Made BlankEval instance consistent with other Eval singletons.

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@885061 13f79535-47bb-0310-9956-ffa450edef68

src/java/org/apache/poi/hssf/record/formula/eval/BlankEval.java

@@ -23,7 +23,11 @@ package org.apache.poi.hssf.record.formula.eval;
  */
 public final class BlankEval implements ValueEval {
 
-	public static BlankEval INSTANCE = new BlankEval();
+	public static final BlankEval instance = new BlankEval();
+	/**
+	 * @deprecated (Nov 2009) use {@link #instance}
+	 */
+	public static final BlankEval INSTANCE = instance;
 
 	private BlankEval() {
 		// enforce singleton

src/java/org/apache/poi/hssf/record/formula/eval/ConcatEval.java

@@ -51,7 +51,7 @@ public final class ConcatEval  extends Fixed2ArgFunction {
 			StringValueEval sve = (StringValueEval) ve;
 			return sve.getStringValue();
 		}
-		if (ve == BlankEval.INSTANCE) {
+		if (ve == BlankEval.instance) {
 			return "";
 		}
 		throw new IllegalAccessError("Unexpected value type ("

src/java/org/apache/poi/hssf/record/formula/eval/OperandResolver.java

@@ -106,7 +106,7 @@ public final class OperandResolver {
 		if(result == null) {
 			// This seems to be required because AreaEval.values() array may contain nulls.
 			// perhaps that should not be allowed.
-			result = BlankEval.INSTANCE;
+			result = BlankEval.instance;
 		}
 		if (result instanceof ErrorEval) {
 			throw new EvaluationException((ErrorEval) result);
@@ -179,7 +179,7 @@ public final class OperandResolver {
 	 *
 	 */
 	public static int coerceValueToInt(ValueEval ev) throws EvaluationException {
-		if (ev == BlankEval.INSTANCE) {
+		if (ev == BlankEval.instance) {
 			return 0;
 		}
 		double d = coerceValueToDouble(ev);
@@ -201,7 +201,7 @@ public final class OperandResolver {
 	 */
 	public static double coerceValueToDouble(ValueEval ev) throws EvaluationException {
 
-		if (ev == BlankEval.INSTANCE) {
+		if (ev == BlankEval.instance) {
 			return 0.0;
 		}
 		if (ev instanceof NumericValueEval) {
@@ -268,7 +268,7 @@ public final class OperandResolver {
 			StringValueEval sve = (StringValueEval) ve;
 			return sve.getStringValue();
 		}
-		if (ve == BlankEval.INSTANCE) {
+		if (ve == BlankEval.instance) {
 			return "";
 		}
 		throw new IllegalArgumentException("Unexpected eval class (" + ve.getClass().getName() + ")");
@@ -280,7 +280,7 @@ public final class OperandResolver {
 	 */
 	public static Boolean coerceValueToBoolean(ValueEval ve, boolean stringsAreBlanks) throws EvaluationException {
 
-		if (ve == null || ve == BlankEval.INSTANCE) {
+		if (ve == null || ve == BlankEval.instance) {
 			// TODO - remove 've == null' condition once AreaEval is fixed
 			return null;
 		}
@@ -288,7 +288,7 @@ public final class OperandResolver {
 			return Boolean.valueOf(((BoolEval) ve).getBooleanValue());
 		}
 
-		if (ve == BlankEval.INSTANCE) {
+		if (ve == BlankEval.instance) {
 			return null;
 		}
 

src/java/org/apache/poi/hssf/record/formula/eval/RelationalOperationEval.java

@@ -73,10 +73,10 @@ public abstract class RelationalOperationEval extends Fixed2ArgFunction {
 
 	private static int doCompare(ValueEval va, ValueEval vb) {
 		// special cases when one operand is blank
-		if (va == BlankEval.INSTANCE) {
+		if (va == BlankEval.instance) {
 			return compareBlank(vb);
 		}
-		if (vb == BlankEval.INSTANCE) {
+		if (vb == BlankEval.instance) {
 			return -compareBlank(va);
 		}
 
