code: public ValueExpression getValueExpression(String name) {
  
          if (name == null) {
              throw new NullPointerException();
          }
  
          return ((bindings == null) ? null : bindings.get(name));
      }
docs: <p class="changed_added_2_0">Returns the {@link ValueExpression}
  used to calculate the value for the specified property name, if any.
  </p>
  
  @param name Name of the property for which to retrieve a
  {@link ValueExpression}
  
  @throws NullPointerException if <code>name</code>
  is <code>null</code>