Bugzilla 47969 - improvements to equals() methods

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@824972 13f79535-47bb-0310-9956-ffa450edef68

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

@@ -43,6 +43,7 @@ final class FormulaUsedBlankCellSet {
 			return _bookIndex * 17 + _sheetIndex;
 		}
 		public boolean equals(Object obj) {
+			assert obj instanceof BookSheetKey : "these private cache key instances are only compared to themselves";
 			BookSheetKey other = (BookSheetKey) obj;
 			return _bookIndex == other._bookIndex && _sheetIndex == other._sheetIndex;
 		}

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

@@ -52,6 +52,7 @@ final class PlainCellCache {
 		}
 
 		public boolean equals(Object obj) {
+			assert obj instanceof Loc : "these package-private cache key instances are only compared to themselves";
 			Loc other = (Loc) obj;
 			return _bookSheetColumn == other._bookSheetColumn && _rowIndex == other._rowIndex;
 		}

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

@@ -111,6 +111,7 @@ final class ForkedEvaluationSheet implements EvaluationSheet {
 		}
 		@Override
 		public boolean equals(Object obj) {
+			assert obj instanceof RowColKey : "these private cache key instances are only compared to themselves";
 			RowColKey other = (RowColKey) obj;
 			return _rowIndex == other._rowIndex && _columnIndex == other._columnIndex;
 		}

src/java/org/apache/poi/ss/util/MutableFPNumber.java

@@ -93,14 +93,6 @@ final class MutableFPNumber {
 
 	}
 
-	@Override
-	public boolean equals(Object obj) {
-		MutableFPNumber other = (MutableFPNumber) obj;
-		if (_binaryExponent != other._binaryExponent) {
-			return false;
-		}
-		return _significand.equals(other._significand);
-	}
 	public boolean isBelowMaxRep() {
 		int sc = _significand.bitLength() - C_64;
 		return _significand.compareTo(BI_MAX_BASE.shiftLeft(sc)) < 0;