@@ -117,7 +117,7 @@ public abstract class RelationalOperationEval extends Fixed2ArgFunction {
 	}
 
 	private static int compareBlank(ValueEval v) {
-		if (v == BlankEval.INSTANCE) {
+		if (v == BlankEval.instance) {
 			return 0;
 		}
 		if (v instanceof BoolEval) {

src/java/org/apache/poi/hssf/record/formula/functions/Choose.java

@@ -41,7 +41,7 @@ public final class Choose implements Function {
 			}
 			ValueEval result = OperandResolver.getSingleValue(args[ix], srcRowIndex, srcColumnIndex);
 			if (result == MissingArgEval.instance) {
-				return BlankEval.INSTANCE;
+				return BlankEval.instance;
 			}
 			return result;
 		} catch (EvaluationException e) {

src/java/org/apache/poi/hssf/record/formula/functions/Counta.java

@@ -62,7 +62,7 @@ public final class Counta implements Function {
 			// Error values like #VALUE!, #REF!, #DIV/0!, #NAME? etc don't cause this COUNTA to return an error
 			// in fact, they seem to get counted
 
-			if(valueEval == BlankEval.INSTANCE) {
+			if(valueEval == BlankEval.instance) {
 				return false;
 			}
 			// Note - everything but BlankEval counts

src/java/org/apache/poi/hssf/record/formula/functions/Countblank.java

@@ -54,7 +54,7 @@ public final class Countblank extends Fixed1ArgFunction {
 
 		public boolean matches(ValueEval valueEval) {
 			// Note - only BlankEval counts
-			return valueEval == BlankEval.INSTANCE;
+			return valueEval == BlankEval.instance;
 		}
 	};
 }

src/java/org/apache/poi/hssf/record/formula/functions/Countif.java

@@ -445,7 +445,7 @@ public final class Countif extends Fixed2ArgFunction {
 		if(evaluatedCriteriaArg instanceof ErrorEval) {
 			return new ErrorMatcher(((ErrorEval)evaluatedCriteriaArg).getErrorCode(), CmpOp.OP_NONE);
 		}
-		if(evaluatedCriteriaArg == BlankEval.INSTANCE) {
+		if(evaluatedCriteriaArg == BlankEval.instance) {
 			return null;
 		}
 		throw new RuntimeException("Unexpected type for criteria ("

src/java/org/apache/poi/hssf/record/formula/functions/If.java

@@ -38,7 +38,7 @@ public final class If extends Var2or3ArgFunction {
 		}
 		if (b) {
 			if (arg1 == MissingArgEval.instance) {
-				return BlankEval.INSTANCE;
+				return BlankEval.instance;
 			}
 			return arg1;
 		}
@@ -55,12 +55,12 @@ public final class If extends Var2or3ArgFunction {
 		}
 		if (b) {
 			if (arg1 == MissingArgEval.instance) {
-				return BlankEval.INSTANCE;
+				return BlankEval.instance;
 			}
 			return arg1;
 		}
 		if (arg2 == MissingArgEval.instance) {
-			return BlankEval.INSTANCE;
+			return BlankEval.instance;
 		}
 		return arg2;
 	}

src/java/org/apache/poi/hssf/record/formula/functions/Index.java

@@ -200,7 +200,7 @@ public final class Index implements Function2Arg, Function3Arg, Function4Arg {
 		if (ev == MissingArgEval.instance) {
 			return 0;
 		}
-		if (ev == BlankEval.INSTANCE) {
+		if (ev == BlankEval.instance) {
 			return 0;
 		}
 		int result = OperandResolver.coerceValueToInt(ev);

src/java/org/apache/poi/hssf/record/formula/functions/Indirect.java

@@ -80,7 +80,7 @@ public final class Indirect implements FreeRefFunction {
 			throws EvaluationException {
 		ValueEval ve = OperandResolver.getSingleValue(arg, ec.getRowIndex(), ec.getColumnIndex());
 
