### Eclipse Workspace Patch 1.0
#P ApachePOI
Index: src/ooxml/java/org/apache/poi/xssf/usermodel/XSSFWorkbook.java
===================================================================
--- src/ooxml/java/org/apache/poi/xssf/usermodel/XSSFWorkbook.java	(revision 1726153)
+++ src/ooxml/java/org/apache/poi/xssf/usermodel/XSSFWorkbook.java	(working copy)
@@ -540,13 +540,30 @@
      */
     @Override
     public XSSFSheet cloneSheet(int sheetNum) {
+        return cloneSheet(sheetNum, null);
+    }
+    /**
+     * Create an XSSFSheet from an existing sheet in the XSSFWorkbook.
+     *  The cloned sheet is a deep copy of the original but with a new given
+     *  name.
+     *
+     * @return XSSFSheet representing the cloned sheet.
+     * @throws IllegalArgumentException if the sheet index or the sheet
+     *         name is invalid
+     * @throws POIXMLException if there were errors when cloning
+     */
+    public XSSFSheet cloneSheet(int sheetNum, String newName) {
         validateSheetIndex(sheetNum);
-
         XSSFSheet srcSheet = sheets.get(sheetNum);
-        String srcName = srcSheet.getSheetName();
-        String clonedName = getUniqueSheetName(srcName);
 
-        XSSFSheet clonedSheet = createSheet(clonedName);
+        if (newName == null) {
+            String srcName = srcSheet.getSheetName();
+            newName = getUniqueSheetName(srcName);
+        } else {
+            validateSheetName(newName);
+        }
+
+        XSSFSheet clonedSheet = createSheet(newName);
         try {
             ByteArrayOutputStream out = new ByteArrayOutputStream();
             srcSheet.write(out);
@@ -763,8 +780,7 @@
             throw new IllegalArgumentException("sheetName must not be null");
         }
 
-        if (containsSheet( sheetname, sheets.size() ))
-               throw new IllegalArgumentException( "The workbook already contains a sheet of this name");
+        validateSheetName(sheetname);
 
         // YK: Mimic Excel and silently truncate sheet names longer than 31 characters
         if(sheetname.length() > 31) sheetname = sheetname.substring(0, 31);
@@ -804,6 +820,13 @@
         return wrapper;
     }
 
+    private void validateSheetName(
+            final String sheetname) throws IllegalArgumentException {
+        if (containsSheet( sheetname, sheets.size() )) {
+            throw new IllegalArgumentException("The workbook already contains a sheet of this name");
+        }
+    }
+
     protected XSSFDialogsheet createDialogsheet(String sheetname, CTDialogsheet dialogsheet) {
         XSSFSheet sheet = createSheet(sheetname);
         return new XSSFDialogsheet(sheet);
Index: src/ooxml/testcases/org/apache/poi/xssf/AllXSSFTests.java
===================================================================
--- src/ooxml/testcases/org/apache/poi/xssf/AllXSSFTests.java	(revision 1726153)
+++ src/ooxml/testcases/org/apache/poi/xssf/AllXSSFTests.java	(working copy)
@@ -47,7 +47,8 @@
     TestCellReference.class,
     TestCTColComparator.class,
     TestNumericRanges.class,       
-    TestCellFormatPart.class
+    TestCellFormatPart.class,
+    TestXSSFCloneSheet.class
 })
 public final class AllXSSFTests {
 }
Index: src/ooxml/testcases/org/apache/poi/xssf/TestXSSFCloneSheet.java
===================================================================
--- src/ooxml/testcases/org/apache/poi/xssf/TestXSSFCloneSheet.java	(revision 0)
+++ src/ooxml/testcases/org/apache/poi/xssf/TestXSSFCloneSheet.java	(working copy)
@@ -0,0 +1,65 @@
+package org.apache.poi.xssf;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.fail;
+
+import org.apache.poi.xssf.usermodel.XSSFSheet;
+import org.apache.poi.xssf.usermodel.XSSFWorkbook;
+import org.junit.Before;
+import org.junit.Test;
+
+public class TestXSSFCloneSheet {
+
+    private static final String OTHER_SHEET_NAME = "Another";
+    private static final String VALID_SHEET_NAME = "Sheet01";
+    private XSSFWorkbook wb;
+
+    @Before
+    public void setUp() {
+        wb = new XSSFWorkbook();
+        wb.createSheet(VALID_SHEET_NAME);  
+    }
+    
+    
+    @Test
+    public void testCloneSheetIntValid() {
+        wb.cloneSheet(0);
+        assertEquals(2, wb.getNumberOfSheets());
+        try {
+            wb.cloneSheet(2);
+            fail("ShouldFail");
+        } catch (IllegalArgumentException e) {
+            
+        }
+    }
+
+    @Test
+    public void testCloneSheetIntInvalid() {
+        try {
+            wb.cloneSheet(1);
+            fail("Should Fail");
+        } catch (IllegalArgumentException e) {
+            
+        }
+        assertEquals(1, wb.getNumberOfSheets());
+    }
+
+    @Test
+    public void testCloneSheetIntStringValidName() {
+        XSSFSheet cloned = wb.cloneSheet(0, OTHER_SHEET_NAME);
+        assertEquals(OTHER_SHEET_NAME, cloned.getSheetName());
+        assertEquals(2, wb.getNumberOfSheets());
+    }
+    
+    @Test
+    public void testCloneSheetIntStringInvalidName() {
+        try {
+            wb.cloneSheet(0, VALID_SHEET_NAME);
+            fail("Should fail");
+        } catch (IllegalArgumentException e) {
+            
+        }
+        assertEquals(1, wb.getNumberOfSheets());
+    }
+
+}