I am following ST's ST25SDK demo example and I am getting these errors:
Exception in Application start method
java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at com.sun.javafx.application.LauncherImpl.launchApplicationWithArgs(LauncherImpl.java:389)
at com.sun.javafx.application.LauncherImpl.launchApplication(LauncherImpl.java:328)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at sun.launcher.LauncherHelper$FXHelper.main(LauncherHelper.java:767)
Caused by: java.lang.RuntimeException: Exception in Application start method
at com.sun.javafx.application.LauncherImpl.launchApplication1(LauncherImpl.java:917)
at com.sun.javafx.application.LauncherImpl.lambda$launchApplication$155(LauncherImpl.java:182)
at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.NullPointerException
at com.st.myst25app.MainApp.initStage(MainApp.java:47)
at com.st.myst25app.MainApp.start(MainApp.java:22)
at com.sun.javafx.application.LauncherImpl.lambda$launchApplication1$162(LauncherImpl.java:863)
at com.sun.javafx.application.PlatformImpl.lambda$runAndWait$175(PlatformImpl.java:326)
at com.sun.javafx.application.PlatformImpl.lambda$null$173(PlatformImpl.java:295)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.javafx.application.PlatformImpl.lambda$runLater$174(PlatformImpl.java:294)
at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:95)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.lambda$null$148(WinApplication.java:191)
... 1 more
Exception running application com.st.myst25app.MainApp
The error occurs at this line in the main app (MainApp.java line: 47) Which is saying it is caused by a java.lang.NullPointerException :
mNfcTagController.setMainApp(this);
When I comment out this line, there's no errors but I need the controller to have access to the main app.
I am using a 32-bit jdk, which is required to run dll files and the version I am using is jdk1.8.0_144. I don't have any VM arguments.
Any ideas of what I may be missing or what I need to add to fix this issue?
Here is my main app shown below:
package com.st.myst25app;
import java.io.IOException;
import com.st.myst25app.view.NfcTagController;
import com.st.st25pc.model.readers.RFGenericReader;
import com.st.st25pc.model.readers.st.STReader;
import javafx.application.Application;
import javafx.beans.property.SimpleStringProperty;
import javafx.beans.property.StringProperty;
import javafx.fxml.FXMLLoader;
import javafx.scene.Scene;
import javafx.scene.layout.AnchorPane;
import javafx.stage.Stage;
public class MainApp extends Application {
private Stage mPrimaryStage;
private RFGenericReader mActiveRFReader = null;
private StringProperty mReaderStatus = new SimpleStringProperty();
@Override
public void start(Stage primaryStage) {
mPrimaryStage = primaryStage;
mPrimaryStage.setTitle("MyST25App");
initStage();
// Scan for USB reader and open device
scanForReaders();
}
public static void main(String[] args) {
launch(args);
}
/**
* Initializes the NfcTagView Stage
*/
public void initStage() {
try {
// Load root layout from FXML file
FXMLLoader loader = new FXMLLoader();
loader.setLocation(MainApp.class.getResource("view/NfcTagView.fxml"));
AnchorPane rootLayout = (AnchorPane) loader.load();
// Show the scene containing the root layout
Scene scene = new Scene(rootLayout);
mPrimaryStage.setScene(scene);
// Give the controller access to the main app
NfcTagController mNfcTagController = loader.getController();
mNfcTagController.setMainApp(this);
// Display Stage on screen
mPrimaryStage.show();
} catch (IOException e) {
e.printStackTrace();
}
}
/**
* Scan USB ports for readers
*/
public void scanForReaders() {
// Try to instantiate a STReader (CR95HF, ST25R3911B-DISCO or ST25R3916-DISCO) to determine if one
//is connected
STReader stReader = new STReader();
if (stReader.connect()) {
// Now able to communicate with the reader
mActiveRFReader = stReader;
}
if (mActiveRFReader != null) {
setReaderStatus(stReader.getName() + " connected");
} else {
setReaderStatus("No reader is connected");
}
}
public final StringProperty readerStatusProperty() {
return mReaderStatus;
}
public final String getReaderStatus() {
return readerStatusProperty().get();
}
public final void setReaderStatus(final String mReaderStatus) {
readerStatusProperty().set(mReaderStatus);
}
}
Here is the Controller code:
package com.st.myst25app.view;
import com.st.myst25app.MainApp;
/**
* @author STMicroelectronics
*
*/
import javafx.fxml.FXML;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.control.Label;
public class NfcTagController {
@FXML
private Button discoverButton;
@FXML
private Label tagUidLabel;
@FXML
private Label tagSizeLabel;
@FXML
private Label writeStatusLabel;
@FXML
private Label readerStatusLabel;
// Reference to the main application
private MainApp mainApp;
/**
* Initializes the controller class.
