Empty byte array case for HexDump

git-svn-id: https://svn.apache.org/repos/asf/jakarta/poi/trunk@353579 13f79535-47bb-0310-9956-ffa450edef68

src/java/org/apache/poi/util/HexDump.java

@@ -73,6 +73,12 @@ public class HexDump
             throws IOException, ArrayIndexOutOfBoundsException,
                     IllegalArgumentException
     {
+        if (data.length == 0)
+        {
+            stream.write( "No Data".getBytes() );
+            stream.flush();
+            return;
+        }
         if ((index < 0) || (index >= data.length))
         {
             throw new ArrayIndexOutOfBoundsException(
@@ -83,6 +89,7 @@ public class HexDump
         {
             throw new IllegalArgumentException("cannot write to nullstream");
         }
+
         long         display_offset = offset + index;
         StringBuffer buffer         = new StringBuffer(74);
 

src/testcases/org/apache/poi/util/TestHexDump.java

@@ -277,6 +277,11 @@ public class TestHexDump
 
             // as expected
         }
+
+        // verify proper behaviour with empty byte array
+        ByteArrayOutputStream os = new ByteArrayOutputStream( );
+        HexDump.dump( new byte[0], 0, os, 0 );
+        assertEquals( "No Data", os.toString() );
     }
 
     public void testToHex()