Java, null list [closed]

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How can I verify if a List is null in Java ?

thanks

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By if condition:

if (list == null){
  // do something
}

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List myList = getListFromSomeMethodThatMightReturnNullAlthoughItsBetterToReturnAnEmptyListThenYouWouldntHaveToDoAnyStupidNullChecking();

if (myList == null){

}

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A List instance can't be null, an instance is always something. A List type variable can be null and to test this, use the expression

 List<?> list = null;
 if (list == null) {System.out.println("I'm null");}

A List instance can by empty, meaning the list doesn't contain any values. To ways to test this:

 if (list.size() == 0) {...}     
 if (list.isEmpty()) {...}

A List instance can contain items that represent null. To find those, iterate through the list:

 for(Object o:list)
   if (o == null) {...}

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If you have a variable myList of type List, you can do this by:

if(myList == null)
{
}