private final int _columnIndex;
public ColumnVector(TwoDEval tableArray, int columnIndex) {
_columnIndex = columnIndex;
int lastColIx = tableArray.getWidth()-1;
if(columnIndex < 0 || columnIndex > lastColIx) {
throw new IllegalArgumentException("Specified column index (" + columnIndex
+ ") is outside the allowed range (0.." + lastColIx + ")");
}
_tableArray = tableArray;
_size = _tableArray.getHeight();
}
public ValueEval getItem(int index) {
if(index > _size) {
throw new ArrayIndexOutOfBoundsException("Specified index (" + index
+ ") is outside the allowed range (0.." + (_size-1) + ")");
}
return _tableArray.getValue(index, _columnIndex);
}
public int getSize() {
return _size;
}
}
private static final class SheetVector implements ValueVector {
private final RefEval _re;
private final int _size;
public SheetVector(RefEval re) {
_size = re.getNumberOfSheets();
_re = re;
}
public ValueEval getItem(int index) {
if(index >= _size) {
throw new ArrayIndexOutOfBoundsException("Specified index (" + index
+ ") is outside the allowed range (0.." + (_size-1) + ")");
}
int sheetIndex = _re.getFirstSheetIndex() + index;
return _re.getInnerValueEval(sheetIndex);
}
public int getSize() {
return _size;
}
}
public static ValueVector createRowVector(TwoDEval tableArray, int relativeRowIndex) {
return new RowVector(tableArray, relativeRowIndex);
}
public static ValueVector createColumnVector(TwoDEval tableArray, int relativeColumnIndex) {
return new ColumnVector(tableArray, relativeColumnIndex);
}
/**
* @return null if the supplied area is neither a single row nor a single column
*/
public static ValueVector createVector(TwoDEval ae) {
if (ae.isColumn()) {
return createColumnVector(ae, 0);
}
if (ae.isRow()) {
return createRowVector(ae, 0);
}
return null;
}
public static ValueVector createVector(RefEval re) {
return new SheetVector(re);
}
/**
* Enumeration to support 4 valued comparison results.
* Excel lookup functions have complex behaviour in the case where the lookup array has mixed
* types, and/or is unordered. Contrary to suggestions in some Excel documentation, there
* does not appear to be a universal ordering across types. The binary search algorithm used
* changes behaviour when the evaluated 'mid' value has a different type to the lookup value.
*
* A simple int might have done the same job, but there is risk in confusion with the well
* known Comparable.compareTo() and Comparator.compare() which both use
* a ubiquitous 3 value result encoding.
*/
public static final class CompareResult {
private final boolean _isTypeMismatch;
private final boolean _isLessThan;
private final boolean _isEqual;
private final boolean _isGreaterThan;
private CompareResult(boolean isTypeMismatch, int simpleCompareResult) {
if(isTypeMismatch) {
_isTypeMismatch = true;
_isLessThan = false;
_isEqual = false;
_isGreaterThan = false;
} else {
_isTypeMismatch = false;
_isLessThan = simpleCompareResult < 0;
_isEqual = simpleCompareResult == 0;
_isGreaterThan = simpleCompareResult > 0;
}
}
public static final CompareResult TYPE_MISMATCH = new CompareResult(true, 0);
public static final CompareResult LESS_THAN = new CompareResult(false, -1);
public static final CompareResult EQUAL = new CompareResult(false, 0);
public static final CompareResult GREATER_THAN = new CompareResult(false, +1);
public static CompareResult valueOf(int simpleCompareResult) {
if(simpleCompareResult < 0) {
return LESS_THAN;
}
if(simpleCompareResult > 0) {
return GREATER_THAN;
}
return EQUAL;
}
public static CompareResult valueOf(boolean matches) {
if(matches) {
return EQUAL ;
}
return LESS_THAN;
}
public boolean isTypeMismatch() {
return _isTypeMismatch;
}
public boolean isLessThan() {
return _isLessThan;
}
public boolean isEqual() {
return _isEqual;
}
public boolean isGreaterThan() {
