We can split a collection into multiple subcollections using a Predicate, Lambda, Streams and the Collectors.partitioningBy() method.
Example:
package org.code2care.examples;
import java.util.*;
import java.util.function.Predicate;
import java.util.stream.Collectors;
public class SplitCollectionByPredicateExample {
public static void main(String... args) {
List<Integer> numbers = Arrays.asList(1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
Predicate<Integer> isEven = num -> num % 2 == 0;
Map<Boolean, List<Integer>> evenOddMap = numbers.stream()
.collect(Collectors.partitioningBy(isEven));
List<Integer> evenNumbers = evenOddMap.get(true);
List<Integer> oddNumbers = evenOddMap.get(false);
System.out.println("Even Numbers: " + evenNumbers);
System.out.println("Odd Numbers: " + oddNumbers);
}
}
Output:
If you are working with Set then your code will be as follows.
Set<Integer> numbers = new HashSet<>(Arrays.asList(1, 2, 3, 4, 5, 6, 7, 8, 9, 10));
Predicate<Integer> isEven = num -> num % 2 == 0;
Set<Integer> evenNumbers = numbers.stream()
.filter(isEven)
.collect(Collectors.toSet());
Facing issues? Have Questions? Post them here! I am happy to answer!
Author Info:
Rakesh (He/Him) has over 14+ years of experience in Web and Application development. He is the author of insightful How-To articles for Code2care.
Follow him on: X
You can also reach out to him via e-mail: rakesh@code2care.org
More Posts related to Java,
- Get the current timestamp in Java
- Java Stream with Multiple Filters Example
- Java SE JDBC with Prepared Statement Parameterized Select Example
- Fix: UnsupportedClassVersionError: Unsupported major.minor version 63.0
- [Fix] Java Exception with Lambda - Cannot invoke because object is null
- 7 deadly java.lang.OutOfMemoryError in Java Programming
- How to Calculate the SHA Hash Value of a File in Java
- Java JDBC Connection with Database using SSL (https) URL
- How to Add/Subtract Days to the Current Date in Java
- Create Nested Directories using Java Code
- Spring Boot: JDBCTemplate BatchUpdate Update Query Example
- What is CA FE BA BE 00 00 00 3D in Java Class Bytecode
- Save Java Object as JSON file using Jackson Library
- Adding Custom ASCII Text Banner in Spring Boot Application
- [Fix] Java: Type argument cannot be of primitive type generics
- List of New Features in Java 11 (JEPs)
- Java: How to Add two Maps with example
- Java JDBC Transition Management using PreparedStatement Examples
- Understanding and Handling NullPointerException in Java: Tips and Tricks for Effective Debugging
- Steps of working with Stored Procedures using JDBCTemplate Spring Boot
- Java 8 java.util.Function and BiFunction Examples
- The Motivation Behind Generics in Java Programming
- Get Current Local Date and Time using Java 8 DateTime API
- Java: Convert Char to ASCII
- Deep Dive: Why avoid java.util.Date and Calendar Classes
More Posts:
- How to Restart or Reload Nginx Server Service on Linux - Linux
- What does has notifications silenced in Messages App mean in iPhone - iOS
- New Mac? How to install Native Chrome on M1/M2 Mac - Chrome
- Java monitoring and management console [jconsole] - Java
- How to Decode Base64 Data String in Python - Python
- Java: Collect Stream as ArrayList or LinkedList - Java
- How to install Java 11 on Mac - Java
- IntelliJ Keyboard Shortcut to remove unused imports [Java] - Java