A stream is a sequence of objects that supports various methods which can be pipelined to produce the desired result. noneMatch() of Stream class returns whether no elements of this stream match the provided predicate. It may not evaluate the predicate on all elements if not necessary for determining the result. This is a short-circuiting terminal operation. A terminal operation is short-circuiting if, when presented with infinite input, it may terminate in finite time.
Tip: It works. opposite to Stream anymatch() method.
Syntax:
boolean noneMatch(Predicate<? super T> predicate)
Where, T is the type of the input to the predicate and the function returns true if either no elements of the stream match the provided predicate or the stream is empty, otherwise false.
Note : If the stream is empty then true is returned and the predicate is not evaluated.
Now we will be discussing out few examples where we will be covering different scenarios while implementing Stream noneMatch() method via clean java programs as follows:
- To check that there is no string of a specific custom length
- To check that there is no element less than 0
- To check that there is no element with required characters at required position
Example 1: To check that there is no string of length 4.
Java
// Java Program to Illustrate noneMatch() method// of Stream class to check whether// no elements of this stream match the// provided predicate (Predicate predicate) // Importing Stream class from java.util.stream sub packageimport java.util.stream.Stream; // Main classclass GFG { // Main driver method public static void main(String[] args) { // Creating a Stream of strings // Custom input strings are passed as arguments Stream<String> stream = Stream.of("CSE", "C++", "Java", "DS"); // Now using Stream noneMatch(Predicate predicate) // and later storing the boolean answer as boolean answer = stream.noneMatch(str -> (str.length() == 4)); // Printing the boolean value on the console System.out.println(answer); }} |
false
Example 2 : To check that there is no element less than 0.
Java
// Java Program to Illustrate noneMatch() method// of Stream class to check whether no elements// of this stream match the provided predicate // Importing required utility classesimport java.util.*; // Main classclass GFG { // amin driver method public static void main(String[] args) { // Creating a list of Integers using asList() of // Arrays class by declaring object of List List<Integer> list = Arrays.asList(4, 0, 6, 2); // Using Stream noneMatch(Predicate predicate) and // storing the boolean value boolean answer = list.stream().noneMatch(num -> num < 0); // Printing and displaying the above boolean value System.out.println(answer); }} |
true
Example 3 : To check that there is no element with required characters at required position.
Java
// Java Program to Illustrate noneMatch() method// of Stream class to check whether no elements of// this stream match the provided predicate // Importing required classesimport java.util.stream.Stream; // Main classclass GFG { // Main driver method public static void main(String[] args) { // Creating a Stream of Strings using of() method // by creating object of Stream of string type Stream<String> stream = Stream.of("Geeks", "fOr", "GEEKSQUIZ", "Lazyroar", "CSe"); // Using Stream noneMatch(Predicate predicate) // and storing the boolean value boolean answer = stream.noneMatch( str -> Character.isUpperCase(str.charAt(1)) && Character.isLowerCase(str.charAt(2)) && str.charAt(0) == 'f'); // Printing the above boolean value on console System.out.println(answer); }} |
false