-		if (ve == BlankEval.INSTANCE || ve == MissingArgEval.instance) {
+		if (ve == BlankEval.instance || ve == MissingArgEval.instance) {
 			return false;
 		}
 		// numeric quantities follow standard boolean conversion rules

src/java/org/apache/poi/hssf/record/formula/functions/LookupUtils.java

@@ -585,7 +585,7 @@ final class LookupUtils {
 
 	public static LookupValueComparer createLookupComparer(ValueEval lookupValue) {
 
-		if (lookupValue == BlankEval.INSTANCE) {
+		if (lookupValue == BlankEval.instance) {
 			// blank eval translates to zero
 			// Note - a blank eval in the lookup column/row never matches anything
 			// empty string in the lookup column/row can only be matched by explicit empty string

src/java/org/apache/poi/hssf/record/formula/functions/Mode.java

@@ -118,7 +118,7 @@ public final class Mode implements Function {
 		if (arg instanceof ErrorEval) {
 			throw new EvaluationException((ErrorEval) arg);
 		}
-		if (arg == BlankEval.INSTANCE || arg instanceof BoolEval || arg instanceof StringEval) {
+		if (arg == BlankEval.instance || arg instanceof BoolEval || arg instanceof StringEval) {
 			if (mustBeNumber) {
 				throw EvaluationException.invalidValue();
 			}

src/java/org/apache/poi/hssf/record/formula/functions/MultiOperandNumericFunction.java

@@ -185,7 +185,7 @@ public abstract class MultiOperandNumericFunction implements Function {
 			}
 			return;
 		}
-		if (ve == BlankEval.INSTANCE) {
+		if (ve == BlankEval.instance) {
 			if (_isBlankCounted) {
 				temp.add(0.0);
 			}

src/java/org/apache/poi/ss/formula/CellCacheEntry.java

@@ -30,10 +30,10 @@ import org.apache.poi.ss.formula.IEvaluationListener.ICacheEntry;
  */
 abstract class CellCacheEntry implements ICacheEntry {
 	public static final CellCacheEntry[] EMPTY_ARRAY = { };
-	
+
 	private final FormulaCellCacheEntrySet _consumingCells;
 	private ValueEval _value;
-	
+
 
 	protected CellCacheEntry() {
 		_consumingCells = new FormulaCellCacheEntrySet();
@@ -53,7 +53,7 @@ abstract class CellCacheEntry implements ICacheEntry {
 	public final ValueEval getValue() {
 		return _value;
 	}
-	
+
 	private static boolean areValuesEqual(ValueEval a, ValueEval b) {
 		if (a == null) {
 			return false;
@@ -63,7 +63,7 @@ abstract class CellCacheEntry implements ICacheEntry {
 			// value type is changing
 			return false;
 		}
-		if (a == BlankEval.INSTANCE) {
+		if (a == BlankEval.instance) {
 			return b == a;
 		}
 		if (cls == NumberEval.class) {
@@ -83,7 +83,7 @@ abstract class CellCacheEntry implements ICacheEntry {
 
 	public final void addConsumingCell(FormulaCellCacheEntry cellLoc) {
 		_consumingCells.add(cellLoc);
-		
+
 	}
 	public final FormulaCellCacheEntry[] getConsumingCells() {
 		return _consumingCells.toArray();
@@ -102,23 +102,23 @@ abstract class CellCacheEntry implements ICacheEntry {
 			recurseClearCachedFormulaResults(listener, 1);
 		}
 	}
-	
+
 	/**
-	 * Calls formulaCell.setFormulaResult(null, null) recursively all the way up the tree of 
+	 * Calls formulaCell.setFormulaResult(null, null) recursively all the way up the tree of
 	 * dependencies. Calls usedCell.clearConsumingCell(fc) for each child of a cell that is
 	 * cleared along the way.
 	 * @param formulaCells
 	 */
 	protected final void recurseClearCachedFormulaResults() {
 		FormulaCellCacheEntry[] formulaCells = getConsumingCells();
-		
+
 		for (int i = 0; i < formulaCells.length; i++) {
 			FormulaCellCacheEntry fc = formulaCells[i];
 			fc.clearFormulaEntry();
 			fc.recurseClearCachedFormulaResults();
 		}
 	}
-	
+
 	/**
 	 * Identical to {@link #recurseClearCachedFormulaResults()} except for the listener call-backs
 	 */
@@ -133,5 +133,4 @@ abstract class CellCacheEntry implements ICacheEntry {
 			fc.recurseClearCachedFormulaResults(listener, depth+1);
 		}
 	}
-	
+}
-}

