Stream allMatch(Predicate predicate) returns whether all 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. Syntax :
boolean allMatch(Predicate<? super T> predicate) Where, T is the type of the input to the predicate and the function returns true if either all 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. Once any function is done using the stream it can’t be used again until it is re-initialize. Example 1 : allMatch() function to check whether all elements are divisible by 3.
Java
// Java code for Stream allMatch// (Predicate predicate) to check whether// all elements of this stream match// the provided predicate.import java.util.*;class GFG { // Driver code public static void main(String[] args) { // Creating a list of Integers List<Integer> list = Arrays.asList(3, 4, 6, 12, 20); // Check if all elements of stream // are divisible by 3 or not using // Stream allMatch(Predicate predicate) boolean answer = list.stream().allMatch(n-> n % 3 ==0); // Displaying the result System.out.println(answer);}} |
Output :
false
Example 2 : allMatch() function to check whether strings have length greater than 2.
Java
// Java code for Stream allMatch// (Predicate predicate) to check whether// all elements of this stream match// the provided predicate.import java.util.stream.Stream;class GFG { // Driver code public static void main(String[] args) { // Creating a Stream of Strings Stream<String> stream = Stream.of("Geeks", "for", "GeeksQuiz", "Lazyroar"); // Check if all elements of stream // have length greater than 2 using // Stream allMatch(Predicate predicate) boolean answer = stream.allMatch(str -> str.length() > 2); // Displaying the result System.out.println(answer);}} |
Output :
true
Example 3 : allMatch() function to check whether all strings have UpperCase character at 1st index.
Java
// Java code for Stream allMatch// (Predicate predicate) to check whether// all elements of this stream match// the provided predicate.import java.util.stream.Stream;class GFG { // Driver code public static void main(String[] args) { // Creating a Stream of Strings Stream<String> stream = Stream.of("Geeks", "for", "GeeksQuiz", "Lazyroar"); // Check if Character at 1st index is // UpperCase in all strings or not using // Stream allMatch(Predicate predicate) boolean answer = stream.allMatch(str-> Character .isUpperCase(str.charAt(1))); // Displaying the result System.out.println(answer);}} |
Output :
false
Example 4 : Multiple function done using same stream
Java
// In case we want multiple function to be done.import java.util.stream.IntStream;public class MultipleStreamFunction { public static void main(String[] args) { final String sample = "Om Sarve Bhavantu Sukhinah"; // converting to Ascii IntStream intstreams = sample.chars(); // All match to check if all Ascii value greater than 100 boolean answer = intstreams.allMatch(c -> c > 100); System.out.println(answer); // Need to initialize the stream again // to avoid runtime exception intstreams = sample.chars(); // All match to check if all Ascii value greater than 31 answer = intstreams.allMatch(c -> c > 31); System.out.println(answer); }} |
Output :
false true
