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I don't fully understand the last line in following piece of code

 Field init = ReflectionUtils.findField(ABCClass.class, "init");
 ReflectionUtils.makeAccessible(init);
 init.set(null, false);
What i do understand that its setting the AbcClass.init=false using Reflection API. What i dont understand is why we dont have a setter like 
set(Object value) // looks logical as we have reference to field , we can simply set the value
but instead we have Something like
set(Object obj,Object value) 
I went through the api doc http://docs.oracle.com/javase/6/docs/api/java/lang/reflect/Field.html#set(java.lang.Object, java.lang.Object)
it says 
  
If the underlying field is static, the obj argument is ignored; it may
  be null. 
  
Otherwise the underlying field is an instance field. If the specified
  object argument is null, the method throws a NullPointerException.
But in my test case its not throwing any null pointer exception
I tried googling around for more example usage of this api , didnt find any useful example , may be some more examples can help me understand better.
The reason I can imagine is this.
The way you are getting that field it doesn't know the instance it belongs to. In static fields that is fine since static makes the field belong to the class and can exist independently without an instantiated object.
But a non static field will need an instantiated object to exist. Resulting in the set method requiring to know what that instance is.
        
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