how to set a object from another object inside lambda expression

Anand Kumar :

I am getting a list of managers from DB and now i have to populate each object of this list to another object i.e. employee and return it as a list (employeeList) to its calling function. Both Manager and Employee contains the same fields. I have to achieve this using lambda expression using stream.

Employee.java

public class Employee {
private String name;
private String designation;
private String active;

public String getActive() {
    return active;
}
public void setActive(String active) {
    this.active = active;
}
public String getName() {
    return name;
}
public void setName(String name) {
    this.name = name;
}
public String getDesignation() {
    return designation;
}
public void setDesignation(String designation) {
    this.designation = designation;
}}

Manager.java

public class Manager {
private String name;
private String designation;
private String active;
public String getActive() {
    return active;
}
public void setActive(String active) {
    this.active = active;
}
public String getName() {
    return name;
}
public void setName(String name) {
    this.name = name;
}
public String getDesignation() {
    return designation;
}
public void setDesignation(String designation) {
    this.designation = designation;
}}

ComponentImpl.java

public class ComponentImpl {

public List<Employee> catchAllEmployess () {

    List<Manager> managers = DbOperation.collectManagers(2);
    List<Employee> employees = new ArrayList<>();

    for (Manager manager : managers) {
        Employee employee = new Employee();
        employee.setName(manager.getName());
        employee.setDesignation(manager.getDesignation());
        employee.setActive(manager.getActive());
        employees.add(employee);
    }
    return employees;
}

}

Naman :

You can simplify the expression by including a constructor in Employee class as

Employee(String name, String designation, String active) {
        this.name = name;
        this.designation = designation;
        this.active = active;
    }

which can then be used as

List<Employee> employees = managers.stream()
                .map(manager -> new Employee(manager.getName(), manager.getDesignation(), manager.getActive()))
                .collect(Collectors.toList());