Java Program to create a new list with values from existing list with Lambda Expressions

Java 8Object Oriented ProgrammingProgramming

To create a new list with values from existing list with Lambda Expressions, the following is an example.

Here, we are displaying the name of Employees. Therefore, we have created an Employee class as well −

List<Employee>emp = Arrays.asList(new Employee("Jack", 29, "South"), new Employee("Tom", 24, "North"), new Employee("Harry", 35, "West"),new Employee("Katie", 32, "East"));

Use Lambda to crate anew list from existing list with Lambda Expressions −

List<String>res = emp.stream().map(u ->u.displayEmpName()).collect(Collectors.toList());

Let us see the complete example −

Example

 Live Demo

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.function.Function;
import java.util.stream.Collectors;
public class Demo {
   public static void main(String args[]) {
      List<Employee>emp = Arrays.asList(new Employee("Jack", 29, "South"), new Employee("Tom", 24, "North"),
          new Employee("Harry", 35, "West"),new Employee("Katie", 32, "East"));
      List<String>res = emp.stream().map(u ->u.displayEmpName()).collect(Collectors.toList());
      System.out.println("Employee Names = "+res);
   }
}
class Employee {
   private String emp_name;
   private int emp_age;
   private String emp_zone;
   public Employee(String emp_name, int emp_age, String emp_zone) {
      this.emp_name = emp_name;
      this.emp_age = emp_age;
      this.emp_zone = emp_zone;
   }
   public String displayEmpName() {
      return this.emp_name;
   }
}

Output

Employee Names = [Jack, Tom, Harry, Katie]
raja
Published on 24-Apr-2019 12:53:29
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