return _isGreaterThan;
}
public String toString() {
return getClass().getName() + " [" +
formatAsString() +
"]";
}
private String formatAsString() {
if(_isTypeMismatch) {
return "TYPE_MISMATCH";
}
if(_isLessThan) {
return "LESS_THAN";
}
if(_isEqual) {
return "EQUAL";
}
if(_isGreaterThan) {
return "GREATER_THAN";
}
// toString must be reliable
return "??error??";
}
}
public interface LookupValueComparer {
/**
* @return one of 4 instances or CompareResult: LESS_THAN, EQUAL,
* GREATER_THAN or TYPE_MISMATCH
*/
CompareResult compareTo(ValueEval other);
}
private static abstract class LookupValueComparerBase implements LookupValueComparer {
private final Class _targetClass;
protected LookupValueComparerBase(ValueEval targetValue) {
if(targetValue == null) {
throw new RuntimeException("targetValue cannot be null");
}
_targetClass = targetValue.getClass();
}
public final CompareResult compareTo(ValueEval other) {
if (other == null) {
throw new RuntimeException("compare to value cannot be null");
}
if (_targetClass != other.getClass()) {
return CompareResult.TYPE_MISMATCH;
}
return compareSameType(other);
}
public String toString() {
return getClass().getName() + " [" +
getValueAsString() +
"]";
}
protected abstract CompareResult compareSameType(ValueEval other);
/** used only for debug purposes */
protected abstract String getValueAsString();
}
private static final class StringLookupComparer extends LookupValueComparerBase {
private final String _value;
private final Pattern _wildCardPattern;
private final boolean _matchExact;
private final boolean _isMatchFunction;
protected StringLookupComparer(StringEval se, boolean matchExact, boolean isMatchFunction) {
super(se);
_value = se.getStringValue();
_wildCardPattern = Countif.StringMatcher.getWildCardPattern(_value);
_matchExact = matchExact;
_isMatchFunction = isMatchFunction;
}
protected CompareResult compareSameType(ValueEval other) {
StringEval se = (StringEval) other;
String stringValue = se.getStringValue();
if (_wildCardPattern != null) {
Matcher matcher = _wildCardPattern.matcher(stringValue);
boolean matches = matcher.matches();
if (_isMatchFunction ||
!_matchExact) {
return CompareResult.valueOf(matches);
}
}
return CompareResult.valueOf(_value.compareToIgnoreCase(stringValue));
}
protected String getValueAsString() {
return _value;
}
}
private static final class NumberLookupComparer extends LookupValueComparerBase {
private final double _value;
protected NumberLookupComparer(NumberEval ne) {
super(ne);
_value = ne.getNumberValue();
}
protected CompareResult compareSameType(ValueEval other) {
NumberEval ne = (NumberEval) other;
return CompareResult.valueOf(Double.compare(_value, ne.getNumberValue()));
}
protected String getValueAsString() {
return String.valueOf(_value);
}
}
private static final class BooleanLookupComparer extends LookupValueComparerBase {
private final boolean _value;
protected BooleanLookupComparer(BoolEval be) {
super(be);
_value = be.getBooleanValue();
}
protected CompareResult compareSameType(ValueEval other) {
BoolEval be = (BoolEval) other;
boolean otherVal = be.getBooleanValue();
if(_value == otherVal) {
return CompareResult.EQUAL;
}
// TRUE > FALSE
if(_value) {
return CompareResult.GREATER_THAN;
}
return CompareResult.LESS_THAN;
}
protected String getValueAsString() {
return String.valueOf(_value);
}
}
/**
* Processes the third argument to VLOOKUP, or HLOOKUP (col_index_num
* or row_index_num respectively).
* Sample behaviour:
*
* Input Return Value Thrown Error 5 4 2.9 2 "5" 4 "2.18e1" 21 "-$2" -3 * FALSE -1 * TRUE 0 "TRUE" #REF! "abc" #REF! "" #REF! <blank> #VALUE!
*
* Note - out of range errors (result index too high) are handled by the caller.
* @return column or row index as a zero-based value, never negative.
