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package streams;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.stream.Collectors;
import java.util.stream.Stream;
public class Main {
public static void main(String[] args) {
CustomerService customerService = new CustomerService();
List<Customer> customers = customerService.prepareCustomerList();
Stream<Customer> customerStream = Stream.of(new Customer("bilisim.io", 5, new ArrayList<Order>()));
List<Integer> ageList = new ArrayList<>();
ageList.add(25);
ageList.add(28);
ageList.add(15);
ageList.add(35);
ageList.add(45);
ageList.add(20);
ageList.forEach(System.out::println);
ageList.stream().filter(age -> age > 35).forEach(System.out::println);
ageList.stream().filter(age -> age > 35).toList();
for (Integer age : ageList) {
if (age > 35) {
System.out.println(age);
}
}
customers.stream().forEach(customer -> {
customer.age += 3;
});
customers.stream().forEach(customer -> customer.age += 3);
customers.stream().forEach(CustomerService::incrementCustomerAge);
List<String> customerNames = customers.stream().map(customer -> customer.name)
.filter(customerName -> customerName.startsWith("c")).toList();
customerNames.forEach(System.out::println);
Set<String> customerNamesSet = customers.stream().map(customer -> customer.name)
.filter(customerName -> customerName.startsWith("c")).collect(Collectors.toSet());
List<String> customerNamesList = customers.stream().map(customer -> customer.name)
.filter(customerName -> customerName.startsWith("c")).collect(Collectors.toList());
Map<String, Integer> customerNamesMap = customers.stream().filter(customer -> customer.age > 35)
.filter(customer -> customer.name.startsWith("c"))
.collect(Collectors.toMap(Customer::getName, Customer::getAge));
List<String> collect = customers.stream()
.filter(customer -> customer.age > 18)
.peek(CustomerService::incrementCustomerAge)
.map(customer -> customer.name)
.peek(customerName -> customerName = customerName.trim())
.filter(customerName -> customerName.startsWith("c"))
.peek(customerName -> customerName.replace("c", "C"))
.collect(Collectors.toList());
Customer firstCustomer = customers.stream().filter(customer -> customer.age > 18)
.peek(CustomerService::incrementCustomerAge).findFirst()
.orElseThrow(() -> new RuntimeException("Customer not found"));
int maxAge = customers.stream().map(Customer::getAge).reduce(0, Math::max).intValue();
System.out.println("max age: " + maxAge);
}
}
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