OrElseGetExample

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package com.mycompany.mavenproject1;

import java.util.Optional;

/**
*
* @author VenkPi
*/
public class OrElseGet {

// public static void main(String[] args) {
// validate(Optional.empty());
// validate(Optional.of("VENKATA"));
//
// }
public Optional<String> findMyPhone(int phoneId) {
return phoneId == 10
? Optional.of("MyCheapPhone")
: Optional.empty();
}

public String buyNewExpensivePhone() {
System.out.println("\tGoing to a very far store to buy a new expensive phone");
return "NewExpensivePhone";
}

public static void main(String[] args) {
OrElseGet test = new OrElseGet();
String phone;
System.out.println("------------- Scenario 1 - orElse() --------------------");
System.out.println(" 1.1. Optional.isPresent() == true");
phone = test.findMyPhone(10).orElse(test.buyNewExpensivePhone());
System.out.println("\tUsed phone: " + phone + "\n");

System.out.println(" 1.2. Optional.isPresent() == false");
phone = test.findMyPhone(-1).orElse(test.buyNewExpensivePhone());
System.out.println("\tUsed phone: " + phone + "\n");

System.out.println("------------- Scenario 2 - orElseGet() --------------------");
System.out.println(" 2.1. Optional.isPresent() == true");
// Can be written as test::buyNewExpensivePhone
phone = test.findMyPhone(10).orElseGet(() -> test.buyNewExpensivePhone());
System.out.println("\tUsed phone: " + phone + "\n");

System.out.println(" 2.2. Optional.isPresent() == false");
phone = test.findMyPhone(-1).orElseGet(() -> test.buyNewExpensivePhone());
System.out.println("\tUsed phone: " + phone + "\n");
}
}