没有括号的泛型静态方法，例如在JavaFX 8中

Question

I've defined a GUI within a FXML file and have the following code in the corresponding controller:

@FXML
private TableColumn<Abnormality, String> abnormalityTableViewStatusTableColumn;

later in the initialize() -method I have:

abnormalityTableViewStatusTableColumn.setCellFactory(
            ComboBoxTableCell.<Abnormality, String> forTableColumn("Option1", "Option2", "Option3"));

( API TableColumn - method setCellFactory and API ComboBoxTableCell - method forTableColumn )

But the compiler would also accept

abnormalityTableViewStatusTableColumn.setCellFactory(
            ComboBoxTableCell.forTableColumn("Option1", "Option2", "Option3"));

without the generic brackets.

Does the compiler automatically resolve the types in the second case?

Thank you for your help!

Answer 1

Yes; Java 8 contains some improvements over previous versions in type-inference. In Java 8 the compiler is able to infer from the context (you are passing the result of forTableColumn into a method that is expecting a Callback<TableColumn<Abnormality, String>, TableCell<Abnormality, String>> ) that the type for the generic method is <Abnormality, String> . Because the compiler can make this inference, explicitly providing the types is not required.