Returns an array of Byte containing all of the elements of this collection. A generic unordered collection of elements that does not support duplicate elements. isNotEmpty (): Boolean. It returns a single element, or null if the collection has more than one element or it is empty. Returns a list of all elements sorted according to natural sort order of the value returned by specified selector function. A string will be empty if it is assigned “” or String.Empty (A constant for empty strings).. Syntax: public static bool IsNullOrEmpty(String str) to current accumulator value and each element with its index in the original collection. Check if Collection is Empty or Null in Java - Utility Methods. These functions return a number representing a statistical result after evaluating all elements. ... Returns the last element, or null if the collection is empty. Groups elements of the original collection by the key returned by the given keySelector function Returns a single list of all elements yielded from results of transform function being invoked on each element of original collection. Returns the single element, or throws an exception if the collection is empty or has more than one element. Returns true if element is found in the collection. And that’s the end of Part 2! Returns single element, or null if the collection is empty or has more than one element. Returns an array of UByte containing all of the elements of this collection. sliding along this collection with the given step, where each applied to each element in the collection or null if there are no elements. JVM. Returns true if the collection has no elements. Returns an array of Short containing all of the elements of this collection. Returns the first element matching the given predicate. Accumulates value starting with initial value and applying operation from left to right Returns the largest value according to the provided comparator Creates a string from all the elements separated using separator and using the given prefix and postfix if supplied. Returns a list containing the results of applying the given transform function Common. and appends the results to the given destination. Returns a list of all elements sorted descending according to natural sort order of the value returned by specified selector function. first list is built from the first values of each pair from this collection, Returns a list containing the results of applying the given transform function Appends all elements matching the given predicate to the given destination. In this short article, we will discuss how to check if the collection is empty or null in Java. More so than Java because it also has nullable types and can help prevent the dreaded NPE. You will notice the Kotlin examples do not specify the types. ... Kotlin - Null can not be a value of a non-null type String. using the specified random instance as the source of randomness. Returns an array of UInt containing all of the elements of this collection. Returns a list containing all elements not matching the given predicate. to each element, its index in the original collection and current accumulator value that starts with initial value. Returns a list containing only elements from the given collection Syntax of List.isEmpty() The syntax of List.isEmpty() function is. This is because Kotlin has full type inference and is completely type safe at compile time. It is used to check whether the specified string is null or an Empty string. New Project and fill all required details to create a … Methods in this interface support only read-only access to the list; Returns a random element from this collection using the specified source of randomness. Returns a list of pairs built from the elements of this collection and other collection with the same index. Returns a Map containing the values provided by valueTransform and indexed by keySelector functions applied to elements of the given collection. Accumulates value starting with the first element and applying operation from left to right The most common use of secondary constructor comes up when you need to extend a class that provides multiple constructors that initialize the class in different ways. Returns a Map containing the elements from the given collection indexed by the key In Kotlin ... or a `null` if the collection is empty. If the collection’s nullable, you can use isNullOrEmpty(). 1. isNullOrEmpty() function. By default, variables are non-null references and cannot be set to null. Returns first index of element, or -1 if the collection does not contain element. Returns a list containing successive accumulation values generated by applying operation from left to right applied to each element and puts to the destination map each group key associated with a list of corresponding elements. Accumulates value starting with initial value and applying operation from left to right second list is built from the second values of each pair from this collection. and appends only the non-null results to the given destination. Technically, isEmpty () sees it contains spaces and returns false. Convert this list of Kotlin strings to C array of C strings, allocating memory for the array and C strings with given AutofreeScope. Returns the smallest value according to the provided comparator Let's create a standard utility method to check if the collection is empty or null in Java. A map is actually an interface that has a pair interface inside, entries Set, keys Set and values Collection. 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