How do i get rid of these (unchecked call) warnings?

java generics javafx warnings unchecked
Markus Paul picture Markus Paul · Jun 25, 2015 · Viewed 7k times · Source 
warning: [unchecked] unchecked call to setCellValueFactory(Callback<CellDataFeatures<S,T>,ObservableValue<T>>) as a member of the raw type TableColumn column1.setCellValueFactory(new PropertyValueFactory<String, State>("name"));   where S,T are type-variables:
    S extends Object declared in class TableColumn
    T extends Object declared in class TableColumn

code:

column1.setCellValueFactory(new PropertyValueFactory<>("name"));

warning: [unchecked] unchecked call to add(E) as a member of the raw type List
            transitionTable.getColumns().add(column1);
  where E is a type-variable:
    E extends Object declared in interface List

code:

transitionTable.getColumns().add(column1);

warning: [unchecked] unchecked call to setAll(Collection<? extends E>) as a member of the raw type ObservableList
        automatonSelection.getItems().setAll(automatonManager.getMachines());
  where E is a type-variable:
    E extends Object declared in interface ObservableList

code:

automatonSelection.getItems().setAll(automatonManager.getMachines());

automatonSelection is a ComboBox and getMachines() returns a LinkedList of the type Automaton

warning: [unchecked] unchecked call to addListener(ChangeListener<? super T>) as a member of the raw type ObservableValue
        automatonSelection.valueProperty().addListener((ObservableValue observable,
  where T is a type-variable:
    T extends Object declared in interface ObservableValue

code:

automatonSelection.valueProperty().addListener((ObservableValue observable,
            Object oldValue, Object newValue) -> {
        stateChanged();
    });

I tried to fix most of those warnings and managed to do so by adding generics, but I can't see how to fix those other 4 warnings.

Answer

James_D picture James_D · Jun 25, 2015

Don't declare your TableViews and TableColumns as raw types.

In other words, instead of

TableView personTable ;
TableColumn firstNameColumn ;

use

TableView<Person> personTable ;
TableColumn<Person, String> firstNameColumn ;

etc.

Don't suppress these warnings, they will help you debug problems.

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