Null Safety

!! Not-null Assertion //use it when you are sure the value is notnull

//throws nullpointerexception if the value is found to be null

?.let{} safe call with let

?. Safe call operator

Val name: String = null

By default kotlin not support nullable.

If we want to assign null we can use -> Val name: String? = null

?.let{} safe call with let

//1. returns the length if the name is not null else return null

//2. Name?.let{//It Executes the block only if the name is notnull

Println("")

}

?: Elvis

// when we have a nullable reference name, we can say "is name is not null",use it ,

//otherwise use some non nullable value

3. Val nameLen=if(name!=null)

Name.length

Else

-1

Or

Val leng = name?.length?: -1