src/java/org/apache/poi/ss/formula/EvaluationCache.java

@@ -31,10 +31,9 @@ import org.apache.poi.ss.formula.PlainCellCache.Loc;
 
 /**
  * Performance optimisation for {@link HSSFFormulaEvaluator}. This class stores previously
- * calculated values of already visited cells, to avoid unnecessary re-calculation when the 
+ * calculated values of already visited cells, to avoid unnecessary re-calculation when the
  * same cells are referenced multiple times
- * 
+ *
- * 
  * @author Josh Micich
  */
 final class EvaluationCache {
@@ -84,7 +83,7 @@ final class EvaluationCache {
 		} else {
 			ValueEval value = WorkbookEvaluator.getValueFromNonFormulaCell(cell);
 			if (pcce == null) {
-				if (value != BlankEval.INSTANCE) {
+				if (value != BlankEval.instance) {
 					// only cache non-blank values in the plain cell cache
 					// (dependencies on blank cells are managed by
 					// FormulaCellCacheEntry._usedBlankCellGroup)
@@ -102,7 +101,7 @@ final class EvaluationCache {
 				if (pcce.updateValue(value)) {
 					pcce.recurseClearCachedFormulaResults(_evaluationListener);
 				}
-				if (value == BlankEval.INSTANCE) {
+				if (value == BlankEval.instance) {
 					_plainCellCache.remove(loc);
 				}
 			}
@@ -117,7 +116,7 @@ final class EvaluationCache {
 		}
 	}
 
-	private void updateAnyBlankReferencingFormulas(int bookIndex, int sheetIndex, 
+	private void updateAnyBlankReferencingFormulas(int bookIndex, int sheetIndex,
 			final int rowIndex, final int columnIndex) {
 		final BookSheetKey bsk = new BookSheetKey(bookIndex, sheetIndex);
 		_formulaCellCache.applyOperation(new IEntryOperation() {
@@ -130,7 +129,7 @@ final class EvaluationCache {
 
 	public PlainValueCellCacheEntry getPlainValueEntry(int bookIndex, int sheetIndex,
 			int rowIndex, int columnIndex, ValueEval value) {
-		
+
 		Loc loc = new Loc(bookIndex, sheetIndex, rowIndex, columnIndex);
 		PlainValueCellCacheEntry result = _plainCellCache.get(loc);
 		if (result == null) {
@@ -140,7 +139,7 @@ final class EvaluationCache {
 				_evaluationListener.onReadPlainValue(sheetIndex, rowIndex, columnIndex, result);
 			}
 		} else {
-			// TODO - if we are confident that this sanity check is not required, we can remove 'value' from plain value cache entry  
+			// TODO - if we are confident that this sanity check is not required, we can remove 'value' from plain value cache entry
 			if (!areValuesEqual(result.getValue(), value)) {
 				throw new IllegalStateException("value changed");
 			}
@@ -159,7 +158,7 @@ final class EvaluationCache {
 			// value type is changing
 			return false;
 		}
-		if (a == BlankEval.INSTANCE) {
+		if (a == BlankEval.instance) {
 			return b == a;
 		}
 		if (cls == NumberEval.class) {
@@ -176,11 +175,11 @@ final class EvaluationCache {
 		}
 		throw new IllegalStateException("Unexpected value class (" + cls.getName() + ")");
 	}
-	
+
 	public FormulaCellCacheEntry getOrCreateFormulaCellEntry(EvaluationCell cell) {
 		FormulaCellCacheEntry result = _formulaCellCache.get(cell);
 		if (result == null) {
-			
+
 			result = new FormulaCellCacheEntry();
 			_formulaCellCache.put(cell, result);
 		}
@@ -198,11 +197,11 @@ final class EvaluationCache {
 		_formulaCellCache.clear();
 	}
 	public void notifyDeleteCell(int bookIndex, int sheetIndex, EvaluationCell cell) {
-		
+
 		if (cell.getCellType() == HSSFCell.CELL_TYPE_FORMULA) {
 			FormulaCellCacheEntry fcce = _formulaCellCache.remove(cell);
 			if (fcce == null) {
-				// formula cell has not been evaluated yet 
+				// formula cell has not been evaluated yet
 			} else {
 				fcce.setSensitiveInputCells(null);
 				fcce.recurseClearCachedFormulaResults(_evaluationListener);
@@ -210,7 +209,7 @@ final class EvaluationCache {
 		} else {
 			Loc loc = new Loc(bookIndex, sheetIndex, cell.getRowIndex(), cell.getColumnIndex());
 			PlainValueCellCacheEntry pcce = _plainCellCache.get(loc);
-			
+
 			if (pcce == null) {
 				// cache entry doesn't exist. nothing to do
 			} else {

