Coding Challenge: Java Functional Programming

✒ Reference: Java Functional Programming (Part 1: The Beginning)

Functional Programming

Mapping Functions

Function <MyObject, String> f = p -> p.toString();
String myString = f.apply(myObject); 
//Stores whatever the toString() of myObject is in myString

Given this POJO, write a Function (with the appropriate types) that returns true if a given student is “John Smith” with a student number of “js123” (otherwise return false).

public class Student {
  private final String firstName;
  private final String lastName;
  public final String studentNumber;
  public String getFullName() {
    return firstName + " " + lastName;
  }
  public String getCommaName() {
    return lastName + ", " + firstName;
  }
}

Best Solution:

import java.util.function.Function;

public class FunctionalProgramming {
  public static Function<Student, Boolean> f = s -> 
    "John Smith".equals(s.getFullName()) &&
    "js123".equals(s.studentNumber);
}

• == operators are used for reference comparison (address comparison) and .equals() method is used for content comparison!