Stream noneMatch() method in Java with examples

Last Updated : 06 Dec, 2018

Stream noneMatch(Predicate predicate) 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.
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.

Example 1 : To check that there is no string of length 4.

// Java code for Stream noneMatch
// (Predicate predicate) to check whether
// no 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("CSE", "C++",
                                        "Jav", "DS");
  
        // Using Stream noneMatch(Predicate predicate)
        boolean answer = stream.noneMatch(str -> (str.length() == 4));
  
        // Displaying the result
        System.out.println(answer);
    }
}

Output:

true

Example 2 : To check that there is no element less than 0.

// Java code for Stream noneMatch
// (Predicate predicate) to check whether
// no 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(4, 0, 6, 2);
  
        // Using Stream noneMatch(Predicate predicate)
        boolean answer = list.stream().noneMatch(num -> num < 0);
  
        // Displaying the result
        System.out.println(answer);
    }
}

Output:

true

Example 3 : To check that there is no element with required characters at required position.

// Java code for Stream noneMatch
// (Predicate predicate) to check whether
// no 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", "GeeksforGeeks", "CSe");
  
        // Using Stream noneMatch(Predicate predicate)
        boolean answer = stream.noneMatch
                         (str -> Character.isUpperCase(str.charAt(1)) 
                         && Character.isLowerCase(str.charAt(2)) 
                         && str.charAt(0) == 'f');
  
        // Displaying the result
        System.out.println(answer);
    }
}

Output:

false

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