Binding BeanItemContainer within is array to the table

Question

I have BeanItemContainer which I would like to bind as a data source in my table. BeanItemContainer has inside bean within is an array. How could I do this ?

Below is my bean (POJO) within is nested the array:

private EmployeesArray[] employeesArray;

public EmployeesArray[] getEmployeesArray() {
    return employeesArray;
}

public void setEmployeesArray (EmployeesArray[] employeesArray) {
    this.employeesArray = employeesArray;
}

public EmployeesListPOJO(){ 
}

And here is the nested array:

private String lastname;
private String firstname;

public String getLastname () {
    return lastname;
}

public void setLastname (String lastname) {
    this.lastname = lastname;
}

public String getFirstname () {
    return firstname;
}

public void setFirstname (String firstname) {
    this.firstname = firstname;
}

@Override
public String toString() {
    return "ClassPojo [lastname = "+lastname+", firstname = "+firstname+"]";
}

public EmployeesArray(){
}

And here's my attempt to bind it to the table:

BeanItemContainer<EmployeesListPOJO> container = new BeanItemContainer<EmployeesListPOJO>(EmployeesListPOJO.class);

Table table = new Table();
table.setContainerDataSource(container);
table.setVisibleColumns(new String[] {"employeesArray"});
table.setColumnHeader("employeesArray", "First name", "Last name");`

I would like to have two column headers in my table: "First name" and "Last name" which are associated to fields firstname and lastname in the array.

Answer 1

I'm not trying to be condescending, but I believe there are a few issues with this code, so let's tackle them 1 by 1:

1. The EmployeesArray class should probably be named Employee since it holds employee data, and your array variable would become Employee[] employees.

2. Since you want to display employees in your table, you should have a corresponding container: BeanItemContainer<Employee> container = new BeanItemContainer<>(Employee.class);

3. If EmployeesListPOJO can not be changed, you'll then need to iterate over the array and add each employee bean to the container with container.addBean(employees[i]);. Or, if you can change it to a collection instead you can just simply call container.addAll(employees);. Also probably EmployeesListPOJO should have a friendlier name but I don't know the whole context so it's up to you

Putting it all together:

    // create the table
    Table table = new Table()

    // and the appropriate data holder 
    BeanItemContainer<Employee> container = new BeanItemContainer<>(Employee.class);
    table.setContainerDataSource(container);

    // set desired headers
    table.setColumnHeaders("First name", "Last name");

    // get all of the employees to display
    employees = employeesListPOJO.getEmployeesArray();

    // add each employee to the container
    for (int i = 0; i < employees.length; i++) {
        container.addBean(employees[i]);
    }

    // or if you can get a collection/list of employees
    // container.addAll(employeesListPOJO.getEmployees());

With:

public class Employee {

    private String lastname;
    private String firstname;

    public Employee(String lastname, String firstname) {
        this.lastname = lastname;
        this.firstname = firstname;
    }

    public String getLastname () {
        return lastname;
    }

    public void setLastname (String lastname) {
        this.lastname = lastname;
    }

    public String getFirstname () {
        return firstname;
    }

    public void setFirstname (String firstname) {
        this.firstname = firstname;
    }

    @Override
    public String toString() {
        return "Employee [lastname = "+lastname+", firstname = "+firstname+"]";
    }
}

Should result in

P.S. 1: You can also find more information in the Vaadin documentation

P.S. 2: If you're working with the latest Vaadin versions (7.4.0 +) and depending on your needs, I suggest taking a look at the newer Grid component which is supposed to be more flexible than its older counterpart the table. You can see its features in action on the sampler site

Cheers