Added implementation for ISNA()

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@786696 13f79535-47bb-0310-9956-ffa450edef68

src/documentation/content/xdocs/status.xml

@@ -33,6 +33,7 @@
 
     <changes>
         <release version="3.5-beta7" date="2009-??-??">
+           <action dev="POI-DEVELOPERS" type="add">Added implementation for ISNA()</action>
            <action dev="POI-DEVELOPERS" type="add">46793 - fixed SimpleShape#getLineWidth to handle default line width </action>
            <action dev="POI-DEVELOPERS" type="add">47356 - removed unused private fields in HWPF BorderCode</action>
            <action dev="POI-DEVELOPERS" type="add">47355 - Improved  HWPF TableCell to expose TableCellDescriptor</action>

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

@@ -26,7 +26,6 @@ import org.apache.poi.hssf.record.formula.functions.*;
 
 /**
  * @author Amol S. Deshmukh < amolweb at ya hoo dot com >
- *  
  */
 public abstract class FunctionEval implements OperationEval {
 	/**
@@ -79,6 +78,7 @@ public abstract class FunctionEval implements OperationEval {
 
 		retval[0] = new Count();
 		retval[1] = new If();
+		retval[2] = new IsNa();
 
 		retval[3] = new IsError();
 		retval[ID.SUM] = AggregateFunction.SUM;

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

@@ -0,0 +1,56 @@
+/* ====================================================================
+   Licensed to the Apache Software Foundation (ASF) under one or more
+   contributor license agreements.  See the NOTICE file distributed with
+   this work for additional information regarding copyright ownership.
+   The ASF licenses this file to You under the Apache License, Version 2.0
+   (the "License"); you may not use this file except in compliance with
+   the License.  You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+==================================================================== */
+
+package org.apache.poi.hssf.record.formula.functions;
+
+import org.apache.poi.hssf.record.formula.eval.BoolEval;
+import org.apache.poi.hssf.record.formula.eval.ErrorEval;
+import org.apache.poi.hssf.record.formula.eval.Eval;
+import org.apache.poi.hssf.record.formula.eval.EvaluationException;
+import org.apache.poi.hssf.record.formula.eval.OperandResolver;
+import org.apache.poi.ss.usermodel.ErrorConstants;
+
+/**
+ * Implementation for Excel ISNA() function.<p/>
+ *
+ * <b>Syntax</b>:<br/>
+ * <b>ISNA</b>(<b>value</b>)<p/>
+ *
+ * <b>value</b>  The value to be tested<br/>
+ * <br/>
+ * Returns <tt>TRUE</tt> if the specified value is '#N/A', <tt>FALSE</tt> otherwise.
+ *
+ * @author Josh Micich
+ */
+public final class IsNa implements Function {
+
+	public Eval evaluate(Eval[] args, int srcCellRow, short srcCellCol) {
+		if(args.length != 1) {
+			return ErrorEval.VALUE_INVALID;
+		}
+		Eval arg = args[0];
+
+		try {
+			OperandResolver.getSingleValue(arg, srcCellRow, srcCellCol);
+		} catch (EvaluationException e) {
+			if (e.getErrorEval().getErrorCode() == ErrorConstants.ERROR_NA) {
+				return BoolEval.TRUE;
+			}
+		}
+		return BoolEval.FALSE;
+	}
+}