Port more NIO changes over from trunk

git-svn-id: https://svn.apache.org/repos/asf/poi/branches/NIO_32_BRANCH@1055375 13f79535-47bb-0310-9956-ffa450edef68

3 files changed, 85 insertions, 18 deletions

diff --git a/src/java/org/apache/poi/hssf/usermodel/HSSFWorkbook.java b/src/java/org/apache/poi/hssf/usermodel/HSSFWorkbook.java
index 3a7ca03fc2..95a567bb5b 100644
--- a/src/java/org/apache/poi/hssf/usermodel/HSSFWorkbook.java
+++ b/src/java/org/apache/poi/hssf/usermodel/HSSFWorkbook.java
@@ -249,7 +249,25 @@ public class HSSFWorkbook extends POIDocument
     public HSSFWorkbook(DirectoryNode directory, POIFSFileSystem fs, boolean preserveNodes)
             throws IOException
     {
-        super(directory, fs);
+       this(directory, preserveNodes);
+    }
+    /**
+     * given a POI POIFSFileSystem object, and a specific directory
+     *  within it, read in its Workbook and populate the high and
+     *  low level models.  If you're reading in a workbook...start here.
+     *
+     * @param directory the POI filesystem directory to process from
+     * @param preserveNodes whether to preseve other nodes, such as
+     *        macros.  This takes more memory, so only say yes if you
+     *        need to. If set, will store all of the POIFSFileSystem
+     *        in memory
+     * @see org.apache.poi.poifs.filesystem.POIFSFileSystem
+     * @exception IOException if the stream cannot be read
+     */
+    public HSSFWorkbook(DirectoryNode directory, boolean preserveNodes)
+            throws IOException
+    {
+        super(directory);
         String workbookName = getWorkbookDirEntryName(directory);
 
         this.preserveNodes = preserveNodes;
diff --git a/src/java/org/apache/poi/poifs/filesystem/NPOIFSDocument.java b/src/java/org/apache/poi/poifs/filesystem/NPOIFSDocument.java
index 09536d4ade..3a2c286023 100644
--- a/src/java/org/apache/poi/poifs/filesystem/NPOIFSDocument.java
+++ b/src/java/org/apache/poi/poifs/filesystem/NPOIFSDocument.java
@@ -51,7 +51,7 @@ public final class NPOIFSDocument implements POIFSViewable {
       this._property = property;
       this._filesystem = filesystem;
 
-      if(property.getSize() <= POIFSConstants.BIG_BLOCK_MINIMUM_DOCUMENT_SIZE) {
+      if(property.getSize() < POIFSConstants.BIG_BLOCK_MINIMUM_DOCUMENT_SIZE) {
          _stream = new NPOIFSStream(_filesystem.getMiniStore(), property.getStartBlock());
          _block_size = _filesystem.getMiniStore().getBlockStoreBlockSize();
       } else {
diff --git a/src/java/org/apache/poi/poifs/filesystem/NPOIFSFileSystem.java b/src/java/org/apache/poi/poifs/filesystem/NPOIFSFileSystem.java
index e671d870bb..8a7b683315 100644
--- a/src/java/org/apache/poi/poifs/filesystem/NPOIFSFileSystem.java
+++ b/src/java/org/apache/poi/poifs/filesystem/NPOIFSFileSystem.java
@@ -107,7 +107,7 @@ public class NPOIFSFileSystem extends BlockStore
 
     /**
      * Creates a POIFSFileSystem from a <tt>File</tt>. This uses less memory than
-     *  creating from an <tt>InputStream</tt>.
+     *  creating from an <tt>InputStream</tt>. The File will be opened read-only
      *  
      * Note that with this constructor, you will need to call {@link #close()}
      *  when you're done to have the underlying file closed, as the file is
@@ -120,21 +120,70 @@ public class NPOIFSFileSystem extends BlockStore
     public NPOIFSFileSystem(File file)
          throws IOException
     {
+       this(file, true);
+    }
+    
+    /**
+     * Creates a POIFSFileSystem from a <tt>File</tt>. This uses less memory than
+     *  creating from an <tt>InputStream</tt>.
+     *  
+     * Note that with this constructor, you will need to call {@link #close()}
+     *  when you're done to have the underlying file closed, as the file is
+     *  kept open during normal operation to read the data out. 
+     *  
+     * @param file the File from which to read the data
+     *
+     * @exception IOException on errors reading, or on invalid data
+     */
+    public NPOIFSFileSystem(File file, boolean readOnly)
+         throws IOException
+    {
+       this(
+           (new RandomAccessFile(file, readOnly? "r" : "rw")).getChannel(),
+           true
+       );
+    }
+    
+    /**
+     * Creates a POIFSFileSystem from an open <tt>FileChannel</tt>. This uses 
+     *  less memory than creating from an <tt>InputStream</tt>.
+     *  
+     * Note that with this constructor, you will need to call {@link #close()}
+     *  when you're done to have the underlying Channel closed, as the channel is
+     *  kept open during normal operation to read the data out. 
+     *  
+     * @param channel the FileChannel from which to read the data
+     *
+     * @exception IOException on errors reading, or on invalid data
+     */
+    public NPOIFSFileSystem(FileChannel channel)
+         throws IOException
+    {
+       this(channel, false);
+    }
+    
+    private NPOIFSFileSystem(FileChannel channel, boolean closeChannelOnError)
+         throws IOException
+    {
        this();
-       
-       // Open the underlying channel
-       FileChannel channel = (new RandomAccessFile(file, "r")).getChannel();
-       
-       // Get the header
-       ByteBuffer headerBuffer = ByteBuffer.allocate(POIFSConstants.SMALLER_BIG_BLOCK_SIZE);
-       IOUtils.readFully(channel, headerBuffer);
-       
-       // Have the header processed
-       _header = new HeaderBlock(headerBuffer);
-       
-       // Now process the various entries
-       _data = new FileBackedDataSource(channel);
-       readCoreContents();
+
+       try {
+          // Get the header
+          ByteBuffer headerBuffer = ByteBuffer.allocate(POIFSConstants.SMALLER_BIG_BLOCK_SIZE);
+          IOUtils.readFully(channel, headerBuffer);
+          
+          // Have the header processed
+          _header = new HeaderBlock(headerBuffer);
+          
+          // Now process the various entries
+          _data = new FileBackedDataSource(channel);
+          readCoreContents();
+       } catch(IOException e) {
+          if(closeChannelOnError) {
+             channel.close();
+          }
+          throw e;
+       }
     }
     
     /**
@@ -435,7 +484,7 @@ public class NPOIFSFileSystem extends BlockStore
              // Oh joy, we need a new XBAT too...
              xbat = createBAT(offset+1, false);
              xbat.setValueAt(0, offset);
-             bat.setValueAt(offset+1, POIFSConstants.DIFAT_SECTOR_BLOCK);
+             bat.setValueAt(1, POIFSConstants.DIFAT_SECTOR_BLOCK);
              
              // Will go one place higher as XBAT added in
              offset++;