* @throws EvaluationException when the specified arg cannot be coerced to a non-negative integer
*/
public static int resolveRowOrColIndexArg(ValueEval rowColIndexArg, int srcCellRow, int srcCellCol) throws EvaluationException {
if(rowColIndexArg == null) {
throw new IllegalArgumentException("argument must not be null");
}
ValueEval veRowColIndexArg;
try {
veRowColIndexArg = OperandResolver.getSingleValue(rowColIndexArg, srcCellRow, (short)srcCellCol);
} catch (EvaluationException e) {
// All errors get translated to #REF!
throw EvaluationException.invalidRef();
}
int oneBasedIndex;
if(veRowColIndexArg instanceof StringEval) {
StringEval se = (StringEval) veRowColIndexArg;
String strVal = se.getStringValue();
Double dVal = OperandResolver.parseDouble(strVal);
if(dVal == null) {
// String does not resolve to a number. Raise #REF! error.
throw EvaluationException.invalidRef();
// This includes text booleans "TRUE" and "FALSE". They are not valid.
}
// else - numeric value parses OK
}
// actual BoolEval values get interpreted as FALSE->0 and TRUE->1
oneBasedIndex = OperandResolver.coerceValueToInt(veRowColIndexArg);
if (oneBasedIndex < 1) {
// note this is asymmetric with the errors when the index is too large (#REF!)
throw EvaluationException.invalidValue();
}
return oneBasedIndex - 1; // convert to zero based
}
/**
* The second argument (table_array) should be an area ref, but can actually be a cell ref, in
* which case it is interpreted as a 1x1 area ref. Other scalar values cause #VALUE! error.
*/
public static TwoDEval resolveTableArrayArg(ValueEval eval) throws EvaluationException {
if (eval instanceof TwoDEval) {
return (TwoDEval) eval;
}
if(eval instanceof RefEval) {
RefEval refEval = (RefEval) eval;
// Make this cell ref look like a 1x1 area ref.
// It doesn't matter if eval is a 2D or 3D ref, because that detail is never asked of AreaEval.
return refEval.offset(0, 0, 0, 0);
}
throw EvaluationException.invalidValue();
}
/**
* Resolves the last (optional) parameter (range_lookup) to the VLOOKUP and HLOOKUP functions.
* @param rangeLookupArg must not be null
*/
public static boolean resolveRangeLookupArg(ValueEval rangeLookupArg, int srcCellRow, int srcCellCol) throws EvaluationException {
ValueEval valEval = OperandResolver.getSingleValue(rangeLookupArg, srcCellRow, srcCellCol);
if(valEval == MissingArgEval.instance) {
// Tricky:
// forth arg exists but is not supplied: "=VLOOKUP(A1,A2:A4,2,)"
return false;
}
if(valEval instanceof BlankEval) {
// Tricky:
// fourth arg supplied but evaluates to blank
// this does not get the default value
return false;
}
if(valEval instanceof BoolEval) {
// Happy day flow
BoolEval boolEval = (BoolEval) valEval;
return boolEval.getBooleanValue();
}
if (valEval instanceof StringEval) {
String stringValue = ((StringEval) valEval).getStringValue();
if(stringValue.length() < 1) {
// More trickiness:
// Empty string is not the same as BlankEval. It causes #VALUE! error
throw EvaluationException.invalidValue();
}
// TODO move parseBoolean to OperandResolver
Boolean b = Countif.parseBoolean(stringValue);
if(b != null) {
// string converted to boolean OK
return b;
}
// Even more trickiness:
// Note - even if the StringEval represents a number value (for example "1"),
// Excel does not resolve it to a boolean.
throw EvaluationException.invalidValue();
// This is in contrast to the code below,, where NumberEvals values (for
// example 0.01) *do* resolve to equivalent boolean values.
}
if (valEval instanceof NumericValueEval) {
NumericValueEval nve = (NumericValueEval) valEval;
// zero is FALSE, everything else is TRUE
return 0.0 != nve.getNumberValue();
}
throw new RuntimeException("Unexpected eval type (" + valEval + ")");
}
public static int lookupIndexOfValue(ValueEval lookupValue, ValueVector vector, boolean isRangeLookup) throws EvaluationException {
LookupValueComparer lookupComparer = createLookupComparer(lookupValue, isRangeLookup, false);
int result;
if(isRangeLookup) {
result = performBinarySearch(vector, lookupComparer);
} else {
result = lookupIndexOfExactValue(lookupComparer, vector);
}
if(result < 0) {
throw new EvaluationException(ErrorEval.NA);
}
return result;
}
/**
* Finds first (lowest index) exact occurrence of specified value.
