Apache Common MultiValueMap iteration

The problem you are having is caused by the fact that one employee should not appear twice in the same collection. If you are storing two values ​​under the same key in a MultiValueMap than the thesis of different values ​​(although they are accessed by the same key).

You should migrate your data model to a more object oriented model and not use a key storage container located inside another key store container (map inside map).

Consider the following model using only Set / List. The values ​​are differentiated based on equals / hashcode. If you use List, you can have many employees within the company (they can have the same name if you really need it). Why are you complicating it with MultiValueMap?

public class AbcTest {
  public static void main(String[] args) {

    Address address1 = new Address("street1");
    Address address2 = new Address("street2");

    Employee employee1 = new Employee("employee1");
    employee1.getAddresses().add(address1);
    employee1.getAddresses().add(address2);

    Employee employee2 = new Employee("employee2");
    employee2.getAddresses().add(address2);

    Company companyA = new Company("compA");

    companyA.getEmployees().add(employee1);
    companyA.getEmployees().add(employee1); // you can add employee to the list as many times as you want, if you really need this?
    companyA.getEmployees().add(employee2);

    // now to get the employee with give name simly iterate over list of employees

    Iterator<Employee> employeeIt = companyA.getEmployees().iterator();


    Employee wantedEmployee = null;

    while (employeeIt.hasNext() && (wantedEmployee == null)) {
      Employee next = employeeIt.next();

      if (next.getName().equals("employee1")) {
        wantedEmployee = next;
      }
    }

    System.out.println(wantedEmployee);


  }



}


class Company {
  final String name;

  final List<Employee> employees;

  Company(String name) {
    this.name = name;
    this.employees = new ArrayList<>();
  }

  public String getName() {
    return name;
  }

  public List<Employee> getEmployees() {
    return employees;
  }

  @Override
  public boolean equals(Object o) {
    if (this == o) {
      return true;
    }
    if ((o == null) || (getClass() != o.getClass())) {
      return false;
    }

    Company company = (Company) o;

    if ((employees != null) ? (!employees.equals(company.employees)) : (company.employees != null)) {
      return false;
    }
    if ((name != null) ? (!name.equals(company.name)) : (company.name != null)) {
      return false;
    }

    return true;
  }

  @Override
  public int hashCode() {
    int result = (name != null) ? name.hashCode() : 0;
    result = (31 * result) + ((employees != null) ? employees.hashCode() : 0);
    return result;
  }
}

class Employee {
  final String name;
  final Set<Address> addresses;

  Employee(String name) {
    this.name = name;
    this.addresses = new HashSet<>();
  }

  public String getName() {
    return name;
  }

  public Set<Address> getAddresses() {
    return addresses;
  }

  @Override
  public String toString() {
    return "Employee{" +
      "name='" + name + '\'' +
      '}';
  }

  @Override
  public boolean equals(Object o) {
    if (this == o) {
      return true;
    }
    if ((o == null) || (getClass() != o.getClass())) {
      return false;
    }

    Employee employee = (Employee) o;

    if ((addresses != null) ? (!addresses.equals(employee.addresses)) : (employee.addresses != null)) {
      return false;
    }
    if ((name != null) ? (!name.equals(employee.name)) : (employee.name != null)) {
      return false;
    }

    return true;
  }

  @Override
  public int hashCode() {
    int result = (name != null) ? name.hashCode() : 0;
    result = (31 * result) + ((addresses != null) ? addresses.hashCode() : 0);
    return result;
  }
}


class Address {
  final String street;

  Address(String street) {
    this.street = street;
  }

  public String getStreet() {
    return street;
  }

  @Override
  public boolean equals(Object o) {
    if (this == o) {
      return true;
    }
    if ((o == null) || (getClass() != o.getClass())) {
      return false;
    }

    Address address = (Address) o;

    if ((street != null) ? (!street.equals(address.street)) : (address.street != null)) {
      return false;
    }

    return true;
  }

  @Override
  public int hashCode() {
    return (street != null) ? street.hashCode() : 0;
  }
}