1 public class Input extends Application {
 2 
 3     public static void main(String[] args) {
 4         launch();
 5     }
 6 
 7     @Override
 8     public void start(Stage stage) throws Exception {
 9         // draw UI and set evnetListenners
10         VBox root = new VBox(10);
11         TextField[] inputField = new TextField[3];
12         for (int i = 0; i < 3; i++) {
13             inputField[i] = new TextField();
14         }
15         Button btn = new Button("OK!");
16         btn.setOnAction(new CheackInputsListenner(inputField));
17         root.getChildren().addAll(inputField[0], inputField[1], inputField[2],
18                 btn);
19         root.setAlignment(Pos.CENTER);
20         Scene scene = new Scene(root, 200, 150);
21         stage.setTitle("输入测试");
22         stage.setScene(scene);
23         stage.show();
24     }
25 }
26 
27 class CheackInputsListenner implements EventHandler<ActionEvent> {
28     private TextField[] textFields;
29 
30     CheackInputsListenner(TextField[] tFields) {
31         textFields = tFields;
32     }
33 
34     private boolean inputValid(String input) {
35         if (input == null || input.equals("") || input.length() > 6) {
36             return false;
37         }
38         for (int i = 0; i < input.length(); i++) {
39             if (!Character.isAlphabetic(input.charAt(i))
40                     && !Character.isDigit(input.charAt(i))) {
41                 return false;
42             }
43         }
44         return true;
45     }
46 
47     @Override
48     public void handle(ActionEvent ae) {
49         for (int i = 0; i < textFields.length; i++) {
50             String input = new String(textFields[i].getText());
51             if (!inputValid(input)) {
52                 JOptionPane.showMessageDialog(null, "输入不符合长度为1-6的数字和字母的规则\n"
53                         + "第一个出错的是输入框" + (i + 1), "输入不符合规则",
54                         JOptionPane.ERROR_MESSAGE);
55                 return;
56             }
57         }
58         JOptionPane.showMessageDialog(null, "输入符合规则！", "输入符合规", 1);
59     }
60 }