In Murach Java $6$th Edition

FutureValueApplication.java

import java.text.NumberFormat;

import javafx.application.Application;

import javafx.geometry.Insets;

import javafx.geometry.Pos;

import javafx.scene.Scene;

import javafx.scene.control.Alert;

import javafx.scene.control.Button;

import javafx.scene.control.Label;

import javafx.scene.control.TextField;

import javafx.scene.layout.GridPane;

import javafx.scene.layout.HBox;

import javafx.stage.Stage;

public class FutureValueApplication extends Application $\{$

private TextField investmentField;

private TextField interestRateField;

private TextField yearsField;

private TextField futureValueField;

public static void main$($String$[]$ args$)\{$

launch$($args$)$;

$\}$

@Override

public void start$($Stage primaryStage$)\{$

primaryStage.setTitle$("$Future Value Calculator"$)$;

GridPane grid $=$ new GridPane$()$;

grid.setAlignment$($Pos$.$TOP$\_$CENTER$)$;

grid.setPadding$($new Insets$(25,25,25,25))$;

grid.setHgap$(10)$;

grid.setVgap$(10)$;

Scene scene $=$ new Scene$($grid$)$;

grid.add$($new Label$("$Monthly Investment:"$),0,0)$;

investmentField $=$ new TextField$()$;

grid.add$($investmentField$,1,0)$;

grid.add$($new Label$("$Yearly Interest Rate:"$),0,1)$;

interestRateField $=$ new TextField$()$;

grid.add$($interestRateField$,1,1)$;

grid.add$($new Label$("$Years:$"),0,2)$;

yearsField $=$ new TextField$()$;

grid.add$($yearsField$,1,2)$;

grid.add$($new Label$("$Future Value:"$),0,3)$;

futureValueField $=$ new TextField$()$;

futureValueField.setEditable$($false$)$;

grid.add$($futureValueField$,1,3)$;

Button calculateButton $=$ new Button$("$Calculate$")$;

calculateButton.setOnAction$($event $->$ calculateButtonClicked$())$;

Button exitButton $=$ new Button$("$Exit$")$;

exitButton.setOnAction$($event $->$ exitButtonClicked$())$;

HBox buttonBox $=$ new HBox$(10)$;

buttonBox.getChildren$().$add$($calculateButton$)$;

buttonBox.getChildren$().$add$($exitButton$)$;

buttonBox.setAlignment$($Pos$.$BOTTOM$\_$RIGHT$)$;

grid.add$($buttonBox$,0,4,2,1)$;

primaryStage.setScene$($scene$)$;

primaryStage.show$()$;

$\}$

private void calculateButtonClicked$()\{$

Validation v $=$ new Validation$()$;

String errorMsg $=""$;

errorMsg $+=$ v$.$isDouble$($investmentField$.$getText$(),$

"Monthly Investment"$)$;

errorMsg $+=$ v$.$isDouble$($interestRateField$.$getText$(),$

"Yearly Interest Rate"$)$;

errorMsg $+=$ v$.$isInteger$($yearsField$.$getText$(),$

"Years"$)$;

if $($errorMsg$.$isEmpty$())\{$

double investment $=$ Double.parseDouble$($

investmentField.getText$())$;

double rate $=$ Double.parseDouble$($

interestRateField.getText$())$;

int years $=$ Integer.parseInt$($

yearsField.getText$())$;

double futureValue $=$ calculateFutureValue$($

investment, rate, years$)$;

NumberFormat currency $=$ NumberFormat.getCurrencyInstance$()$;

futureValueField.setText$($currency$.$format$($futureValue$))$;

$\}$ else $\{$

Alert alert $=$ new Alert$($Alert$.$AlertType.ERROR$)$;

alert.setHeaderText$("$Invalid Data"$)$;

alert.setContentText$($errorMsg$)$;

alert.showAndWait$()$;

$\}$

$\}$

public double calculateFutureValue$($double investment, double rate, int years$)\{$

double futureValue $=0\mathrm{.}0$;

$//$ convert yearly values to monthly values

double monthlyInterestRate $=$ rate $/12/100$;

int months $=$ years $*12$;

for $($int i $=1$; i months; i$++)\{$

futureValue $=($futureValue $+$ investment$)$

$*(1+$ monthlyInterestRate$)$;

$\}$

return futureValue;

$\}$

private void exitButtonClicked$()\{$

System.exit$(0)$; $//0$ indicates a normal exit

$\}$

$\}$

Validation.java:

$//$package com.murach.future$\_$value;

public class Validation $\{$

private final String lineEnd;

public Validation$()\{$

this.lineEnd $="$

$"$;

$\}$

public Validation$($String lineEnd$)\{$

this.lineEnd $=$ lineEnd;

$\}$

public String isPresent$($String value, String name$)\{$

String msg $=""$;

if $($value$.$isEmpty$())\{$

msg $=$ name $+"$ is required." $+$ lineEnd;

$\}$

return msg;

$\}$

public String isDouble$($String value, String name$)\{$

String msg $=""$;

try $\{$

Double.parseDouble$($value$)$;

$\}$ catch $($NumberFormatException e$)\{$

msg $=$ name $+"$ must be a valid number." $+$ lineEnd;

$\}$

return msg;

$\}$

public String isInteger$($String value, String name$)\{$

String msg $=""$;

try $\{$

Integer.parseInt$($value$)$;

$\}$ catch $($NumberFormatException e$)\{$

msg $=$ name $+"$ must be an integer." $+$ lineEnd;

$\}$

return msg;

$\}$

$\}$