package com.example.rest; import java.util.concurrent.CopyOnWriteArrayList; import java.util.stream.Collectors; public class CustomerList { private static final CopyOnWriteArrayList cList = new CopyOnWriteArrayList<>(); static { // Create list of customers cList.add( new Customer.CustomerBuilder().id() .firstName("George") .lastName("Washington") .email("gwash@example.com") .city("Mt Vernon") .state("VA") .birthday("1732-02-23") .build() ); cList.add( new Customer.CustomerBuilder().id() .firstName("John") .lastName("Adams") .email("jadams@example.com") .city("Braintree") .state("MA") .birthday("1735-10-30") .build() ); cList.add( new Customer.CustomerBuilder().id() .firstName("Thomas") .lastName("Jefferson") .email("tjeff@example.com") .city("CharlottesVille") .state("VA") .birthday("1743-04-13") .build() ); cList.add( new Customer.CustomerBuilder().id() .firstName("James") .lastName("Madison") .email("jmad@example.com") .city("Orange") .state("VA") .birthday("1751-03-16") .build() ); cList.add( new Customer.CustomerBuilder().id() .firstName("James") .lastName("Monroe") .email("jmo@example.com") .city("New York") .state("NY") .birthday("1758-04-28") .build() ); } private CustomerList(){} public static CopyOnWriteArrayList getInstance(){ return cList; } public static void testList(){ CopyOnWriteArrayList list = CustomerList.getInstance(); list.stream() .forEach(i -> System.out.println(i)); String cString = list.stream() .map( c -> c.toString()) .collect(Collectors.joining("\n")); System.out.println(cString); } public static void main(String[] args) { CustomerList.testList(); } }