* @param lookupComparer the value to be found in column or row vector
* @param vector the values to be searched. For VLOOKUP this is the first column of the
* tableArray. For HLOOKUP this is the first row of the tableArray.
* @return zero based index into the vector, -1 if value cannot be found
*/
private static int lookupIndexOfExactValue(LookupValueComparer lookupComparer, ValueVector vector) {
// find first occurrence of lookup value
int size = vector.getSize();
for (int i = 0; i < size; i++) {
if(lookupComparer.compareTo(vector.getItem(i)).isEqual()) {
return i;
}
}
return -1;
}
/**
* Encapsulates some standard binary search functionality so the unusual Excel behaviour can
* be clearly distinguished.
*/
private static final class BinarySearchIndexes {
private int _lowIx;
private int _highIx;
public BinarySearchIndexes(int highIx) {
_lowIx = -1;
_highIx = highIx;
}
/**
* @return -1 if the search range is empty
*/
public int getMidIx() {
int ixDiff = _highIx - _lowIx;
if(ixDiff < 2) {
return -1;
}
return _lowIx + (ixDiff / 2);
}
public int getLowIx() {
return _lowIx;
}
public int getHighIx() {
return _highIx;
}
public void narrowSearch(int midIx, boolean isLessThan) {
if(isLessThan) {
_highIx = midIx;
} else {
_lowIx = midIx;
}
}
}
/**
* Excel has funny behaviour when the some elements in the search vector are the wrong type.
*
*/
private static int performBinarySearch(ValueVector vector, LookupValueComparer lookupComparer) {
// both low and high indexes point to values assumed too low and too high.
BinarySearchIndexes bsi = new BinarySearchIndexes(vector.getSize());
while(true) {
int midIx = bsi.getMidIx();
if(midIx < 0) {
return bsi.getLowIx();
}
CompareResult cr = lookupComparer.compareTo(vector.getItem(midIx));
if(cr.isTypeMismatch()) {
int newMidIx = handleMidValueTypeMismatch(lookupComparer, vector, bsi, midIx);
if(newMidIx < 0) {
continue;
}
midIx = newMidIx;
cr = lookupComparer.compareTo(vector.getItem(midIx));
}
if(cr.isEqual()) {
return findLastIndexInRunOfEqualValues(lookupComparer, vector, midIx, bsi.getHighIx());
}
bsi.narrowSearch(midIx, cr.isLessThan());
}
}
/**
* Excel seems to handle mismatched types initially by just stepping 'mid' ix forward to the
* first compatible value.
* @param midIx 'mid' index (value which has the wrong type)
* @return usually -1, signifying that the BinarySearchIndex has been narrowed to the new mid
* index. Zero or greater signifies that an exact match for the lookup value was found
*/
private static int handleMidValueTypeMismatch(LookupValueComparer lookupComparer, ValueVector vector,
BinarySearchIndexes bsi, int midIx) {
int newMid = midIx;
int highIx = bsi.getHighIx();
while(true) {
newMid++;
if(newMid == highIx) {
// every element from midIx to highIx was the wrong type
// move highIx down to the low end of the mid values
bsi.narrowSearch(midIx, true);
return -1;
}
CompareResult cr = lookupComparer.compareTo(vector.getItem(newMid));
if(cr.isLessThan() && newMid == highIx-1) {
// move highIx down to the low end of the mid values
bsi.narrowSearch(midIx, true);
return -1;
// but only when "newMid == highIx-1"? slightly weird.
// It would seem more efficient to always do this.
}
if(cr.isTypeMismatch()) {
// keep stepping over values until the right type is found
continue;
}
if(cr.isEqual()) {
return newMid;
}
// Note - if moving highIx down (due to lookup