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We have set the property of the variable as String type with the null safety operator, which will check the nullability of the variable. In the above code main function, we have declared a variable as “var” and assigned it the name “myStr”.

The right-hand side is considered when we have the left-hand side expression null. When there is a need to return a default value in the case of a NULL reference, we have to use the Elvis operator. Otherwise, we have an “else” block to execute.Īs we have a string stored in a variable “str”, the condition becomes true, and the output of the string length is displayed on the screen below.Įxample # 2: Using Elvis operator for checking null in Kotlin: The “if” block will execute and print the length of the string if the condition is true. Then, we have an “if” statement in which we have kept the variable “str” not equal to a null value. The “str” contains the string value, which we have printed through the kotlin println function. The variable is assigned a name “str” and sets the String type property to it. In the above code, we have the main function. Let’s have the code implementation below. The “if-else” clause is used in the code to validate a variable’s null safety. To check conditions, we use the “if” keyword. To understand the basics of using the technique to check null values in kotlin, we have the following examples: Example # 1: Using if-else for checking null in Kotlin: Otherwise, Kotlin will notify that the variable has null references, generating a compilation error. However, in the occurrence of nullable variables, we must explicitly handle the null condition. On a non-nullable variable, we can invoke a function or access a property. As a result, we can’t give a variable a null value because it will trigger a compilation error. Kotlin’s variables are all non-nullable by default. The goal of Kotlin is to eliminate the possibility of a NullPointerException. In the article, we will discuss the preferred and sophisticated technique to effectively manage null safety in Kotlin to use a few specialized operators. A NullPointerException is thrown by the Kotlin compiler if it finds a null reference before executing any additional statements. If you have ever written code in Java or another language with the concept of null references, you have probably run across a NullPointerException.