即使文件路径正确，也不会加载FXML文件

Question

I am trying to load an FXML file:

URL url = getClass().getClassLoader().getResource("/frontEnd/fxml/ModeScreen.fxml");

try {
    this.value = FXMLLoader.load(url);
} catch (IOException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
}

But when I run, I get:

NullPointerException: Location is required

the path to my fxml file is:

src/frontEnd/fxml/ModeScreen.fxml

and the path to my class file is:

src/frontEnd/ModeScreen.java

this.value extends AnchorPane and the FXML file's root is an AnchorPane.

I checked and made sure that all of these files are in the bin folder and it doesn't run in either a jar file or Eclipse

I have also tried to use the following paths:

frontEnd/fxml/ModeScreen.fxml
../frontEnd/fxml/ModeScreen.fxml
src/frontEnd/fxml/ModeScreen.fxml
/src/frontEnd/fxml/ModeScreen.fxml
/fxml/ModeScreen.fxml
fxml/ModeScreen.fxml

I have also tried using getResourceAsStream.toString

file structure is as follows:

bin

    application

        Main

    frontEnd

        controllers

        fxml<---<all the fxml files are in here. I checked too.>

        ModeScreen.class

There must be some tiny thing I am doing wrong.

Answer 1

The problem in here is that you are appending a / , when you are already using a ClassLoader 's getResource() .

You should never use a / at the beginning of a ClassLoader path is because all ClassLoader paths are absolute .

You can definitely use Class 's getResource() with a URL which starts with / , because before it delegates down to the classloader, it creates an absolute URL.

From the JavaDocs :

Before delegation, an absolute resource name is constructed from the given resource name using this algorithm:

• If the name begins with a '/' ('\/'), then the absolute name of the resource is the portion of the name following the '/'.

The following are valid url :

Using ClassLoader :

URL url = getClass().getClassLoader().getResource("frontEnd/fxml/ModeScreen.fxml");

Using Class :

URL url = getClass().getResource("/frontEnd/fxml/ModeScreen.fxml");