src/java/org/apache/poi/ss/formula/EvaluationTracker.java

@@ -84,7 +84,7 @@ final class EvaluationTracker {
 		if (result == ErrorEval.CIRCULAR_REF_ERROR && nFrames > 1) {
 			// Don't cache a circular ref error result if this cell is not the top evaluated cell.
 			// A true circular ref error will propagate all the way around the loop.  However, it's
-			// possible to have parts of the formula tree (/ parts of the loop) to evaluate to 
+			// possible to have parts of the formula tree (/ parts of the loop) to evaluate to
 			// CIRCULAR_REF_ERROR, and that value not get used in the final cell result (see the
 			// unit tests for a simple example). Thus, the only CIRCULAR_REF_ERROR result that can
 			// safely be cached is that of the top evaluated cell.
@@ -140,7 +140,7 @@ final class EvaluationTracker {
 			// Top level frame, there is no 'cell' above this frame that is using the current cell
 		} else {
 			CellEvaluationFrame consumingFrame = _evaluationFrames.get(prevFrameIndex);
-			if (value == BlankEval.INSTANCE) {
+			if (value == BlankEval.instance) {
 				consumingFrame.addUsedBlankCell(bookIndex, sheetIndex, rowIndex, columnIndex);
 			} else {
 				PlainValueCellCacheEntry cce = _cache.getPlainValueEntry(bookIndex, sheetIndex,

src/java/org/apache/poi/ss/formula/WorkbookEvaluator.java

@@ -313,7 +313,7 @@ public final class WorkbookEvaluator {
 	 */
 	/* package */ static ValueEval getValueFromNonFormulaCell(EvaluationCell cell) {
 		if (cell == null) {
-			return BlankEval.INSTANCE;
+			return BlankEval.instance;
 		}
 		int cellType = cell.getCellType();
 		switch (cellType) {
@@ -324,7 +324,7 @@ public final class WorkbookEvaluator {
 			case Cell.CELL_TYPE_BOOLEAN:
 				return BoolEval.valueOf(cell.getBooleanCellValue());
 			case Cell.CELL_TYPE_BLANK:
-				return BlankEval.INSTANCE;
+				return BlankEval.instance;
 			case Cell.CELL_TYPE_ERROR:
 				return ErrorEval.valueOf(cell.getErrorCellValue());
 		}
@@ -401,7 +401,7 @@ public final class WorkbookEvaluator {
 					i+= countTokensToBeSkipped(ptgs, i, dist);
 					if (stack.peek() == MissingArgEval.instance) {
 						stack.pop();
-						stack.push(BlankEval.INSTANCE);
+						stack.push(BlankEval.instance);
 					}
 					continue;
 				}
@@ -450,7 +450,7 @@ public final class WorkbookEvaluator {
 			throw new IllegalStateException("evaluation stack not empty");
 		}
 		value = dereferenceValue(value, ec.getRowIndex(), ec.getColumnIndex());
-		if (value == BlankEval.INSTANCE) {
+		if (value == BlankEval.instance) {
 			// Note Excel behaviour here. A blank final final value is converted to zero.
 			return NumberEval.ZERO;
 			// Formulas _never_ evaluate to blank.  If a formula appears to have evaluated to

