8266320: (bf) ReadOnlyBufferException in heap buffer put(String,int,int) should not be conditional

Reviewed-by: alanb, bpb

Author: marschall

src/java.base/share/classes/java/nio/Heap-X-Buffer.java.template

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000, 2020, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2000, 2021, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -272,11 +272,10 @@ class Heap$Type$Buffer$RW$
 #if[char]
 
     public $Type$Buffer put(String src, int start, int end) {
+#if[rw]
         checkScope();
         int length = end - start;
         Objects.checkFromIndexSize(start, length, src.length());
-        if (isReadOnly())
-            throw new ReadOnlyBufferException();
         int pos = position();
         int lim = limit();
         int rem = (pos <= lim) ? lim - pos : 0;
@@ -285,6 +284,9 @@ class Heap$Type$Buffer$RW$
         src.getChars(start, end, hb, ix(pos));
         position(pos + length);
         return this;
+#else[rw]
+        throw new ReadOnlyBufferException();
+#end[rw]
     }
 
 #end[char]