Fix first part of bug #51514 - HSSF copy nodes from NPOIFS

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@1147179 13f79535-47bb-0310-9956-ffa450edef68

src/documentation/content/xdocs/status.xml

@@ -34,6 +34,7 @@
 
     <changes>
         <release version="3.8-beta4" date="2011-??-??">
+           <action dev="poi-developers" type="fix">51514 - avoid NPE when copying nodes from one HSSF workbook to a new one, when opened from NPOIFS</action>
            <action dev="poi-developers" type="fix">51504 - avoid NPE when DefaultRowHeight or DefaultColumnWidth records are missing</action>
            <action dev="poi-developers" type="fix">51502 - Correct Subtotal function javadoc entry</action>
            <action dev="poi-developers" type="add">Support for hyperlinks in SXSSF</action>

src/java/org/apache/poi/POIDocument.java

@@ -239,19 +239,26 @@ public abstract class POIDocument {
 	protected void copyNodes(POIFSFileSystem source, POIFSFileSystem target,
 	                          List<String> excepts) throws IOException {
 		//System.err.println("CopyNodes called");
-
+	   copyNodes(source.getRoot(), target.getRoot(), excepts);
-		DirectoryEntry root = source.getRoot();
-		DirectoryEntry newRoot = target.getRoot();
-
-		Iterator<Entry> entries = root.getEntries();
-		while (entries.hasNext()) {
-			Entry entry = entries.next();
-			if (!excepts.contains(entry.getName())) {
-				copyNodeRecursively(entry,newRoot);
-			}
-		}
 	}
 		
+   /**
+    * Copies nodes from one POIFS to the other minus the excepts
+    * @param source is the source POIFS to copy from
+    * @param target is the target POIFS to copy to
+    * @param excepts is a list of Strings specifying what nodes NOT to copy
+    */
+   protected void copyNodes(DirectoryNode sourceRoot, DirectoryNode targetRoot,
+                             List<String> excepts) throws IOException {
+      Iterator<Entry> entries = sourceRoot.getEntries();
+      while (entries.hasNext()) {
+         Entry entry = entries.next();
+         if (!excepts.contains(entry.getName())) {
+            copyNodeRecursively(entry,targetRoot);
+         }
+      }
+   }
+      
 	/**
 	 * Copies an Entry into a target POIFS directory, recursively
 	 */

src/java/org/apache/poi/hssf/usermodel/HSSFWorkbook.java

@@ -36,27 +36,27 @@ import org.apache.poi.ddf.EscherBlipRecord;
 import org.apache.poi.ddf.EscherRecord;
 import org.apache.poi.hssf.OldExcelFormatException;
 import org.apache.poi.hssf.model.HSSFFormulaParser;
-import org.apache.poi.hssf.model.RecordStream;
 import org.apache.poi.hssf.model.InternalSheet;
 import org.apache.poi.hssf.model.InternalWorkbook;
+import org.apache.poi.hssf.model.RecordStream;
 import org.apache.poi.hssf.record.*;
 import org.apache.poi.hssf.record.aggregates.RecordAggregate.RecordVisitor;
 import org.apache.poi.hssf.record.common.UnicodeString;
+import org.apache.poi.hssf.util.CellReference;
+import org.apache.poi.poifs.filesystem.DirectoryNode;
+import org.apache.poi.poifs.filesystem.POIFSFileSystem;
 import org.apache.poi.ss.formula.FormulaShifter;
+import org.apache.poi.ss.formula.FormulaType;
+import org.apache.poi.ss.formula.SheetNameFormatter;
 import org.apache.poi.ss.formula.ptg.Area3DPtg;
 import org.apache.poi.ss.formula.ptg.MemFuncPtg;
 import org.apache.poi.ss.formula.ptg.OperandPtg;
 import org.apache.poi.ss.formula.ptg.Ptg;
 import org.apache.poi.ss.formula.ptg.Ref3DPtg;
-import org.apache.poi.ss.formula.SheetNameFormatter;
 import org.apache.poi.ss.formula.ptg.UnionPtg;
-import org.apache.poi.hssf.util.CellReference;
-import org.apache.poi.poifs.filesystem.DirectoryNode;
-import org.apache.poi.poifs.filesystem.POIFSFileSystem;
 import org.apache.poi.ss.formula.udf.AggregatingUDFFinder;
 import org.apache.poi.ss.formula.udf.UDFFinder;
 import org.apache.poi.ss.usermodel.Row.MissingCellPolicy;
-import org.apache.poi.ss.formula.FormulaType;
 import org.apache.poi.ss.util.WorkbookUtil;
 import org.apache.poi.util.POILogFactory;
 import org.apache.poi.util.POILogger;
@@ -1244,13 +1244,12 @@ public final class HSSFWorkbook extends POIDocument implements org.apache.poi.ss
             //  out correctly shortly, so don't include the old one
             excepts.add("WORKBOOK");
 
-            POIFSFileSystem srcFs = this.directory.getFileSystem();
             // Copy over all the other nodes to our new poifs
-            copyNodes(srcFs, fs, excepts);
+            copyNodes(this.directory, fs.getRoot(), excepts);
 
             // YK: preserve StorageClsid, it is important for embedded workbooks,
             // see Bugzilla 47920
-            fs.getRoot().setStorageClsid(srcFs.getRoot().getStorageClsid());
+            fs.getRoot().setStorageClsid(this.directory.getStorageClsid());
         }
         fs.writeFilesystem(stream);
     }