src/java/org/apache/poi/ss/formula/eval/forked/ForkedEvaluationCell.java

@@ -49,7 +49,7 @@ final class ForkedEvaluationCell implements EvaluationCell {
 		_sheet = sheet;
 		_masterCell = masterCell;
 		// start with value blank, but expect construction to be immediately
-		setValue(BlankEval.INSTANCE); // followed by a proper call to setValue()
+		setValue(BlankEval.instance); // followed by a proper call to setValue()
 	}
 
 	public Object getIdentityKey() {

src/testcases/org/apache/poi/hssf/record/formula/eval/TestEqualEval.java

@@ -59,7 +59,7 @@ public final class TestEqualEval extends TestCase {
 
 		ValueEval[] args = {
 			new StringEval(""),
-			BlankEval.INSTANCE,
+			BlankEval.instance,
 		};
 		ValueEval result = evaluate(EI.Equal, args, 10, 10);
 		assertEquals(BoolEval.class, result.getClass());

src/testcases/org/apache/poi/hssf/record/formula/functions/TestAverage.java

@@ -61,11 +61,11 @@ public final class TestAverage extends TestCase {
 		values = new ValueEval[] {
 				new NumberEval(1),
 				new NumberEval(2),
-				BlankEval.INSTANCE,
+				BlankEval.instance,
 				new NumberEval(3),
-				BlankEval.INSTANCE,
+				BlankEval.instance,
 				new NumberEval(4),
-				BlankEval.INSTANCE,
+				BlankEval.instance,
 		};
 
 		confirmAverage(values, 2.5);

src/testcases/org/apache/poi/hssf/record/formula/functions/TestCountFuncs.java

@@ -57,7 +57,7 @@ public final class TestCountFuncs extends TestCase {
 				BoolEval.TRUE,
 				BoolEval.FALSE,
 				ErrorEval.DIV_ZERO,
-				BlankEval.INSTANCE,
+				BlankEval.instance,
 		};
 		range = EvalFactory.createAreaEval("A1:B3", values);
 		confirmCountBlank(1, range);
@@ -65,10 +65,10 @@ public final class TestCountFuncs extends TestCase {
 		values = new ValueEval[] {
 				new NumberEval(0),
 				new StringEval(""),	// note - does not match blank
-				BlankEval.INSTANCE,
+				BlankEval.instance,
 				BoolEval.FALSE,
 				BoolEval.TRUE,
-				BlankEval.INSTANCE,
+				BlankEval.instance,
 		};
 		range = EvalFactory.createAreaEval("A1:B3", values);
 		confirmCountBlank(2, range);
@@ -116,7 +116,7 @@ public final class TestCountFuncs extends TestCase {
 				BoolEval.TRUE,
 				BoolEval.FALSE,
 				BoolEval.TRUE,
-				BlankEval.INSTANCE,
+				BlankEval.instance,
 		};
 		range = EvalFactory.createAreaEval("A1:B3", values);
 		confirmCountIf(2, range, BoolEval.TRUE);
@@ -414,7 +414,7 @@ public final class TestCountFuncs extends TestCase {
 		assertEquals(expectedResult, matchPredicate.matches(new NumberEval(value)));
 	}
 	private static void confirmPredicate(boolean expectedResult, I_MatchPredicate matchPredicate, String value) {
-		ValueEval ev = value == null ? BlankEval.INSTANCE : new StringEval(value);
+		ValueEval ev = value == null ? BlankEval.instance : new StringEval(value);
 		assertEquals(expectedResult, matchPredicate.matches(ev));
 	}
 	private static void confirmPredicate(boolean expectedResult, I_MatchPredicate matchPredicate, ErrorEval value) {

