TinyTM source bugs

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peeyush Agrawal

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May 5, 2012, 5:57:33 PM5/5/12

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Hi,
http://www.elsevierdirect.com/companions/9780123705914/exercises/14~Chapter_18.zip
Above link contains the source code of chapter-18, which has implementation of obstruction-free linked list and skip-list ( also locking linked-list and skip-list ).
But when I run ofree linked-list/skip-list cases, It gives run-time error :
Exceptions are:
TinyTM.exceptions.PanicException: java.lang.NullPointerException
        at TinyTM.TThread.doIt(TThread.java:51)
        at TinyTM.list.ofree.ListTest$TestThread.run(ListTest.java:117)
Caused by: java.lang.NullPointerException
        at TinyTM.list.ofree.TNode.getNext(TNode.java:54)
        at TinyTM.list.ofree.List.add(List.java:40)
        at TinyTM.list.ofree.ListTest$TestThread$1.call(ListTest.java:119)
        at TinyTM.list.ofree.ListTest$TestThread$1.call(ListTest.java:117)
        at TinyTM.TThread.doIt(TThread.java:41)
        ... 1 more

Upon investigating the issue, turns out that from FreeObject.java, openRead function is returning null. which is

   if (start.compareAndSet(oldLocator, newLocator)) {
            return newLocator.newVersion; // this value is null.
          }
If someone has right direction, what to do, kindly let me know. also update on the companion website.

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