Method Detail

• public boolean asBoolean()

  A null object always coerces to false.

  Returns:

  false

• public Object asType(Class c)

  Type conversion method for null.

  Parameters:

  c - - the class to convert to

  Returns:

  always null

• public Object clone()

  Since this is implemented as a singleton, we should avoid the use of the clone method

• public boolean equals(Object to)

  null is only equal to null

  Parameters:

  to - - the reference object with which to compare

  Returns:

  - true if this object is the same as the to argument

• public static NullObject getNullObject()

  get the NullObject reference

  Returns:

  the null object

• public Object getProperty(String property)

  Tries to get a property on null, which will always fail

  Parameters:

  property - - the property to get

  Returns:

  a NPE

• public int hashCode()

• public Object invokeMethod(String name, Object args)

  Tries to invoke a method on null, which will always fail

  Parameters:

  name - the name of the method to invoke

  args - - arguments to the method

  Returns:

  a NPE

• public boolean is(Object other)

  The method "is" is used to test for equal references. This method will return true only if the given parameter is null

  Parameters:

  other - - the object to test

  Returns:

  true if other is null

• public Iterator iterator()

  iterator() method to be able to iterate on null. Note: this part is from Invoker

  Returns:

  an iterator for an empty list

• public Object plus(String s)

  Allows to add a String to null. The result is concatenated String of the result of calling toString() on this object and the String in the parameter.

  Parameters:

  s - - the String to concatenate

  Returns:

  the concatenated string

• public Object plus(Object o)

  Fallback for null+null. The result is always a NPE. The plus(String) version will catch the case of adding a non null String to null.

  Parameters:

  o - - the Object

  Returns:

  nothing

• public void setProperty(String property, Object newValue)

  Tries to set a property on null, which will always fail

  Parameters:

  property - - the proprty to set

  newValue - - the new value of the property

• public String toString()

• <T> public T with(Closure<T> closure)

  Allows the closure to be called for NullObject

  Parameters:

  closure - the closure to call on the object

  Returns:

  result of calling the closure