src/testcases/org/apache/poi/hssf/record/formula/functions/TestLen.java

@@ -63,7 +63,7 @@ public final class TestLen extends TestCase {
 		confirmLen(new NumberEval(123456), 6);
 		confirmLen(BoolEval.FALSE, 5);
 		confirmLen(BoolEval.TRUE, 4);
-		confirmLen(BlankEval.INSTANCE, 0);
+		confirmLen(BlankEval.instance, 0);
 	}
 
 	public void testErrors() {

src/testcases/org/apache/poi/hssf/record/formula/functions/TestMid.java

@@ -75,11 +75,11 @@ public final class TestMid extends TestCase {
 		RefEval reNumChars = EvalFactory.createRefEval("B1", new NumberEval(3));
 		confirmMid(new StringEval("galactic"), aeStart, reNumChars, "ala");
 
-		confirmMid(new StringEval("galactic"), new NumberEval(3.1), BlankEval.INSTANCE, "");
+		confirmMid(new StringEval("galactic"), new NumberEval(3.1), BlankEval.instance, "");
 
 		confirmMid(new StringEval("galactic"), new NumberEval(3), BoolEval.FALSE, "");
 		confirmMid(new StringEval("galactic"), new NumberEval(3), BoolEval.TRUE, "l");
-		confirmMid(BlankEval.INSTANCE, new NumberEval(3), BoolEval.TRUE, "");
+		confirmMid(BlankEval.instance, new NumberEval(3), BoolEval.TRUE, "");
 
 	}
 
@@ -102,7 +102,7 @@ public final class TestMid extends TestCase {
 		confirmMid(new StringEval("galactic"), new NumberEval(3), ErrorEval.NAME_INVALID, ErrorEval.NAME_INVALID);
 		confirmMid(new StringEval("galactic"), ErrorEval.DIV_ZERO, ErrorEval.NAME_INVALID, ErrorEval.DIV_ZERO);
 
-		confirmMid(new StringEval("galactic"), BlankEval.INSTANCE, new NumberEval(3.1), ErrorEval.VALUE_INVALID);
+		confirmMid(new StringEval("galactic"), BlankEval.instance, new NumberEval(3.1), ErrorEval.VALUE_INVALID);
 
 		confirmMid(new StringEval("galactic"), new NumberEval(0), new NumberEval(4), ErrorEval.VALUE_INVALID);
 		confirmMid(new StringEval("galactic"), new NumberEval(1), new NumberEval(-1), ErrorEval.VALUE_INVALID);

src/testcases/org/apache/poi/hssf/record/formula/functions/TestTFunc.java

@@ -94,7 +94,7 @@ public final class TestTFunc extends TestCase {
 	public void testOtherValues() {
 		confirmOther(new NumberEval(2));
 		confirmOther(BoolEval.FALSE);
-		confirmOther(BlankEval.INSTANCE);  // can this particular case be verified?
+		confirmOther(BlankEval.instance);  // can this particular case be verified?
 	}
 
 	public void testRefValues() {

src/testcases/org/apache/poi/hssf/record/formula/functions/TestTrim.java

@@ -69,7 +69,7 @@ public final class TestTrim extends TestCase {
 		confirmTrim(new NumberEval(123456), "123456");
 		confirmTrim(BoolEval.FALSE, "FALSE");
 		confirmTrim(BoolEval.TRUE, "TRUE");
-		confirmTrim(BlankEval.INSTANCE, "");
+		confirmTrim(BlankEval.instance, "");
 	}
 
 	public void testErrors() {

src/testcases/org/apache/poi/ss/formula/TestEvaluationCache.java

@@ -178,7 +178,7 @@ public class TestEvaluationCache extends TestCase {
 				BoolEval be = (BoolEval) value;
 				return be.getStringValue();
 			}
-			if (value == BlankEval.INSTANCE) {
+			if (value == BlankEval.instance) {
 				return "#BLANK#";
 			}
 			if (value instanceof ErrorEval) {