1 files changed, 7 insertions, 0 deletions
diff --git a/libjava/java/nio/MappedByteBufferImpl.java b/libjava/java/nio/MappedByteBufferImpl.java
index 63e0225bc51..fdb64c5bb0f 100644
--- a/libjava/java/nio/MappedByteBufferImpl.java
+++ b/libjava/java/nio/MappedByteBufferImpl.java
@@ -117,6 +117,8 @@ final class MappedByteBufferImpl extends MappedByteBuffer
 
   public ByteBuffer compact()
   {
+    checkIfReadOnly();
+    mark = -1;
     int pos = position();
     if (pos > 0)
       {
@@ -126,6 +128,11 @@ final class MappedByteBufferImpl extends MappedByteBuffer
 	position(count);
 	limit(capacity());
       }
+    else
+      {
+	position(limit());
+	limit(capacity());
+      }
     return this;
   }