Driver.java

package com.blabadi.jdk8.optional;

import java.util.ArrayList;
import java.util.List;
import java.util.Optional;

public class Driver {
	private static List<Student> students = new ArrayList<Student>();
	public static void main(String[] args) {
		students.add(new Student("AAA", 1));
		students.add(new Student("BBB", 1));
		students.add(new Student("CCC", 1));
		students.add(new Student("DDD", 1));
		
		int id = findStudentByName("ZZ").map(x-> x.id).orElse(-1);
		System.out.println(id);
	}
	
	
	public static Optional<Student> findStudentByName(String name) 
	{
		return students.stream().filter(x-> x.name.equals("name")).findFirst();
	}
	
	
}

class Student {
	String name;
	int id;
	public Student() {
		
	}
	public Student(String name, int i) {
		this.name = name;
		this.id = i;
	}
	public int getId(){
		return this.id;
	}
}