fixed XSSFWorkbook.createSheet to properly increment sheetId when sheetId sequence is not continious

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@768389 13f79535-47bb-0310-9956-ffa450edef68

src/documentation/content/xdocs/changes.xml

@@ -37,6 +37,7 @@
 
 		<!-- Don't forget to update status.xml too! -->
         <release version="3.5-beta6" date="2009-??-??">
+           <action dev="POI-DEVELOPERS" type="fix">47089 - Fixed XSSFWorkbook.createSheet to properly increment sheetId</action>
            <action dev="POI-DEVELOPERS" type="fix">46568 - Fixed XSLFPowerPointExtractor to properly process line breaks</action>
            <action dev="POI-DEVELOPERS" type="fix">39056 - Fixed POIFSFileSystem to set CLSID of root when constructing instances from InputStream</action>
            <action dev="POI-DEVELOPERS" type="fix">47054 - Fixed cloneStyleFrom to avoid exception when cloning styles of the same family</action>

src/documentation/content/xdocs/status.xml

@@ -34,6 +34,7 @@
 	<!-- Don't forget to update changes.xml too! -->
     <changes>
         <release version="3.5-beta6" date="2009-??-??">
+           <action dev="POI-DEVELOPERS" type="fix">47089 - Fixed XSSFWorkbook.createSheet to properly increment sheetId</action>
            <action dev="POI-DEVELOPERS" type="fix">46568 - Fixed XSLFPowerPointExtractor to properly process line breaks</action>
            <action dev="POI-DEVELOPERS" type="fix">39056 - Fixed POIFSFileSystem to set CLSID of root when constructing instances from InputStream</action>
            <action dev="POI-DEVELOPERS" type="fix">47054 - Fixed cloneStyleFrom to avoid exception when cloning styles of the same family</action>

src/ooxml/java/org/apache/poi/xssf/usermodel/XSSFWorkbook.java

@@ -453,7 +453,9 @@ public class XSSFWorkbook extends POIXMLDocument implements Workbook, Iterable<X
 
         CTSheet sheet = addSheet(sheetname);
 
-        int sheetNumber = getNumberOfSheets() + 1;
+        int sheetNumber = 1;
+        for(XSSFSheet sh : sheets) sheetNumber = (int)Math.max(sh.sheet.getSheetId() + 1, sheetNumber);
+
         XSSFSheet wrapper = (XSSFSheet)createRelationship(XSSFRelation.WORKSHEET, XSSFFactory.getInstance(), sheetNumber);
         wrapper.sheet = sheet;
         sheet.setId(wrapper.getPackageRelationship().getId());

src/ooxml/testcases/org/apache/poi/xssf/usermodel/TestXSSFWorkbook.java

@@ -227,5 +227,18 @@ public final class TestXSSFWorkbook extends BaseTestWorkbook {
 		assertEquals(2, st.getFills().size());
 		assertEquals(1, st.getBorders().size());
 	}
-	
+
+    public void testIncrementSheetId() throws Exception {
+        XSSFWorkbook wb = getTestDataProvider().createWorkbook();
+        int sheetId = (int)wb.createSheet().sheet.getSheetId();
+        assertEquals(1, sheetId);
+        sheetId = (int)wb.createSheet().sheet.getSheetId();
+        assertEquals(2, sheetId);
+
+        //test file with gaps in the sheetId sequence
+        wb = getTestDataProvider().openSampleWorkbook("47089.xlsm");
+        int lastSheetId = (int)wb.getSheetAt(wb.getNumberOfSheets() - 1).sheet.getSheetId();
+        sheetId = (int)wb.createSheet().sheet.getSheetId();
+        assertEquals(lastSheetId+1, sheetId);
+    }
 }