JavaFX Reader to Text Area

FileManager.java

package org.gnusosa;


import java.io.FileNotFoundException;
import java.util.ArrayList;
import java.util.Scanner;

public class ReadText extends FileManager {
    private Scanner scanner;

    public Scanner getScanner() {
        return scanner;
    }


    public ReadText(Scanner scanner) {
        this.scanner = scanner;
    }

    public ReadText(String path) throws FileNotFoundException {
        super(path);
        this.scanner = new Scanner(this.getFileHandler());

    }

    @Override
    public String getLine(int lineNumber) {
        String[] stringArray = this.getArrayOfLines();
        this.getScanner().reset();
        return stringArray[lineNumber];
    }

    @Override
    public String getAll() {
        StringBuffer sbuffer = new StringBuffer();
        while(this.getScanner().hasNext()) {
            sbuffer.append(this.getScanner().nextLine() + "\n");
        }

        this.getScanner().reset();
        return sbuffer.toString();
    }

    @Override
    public String[] getArrayOfLines() {
        ArrayList<String> stringArray = new ArrayList<String>();
        while(this.getScanner().hasNextLine()) {
            stringArray.add(this.getScanner().nextLine());
        }

        this.getScanner().reset();

        String[] stockArr = new String[stringArray.size()];
        return stringArray.toArray(stockArr);
    }
}

Main.java

package org.gnusosa;

import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.geometry.Insets;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.Label;
import javafx.scene.control.TextArea;
import javafx.scene.control.TextField;
import javafx.scene.layout.GridPane;
import javafx.scene.layout.HBox;
import javafx.scene.paint.Color;
import javafx.scene.text.Font;
import javafx.scene.text.FontWeight;
import javafx.scene.text.Text;
import javafx.stage.Stage;
import javafx.scene.control.Button;

import java.io.FileNotFoundException;
import java.util.HashSet;


public class Main extends Application {

    @Override
    public void start(Stage primaryStage) throws Exception {
        GridPane grid = new GridPane();
        grid.setAlignment(Pos.CENTER);
        grid.setHgap(10);
        grid.setVgap(10);
        grid.setPadding(new Insets(0, 0, 0, 0));

        Scene scene = new Scene(grid, 800, 600);

        Text scenetitle = new Text("Read Text File");
        scenetitle.setFont(Font.font("Tahoma", FontWeight.NORMAL, 20));
        grid.add(scenetitle, 0, 0, 2, 1);

        TextArea userTextArea = new TextArea();
        grid.add(userTextArea, 1, 1);

        TextField userTextField = new TextField();
        grid.add(userTextField, 1, 4);

        Button btn = new Button("Read File to TextArea");
        HBox hbBtn = new HBox(10);
        hbBtn.setAlignment(Pos.BOTTOM_RIGHT);
        hbBtn.getChildren().add(btn);
        grid.add(hbBtn, 0, 4);

        final Text actionTarget = new Text();
        grid.add(actionTarget, 1, 6);

        btn.setOnAction(new EventHandler<ActionEvent>() {

            @Override
            public void handle(ActionEvent e) {
                String filePath = userTextField.getText();
                try {
                    ReadText readText = new ReadText(filePath);
                    userTextArea.setWrapText(false);
                    userTextArea.setText(readText.getAll());
                } catch (FileNotFoundException err) {
                    actionTarget.setFill(Color.FIREBRICK);
                    actionTarget.setText("Couldn't open the file. Error: " + err.toString());
                }
            }
        });

        primaryStage.setScene(scene);
        primaryStage.setTitle("Read a text file");

        primaryStage.show();

    }


    public static void main(String[] args) {
        launch(args);
    }
}

ReadText.java

package org.gnusosa;


import java.io.FileNotFoundException;
import java.util.ArrayList;
import java.util.Scanner;

public class ReadText extends FileManager {
    private Scanner scanner;

    public Scanner getScanner() {
        return scanner;
    }


    public ReadText(Scanner scanner) {
        this.scanner = scanner;
    }

    public ReadText(String path) throws FileNotFoundException {
        super(path);
        this.scanner = new Scanner(this.getFileHandler());

    }

    @Override
    public String getLine(int lineNumber) {
        String[] stringArray = this.getArrayOfLines();
        this.getScanner().reset();
        return stringArray[lineNumber];
    }

    @Override
    public String getAll() {
        StringBuffer sbuffer = new StringBuffer();
        while(this.getScanner().hasNext()) {
            sbuffer.append(this.getScanner().nextLine() + "\n");
        }

        this.getScanner().reset();
        return sbuffer.toString();
    }

    @Override
    public String[] getArrayOfLines() {
        ArrayList<String> stringArray = new ArrayList<String>();
        while(this.getScanner().hasNextLine()) {
            stringArray.add(this.getScanner().nextLine());
        }

        this.getScanner().reset();

        String[] stockArr = new String[stringArray.size()];
        return stringArray.toArray(stockArr);
    }
}