* This method is automatically called after the fxml file is loaded.
*/
@FXML
private void initialize () {
tagUidLabel.setText("No tag discovered");
tagSizeLabel.setText("No tag discovered");
writeStatusLabel.setText("");
readerStatusLabel.setText("No reader is connected");
}
/**
* setMainApp is called by the main application to give a reference of itself to the
controller.
*
* @param mainApp
*/
public void setMainApp(MainApp mainApp) {
this.mainApp = mainApp;
//Bind reader connection status to a label to display the updated value whenever
there is a change
readerStatusLabel.textProperty().bind(mainApp.readerStatusProperty());
}
}
FXML file:
<?xml version="1.0" encoding="UTF-8"?>
<?import javafx.scene.control.Button?>
<?import javafx.scene.control.Label?>
<?import javafx.scene.layout.AnchorPane?>
<?import javafx.scene.layout.ColumnConstraints?>
<?import javafx.scene.layout.GridPane?>
<?import javafx.scene.layout.RowConstraints?>
<AnchorPane xmlns="http://javafx.com/javafx/8" xmlns:fx="http://javafx.com/fxml/1">
<children>
<GridPane hgap="5.0" layoutX="12.0" layoutY="87.0" AnchorPane.bottomAnchor="10.0"
AnchorPane.leftAnchor="10.0" AnchorPane.rightAnchor="10.0" AnchorPane.topAnchor="10.0">
<columnConstraints>
<ColumnConstraints hgrow="SOMETIMES" maxWidth="284.0" minWidth="0.0" prefWidth="90.0" />
<ColumnConstraints hgrow="SOMETIMES" minWidth="10.0" prefWidth="300.0" />
</columnConstraints>
<rowConstraints>
<RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
<RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
<RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
<RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
</rowConstraints>
<children>
<Button fx:id="discoverButton" mnemonicParsing="false" prefWidth="90.0" text="Discover Tag" />
<Label text="Detects Iso15693/NFC Forum Type 5 tag" GridPane.columnIndex="1" />
<Label text="Tag UID:" GridPane.halignment="RIGHT" GridPane.rowIndex="1" />
<Label fx:id="tagUidLabel" text="UID" GridPane.columnIndex="1" GridPane.rowIndex="1" />
<Label text="EEPROM size:" GridPane.halignment="RIGHT" GridPane.rowIndex="2" />
<Label fx:id="tagSizeLabel" text="Size" GridPane.columnIndex="1" GridPane.rowIndex="2" />
<Button fx:id="writeNdefButton" mnemonicParsing="false" prefWidth="90.0" text="Write Uri"
GridPane.rowIndex="3" />
<Label fx:id="writeStatusLabel" text="Status" GridPane.columnIndex="1" GridPane.rowIndex="3" />
<Label fx:id="readerStatusLabel" text="Reader Status" GridPane.columnIndex="1"
GridPane.halignment="RIGHT" GridPane.rowIndex="4" />
</children>
</GridPane>
</children>
</AnchorPane>
