TextCanvas.java

import javafx.application.Application;
import static javafx.application.Application.launch;
import javafx.geometry.VPos;
import javafx.scene.*;
import javafx.scene.canvas.*;
import javafx.scene.layout.StackPane;
import javafx.scene.text.TextAlignment;
import javafx.stage.Stage;
import javafx.scene.text.*;

public class TextCanvas extends Application {
    @Override public void start(Stage primaryStage) {
        Canvas canvas = new Canvas(175, 40);
        GraphicsContext gc = canvas.getGraphicsContext2D();
        gc.setTextAlign(TextAlignment.CENTER);
        gc.setTextBaseline(VPos.CENTER);
	double width = canvas.getWidth();
	double height = canvas.getHeight();
	String str;
	str= String.format("Canvas size %d x %d",(int) width, (int) height);
        gc.fillText(
            str, 
            Math.round( width / 2), 
            Math.round(height / 2)
        );

        StackPane layout = new StackPane();
        layout.getChildren().addAll(canvas);

	Text text = new Text(10,10,str);
	width = text.getLayoutBounds().getWidth();
	height = text.getLayoutBounds().getHeight();
	System.out.format("String width: %d\n",(int)width);


        primaryStage.setScene(new Scene(layout));
        primaryStage.show();
    }
    public static void main(String[] args) { launch(args); }
}