private boolean isTablePropertyModified(TableDescriptor oldDescriptor,
    TableDescriptor newDescriptor, String key) {
    String oldV = oldDescriptor.getValue(key);
    String newV = newDescriptor.getValue(key);
    if (oldV == null && newV == null) {
      return false;
    } else if (oldV != null && newV != null && oldV.equals(newV)) {
      return false;
    }
    return true;
  }
Comparing the value associated with a given key across two TableDescriptor instances'
properties.
@return True if the table property <code>key</code> is the same in both.
hbase-server/src/main/java/org/apache/hadoop/hbase/master/procedure/ModifyTableProcedure.java