Helper method to report the number of blocks used in a BAT

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@1689504 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 15 insertions, 2 deletions

diff --git a/src/java/org/apache/poi/poifs/storage/BATBlock.java b/src/java/org/apache/poi/poifs/storage/BATBlock.java
index 8712e65f6f..53099644ac 100644
--- a/src/java/org/apache/poi/poifs/storage/BATBlock.java
+++ b/src/java/org/apache/poi/poifs/storage/BATBlock.java
@@ -30,8 +30,6 @@ import org.apache.poi.util.LittleEndian;
 /**
  * A block of block allocation table entries. BATBlocks are created
  * only through a static factory method: createBATBlocks.
- *
- * @author Marc Johnson (mjohnson at apache dot org)
  */
 public final class BATBlock extends BigBlock {
     /**
@@ -301,6 +299,21 @@ public final class BATBlock extends BigBlock {
     public boolean hasFreeSectors() {
        return _has_free_sectors;
     }
+    /**
+     * How many sectors in this block are taken?
+     * Note that calling {@link #hasFreeSectors()} is much quicker
+     */
+    public int getUsedSectors(boolean isAnXBAT) {
+        int usedSectors = 0;
+        int toCheck = _values.length;
+        if (isAnXBAT) toCheck--; // Last is a chain location
+        for(int k=0; k<toCheck; k++) {
+            if(_values[k] != POIFSConstants.UNUSED_BLOCK) {
+                usedSectors ++;
+            }
+        }
+        return usedSectors;
+    }
     
     public int getValueAt(int relativeOffset) {
        if(relativeOffset >= _values.length) {