core: FileTracker: Use stateid4.getType instead of byteAt

With the introduction of stateid4.getType, let's not make any further
assumptions about how the type is stored in the Opaque.

Add a static getType variant in stateid4 and call that instead of
Opaque.byteAt.

Signed-off-by: Christian Kohlschütter <[email protected]>

Author: kohlschuetter

core/src/main/java/org/dcache/nfs/v4/FileTracker.java

@@ -475,7 +475,7 @@ public int getShareAccess(NFS4Client client, Inode inode, Opaque stateid)
         lock.lock();
         try {
 
-            switch (stateid.byteAt(11)) {
+            switch (stateid4.getType(stateid)) {
                 case Stateids.LOCK_STATE_ID:
                     NFS4State lockState = client.state(stateid);
                     stateid = lockState.getOpenState().stateid().getOpaque();

core/src/main/java/org/dcache/nfs/v4/xdr/stateid4.java

@@ -78,6 +78,10 @@ public int getType() {
         return opaque.byteAt(11);
     }
 
+    public static int getType(Opaque stateIdOther) {
+        return stateIdOther.byteAt(11);
+    }
+
     @Override
     public stateid4 clone() {
         return new stateid4(seqid, opaque);