Java null

It's the only object reference we can write literally in code. Show 2 more comments. Community Bot 1 1 1 silver badge. Your example is generally better written as if "hi". If your object reference is null, then the call someObject. ColinD Agree just demonstrating here — jmj. It's always advisable to avoid nulls at all cost, so you don't need null checks at all ;. You can always use Objects. Objects This class consists of static utility methods for operating on objects.

Since: 1. Tigerware Tigerware 2, 2 2 gold badges 17 17 silver badges 33 33 bronze badges. Just to make it more visible for others see chin90's answer or the JavaDoc : Objects. Intellij always suggests to use Object. In Java 0 or null are simple types and not objects. The method equals is not built for simple types.

As stated by the JavaDoc it's always wise to read those : Consequently, if both arguments are null, true is returned. You get a NullPointerException. Nick Orton Nick Orton 3, 1 1 gold badge 20 20 silver badges 28 28 bronze badges. DixonD DixonD 6, 5 5 gold badges 29 29 silver badges 51 51 bronze badges.

It matters, since equals can only return false or cause a NullPointerException or something different if the overriden equals method is nonsense. When your obj will be null it will throw Null Point Exception. Erick G. Hagstrom 4, 1 1 gold badge 21 21 silver badges 38 38 bronze badges. The issue here is that field. This breaks usual Java behaviour and is therefore confusing.

It should only work for field. I don't know why the library developers thought, that this would be good to support. Btw, your first sentence has a grammar issue and it is unclear what you mean with it. Do you mean "Here is an example where str! I think that's because the jsonObject contains the "field" key that's why field isn't null, it has a reference which contains the json.

Yes, but I wouldn't treat Null like null and would use "null" instead. But I guess they did that to avoid requiring Strings. But even with that lib, field.

Well, the result can only be false or NullPointerException if equals is not overriden to something bad. So I never get confused and avoid problems with this solution: if str. Matheus Marques Matheus Marques 41 2 2 bronze badges.

If str is null this will be an NPE — typoerrpr. Additionally an empty string "" having length 0 is something entirely different than a null reference i. I have encountered this case last night. Kevin Orriss Kevin Orriss 3 3 gold badges 9 9 silver badges 23 23 bronze badges. Is it not completely redundant to add a 2nd check for null? JustinRowe It is not only redundant, it is also very wrong. Please, never do something like x. Tom, JustinRowe please see my answer above why this isn't redundant nor complete garbage stackoverflow.

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