FuncPtg stores 2 bytes of data where AbstractFuncPtg says it is 4 bytes long. Store the other 2 bytes when reading an excel file so that the "Warning: Data may have been lost" prompt is avoided after serialization.

git-svn-id: https://svn.apache.org/repos/asf/jakarta/poi/trunk@353043 13f79535-47bb-0310-9956-ffa450edef68

src/java/org/apache/poi/hssf/record/formula/FuncPtg.java

@@ -4,14 +4,23 @@ import org.apache.poi.util.LittleEndian;
 /**
  *
  * @author Jason Height (jheight at chariot dot net dot au)
+ * @author Danny Mui (dmui at apache dot org) (Leftover handling)
  */
 public class FuncPtg extends AbstractFunctionPtg{
     
     public final static byte sid  = 0x21;
     private int numParams=0;
+    
+    /**
+     * FuncPtgs are defined to be 4 bytes but the actual FuncPtg uses only 2 bytes.
+     * If we have leftOvers that are read from the file we should serialize them back out.
+     * <p>
+     * If the leftovers are removed, a prompt "Warning: Data may have been lost occurs in Excel"
+     */
+	protected byte[] leftOvers = null;
 
     private FuncPtg() {
-      //Required for clone methods
+      //Required for clone methods      
     }
 
     /**Creates new function pointer from a byte array 
@@ -21,17 +30,28 @@ public class FuncPtg extends AbstractFunctionPtg{
         offset++;
         //field_1_num_args = data[ offset + 0 ];
         field_2_fnc_index  = LittleEndian.getShort(data,offset + 0 );
+        
+        
+        if (data.length - offset > 2) { //save left overs if there are any
+			leftOvers = new byte[2];
+        	System.arraycopy(data, offset+1, leftOvers, 0, leftOvers.length);
+        }
+        	
         try {
             numParams = ( (Integer)functionData[field_2_fnc_index][2]).intValue();
         } catch (NullPointerException npe) {
             numParams=0;
         }   
+        
     }
     
      public void writeBytes(byte[] array, int offset) {
         array[offset+0]= (byte) (sid + ptgClass);
         //array[offset+1]=field_1_num_args;
         LittleEndian.putShort(array,offset+1,field_2_fnc_index);
+        if (leftOvers != null) {
+        	System.arraycopy(leftOvers, 0, array, offset+2, leftOvers.length);
+        }
     }
     
      public int getNumberOfOperands() {

src/testcases/org/apache/poi/hssf/HSSFTests.java

@@ -50,6 +50,7 @@ import org.apache.poi.hssf.record.TestTickRecord;
 import org.apache.poi.hssf.record.TestUnitsRecord;
 import org.apache.poi.hssf.record.TestValueRangeRecord;
 import org.apache.poi.hssf.record.aggregates.TestRowRecordsAggregate;
+import org.apache.poi.hssf.record.formula.TestFuncPtg;
 import org.apache.poi.hssf.usermodel.TestCellStyle;
 import org.apache.poi.hssf.usermodel.TestFormulas;
 import org.apache.poi.hssf.usermodel.TestHSSFCell;
@@ -149,6 +150,9 @@ public class HSSFTests
         suite.addTest(new TestSuite(TestRKUtil.class));
         suite.addTest(new TestSuite(TestSheetReferences.class));
         
+        //not a real junit guru so i'm just adding it here
+        suite.addTest(new TestSuite(TestFuncPtg.class));
+        
         //$JUnit-END$
         return suite;
     }

src/testcases/org/apache/poi/hssf/record/formula/TestFuncPtg.java

@@ -0,0 +1,101 @@
+/* ====================================================================
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2003 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution,
+ *    if any, must include the following acknowledgment:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowledgment may appear in the software itself,
+ *    if and wherever such third-party acknowledgments normally appear.
+ *
+ * 4. The names "Apache" and "Apache Software Foundation" and
+ *    "Apache POI" must not be used to endorse or promote products
+ *    derived from this software without prior written permission. For
+ *    written permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache",
+ *    "Apache POI", nor may "Apache" appear in their name, without
+ *    prior written permission of the Apache Software Foundation.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.poi.hssf.record.formula;
+
+import junit.framework.TestCase;
+
+
+
+/**
+ * Make sure the FuncPtg performs as expected
+ * @author Danny Mui (dmui at apache dot org)
+ */
+public class TestFuncPtg extends TestCase {
+
+	public TestFuncPtg(String name) {
+		super(name);
+		
+	}
+
+	public static void main(java.lang.String[] args) {        
+        
+		junit.textui.TestRunner.run(TestFuncPtg.class);
+	}
+
+
+	/**
+	 * Make sure the left overs are re-serialized on excel file reads to avoid
+	 * the "Warning: Data may have been lost" prompt in excel.
+	 * <p>
+	 * This ptg represents a LEN function extracted from excel
+	 */
+	public void testLeftOvers() {
+		byte[] fakeData = new byte[4];
+		
+		fakeData[0] = (byte)0x41;  
+		fakeData[1] = (byte)0x20;  //function index
+		fakeData[2] = (byte)0;     //leftovers begin
+		fakeData[3] = (byte)8;
+		
+		FuncPtg ptg = new FuncPtg(fakeData, 0);
+		
+		assertEquals("Len formula index is not 32(20H)",(int)0x20, ptg.getFunctionIndex());
+		assertEquals("Number of operands in the len formula",1, ptg.getNumberOfOperands());
+		assertEquals("first leftover byte is not 0", (byte)0, ptg.leftOvers[0]);
+		assertEquals("second leftover byte is not 8", (byte)8, ptg.leftOvers[1]);
+		
+	}
+
+}