Windows Test Case:
-----------------
I used removeNode() in Threads case 1:
         throws IllegalStateException as expected.
 
 I used removeNode() in Two JVM case 2:
      throws java.lang.InternalError
  with messages.


 ---------------------case1 thread -------------------------
 N1 node is created Thread01
 N1.put("k","newvalue");
 is called repeatedly
 
 N1 node is created in Thread02
N1.removeNode() is called
 .
 In Thread01 IllegalStateException is thrown as per the document.

 --------------------------------------case 2 two jvm -------------
 In Test01.java
    N1.node is created
   N1.put("k","newvalue");
    is called repeatedly.
In Test02.java
    N1.node is created
    N1.removeNode() is called.

One window java Test01 started
 in Second window java Tst02 started

In Test01 program java.lang.InternalError:
                        with message is thrown.