BiPredicate in Java 8 with examples | test(), and(), or() and negate() methods

What is BiPredicate?

BiPredicate is same as Predicate, but it accepts two arguments. BiPredicate is Functional interface which accepts two arguments and return boolean value.

BiPredicate contains following methods : 

1. test() : abstarct method
   
2. and() : default method
3. or() : default method
4. negate() : default method

So lets see examples of BiPredciate

Example 1 : Check even number using BiPredicate

import java.util.function.BiPredicate;

public class BiPredicateDemo {

    public static void main(String[] args) {
        
        BiPredicate<Integer, Integer> isEven = (number1, number2) -> {
            return (number1 + number2) % 2 == 0;
        };
        
        System.out.println(isEven.test(5, 6));
        System.out.println(isEven.test(5, 5));

    }

}
Output :
false
true

and() method :

and() predicate retruns true when both predicate conditions becomes true. Lets see example of and() method.

Example 2 : BiPredicate and() method

import java.util.function.BiPredicate;

public class BiPredicateDemo {

    public static void main(String[] args) {
    
        BiPredicate<String, String> biPredicate1 = (str1, str2) -> 
            str1.length() == str2.length();
        
        BiPredicate<String, String> biPredicate2 = (str1, str2) -> 
            str1.equals(str2);
            
        System.out.println(biPredicate1.and(biPredicate2).test("Programming", "programming"));
        System.out.println(biPredicate1.and(biPredicate2).test("Java", "Java"));
            
    }
}
Output :
false
true

In first result, string length is same but it is not equals so it is returning false. In second result, both string are same length and equals so we are getting true as result.

or() method :

or() predicate returns true when one of predicates becomes true.

Example 3 : BiPredicate or() method

import java.util.function.BiPredicate;

public class BiPredicateDemo {

    public static void main(String[] args) {
    
        BiPredicate<String, String> biPredicate1 = (str1, str2) -> 
            str1.length() == str2.length();
        
        BiPredicate<String, String> biPredicate2 = (str1, str2) -> 
            str1.equals(str2);
            
        System.out.println(biPredicate1.or(biPredicate2).test("Programming", "programming"));
        System.out.println(biPredicate1.or(biPredicate2).test("Java", "Java"));

    }
}
output :
true
true

Example 4 : BiPredicate with Objects

Person.java 
public class Person {
    
    String name;
    Integer age;
    
    public Person(String name, Integer age) {
        super();
        this.name = name;
        this.age = age;
    }
    
    public String getName() {
        return name;
    }
    
    public void setName(String name) {
        this.name = name;
    }
    
    public Integer getAge() {
        return age;
    }
    
    public void setAge(Integer age) {
        this.age = age;
    }
    
}

BiPredicateDemo.java
import java.util.Arrays;
import java.util.List;
import java.util.function.BiPredicate;

public class BiPredicateDemo {

    public static void main(String[] args) {
    
        List<Person> personList = Arrays.asList(
            new Person("Person 1" , 22),
            new Person("Person 2" , 40),
            new Person("Person 3" , 18),
            new Person("Person 4" , 34),
            new Person("Person 5" , 25));    

        BiPredicate<Person, Integer> biPredicate1 = (person1, age) -> {
            return  (person1.getAge() > age);
        };
        
        
        for (Person person : personList) {
            System.out.println(person.getName() + " = " + biPredicate1.test(person, 25));
        }      
    
    }
    
}
Output :
Person 1 = false
Person 2 = true
Person 3 = false
Person 4 = true
Person 5 = false

Happy Coding.

Other java 8 articles :

• Lambda Expression in Java 8 
• Consumer and Biconsumer In Java 8