"java.lang.RuntimeException: java.lang.reflect.InvocationTargetException" - unable to figure out where the error is coming from

Question

Getting an error when trying to click the "Add" button in the Parts section of the mainwindow.fxml

Here's the error:

/Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/bin/java -javaagent:/Applications/IntelliJ IDEA.app/Contents/lib/idea_rt.jar=51593:/Applications/IntelliJ IDEA.app/Contents/bin -Dfile.encoding=UTF-8 -classpath /Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/jre/lib/charsets.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/jre/lib/deploy.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/jre/lib/ext/cldrdata.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/jre/lib/ext/dnsns.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/jre/lib/ext/jaccess.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/jre/lib/ext/jfxrt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/jre/lib/ext/localedata.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/jre/lib/ext/nashorn.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/jre/lib/ext/sunec.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/jre/lib/ext/sunjce_provider.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/jre/lib/ext/sunpkcs11.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/jre/lib/ext/zipfs.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/jre/lib/javaws.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/jre/lib/jce.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/jre/lib/jfr.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/jre/lib/jfxswt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/jre/lib/jsse.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/jre/lib/management-agent.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/jre/lib/plugin.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/jre/lib/resources.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/jre/lib/rt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/lib/ant-javafx.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/lib/dt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/lib/javafx-mx.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/lib/jconsole.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/lib/packager.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/lib/sa-jdi.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/lib/tools.jar:/Users/wes/Dropbox/wes-WGU/software-i-c482/javafx/inventory-system-c482-wesley-oneal-2/out/production/InventorySystem-C482-wesley-oneal-2 wesleyoneal.inventoryapp.Main
Exception in thread "JavaFX Application Thread" java.lang.RuntimeException: java.lang.reflect.InvocationTargetException
    at javafx.fxml.FXMLLoader$MethodHandler.invoke(FXMLLoader.java:1774)
    at javafx.fxml.FXMLLoader$ControllerMethodEventHandler.handle(FXMLLoader.java:1657)
    at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:86)
    at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:238)
    at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191)
    at com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(CompositeEventDispatcher.java:59)
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:58)
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
    at com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:74)
    at com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:49)
    at javafx.event.Event.fireEvent(Event.java:198)
    at javafx.scene.Node.fireEvent(Node.java:8411)
    at javafx.scene.control.Button.fire(Button.java:185)
    at com.sun.javafx.scene.control.behavior.ButtonBehavior.mouseReleased(ButtonBehavior.java:182)
    at com.sun.javafx.scene.control.skin.BehaviorSkinBase$1.handle(BehaviorSkinBase.java:96)
    at com.sun.javafx.scene.control.skin.BehaviorSkinBase$1.handle(BehaviorSkinBase.java:89)
    at com.sun.javafx.event.CompositeEventHandler$NormalEventHandlerRecord.handleBubblingEvent(CompositeEventHandler.java:218)
    at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:80)
    at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:238)
    at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191)
    at com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(CompositeEventDispatcher.java:59)
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:58)
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
    at com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:74)
    at com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:54)
    at javafx.event.Event.fireEvent(Event.java:198)
    at javafx.scene.Scene$MouseHandler.process(Scene.java:3757)
    at javafx.scene.Scene$MouseHandler.access$1500(Scene.java:3485)
    at javafx.scene.Scene.impl_processMouseEvent(Scene.java:1762)
    at javafx.scene.Scene$ScenePeerListener.mouseEvent(Scene.java:2494)
    at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:394)
    at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:295)
    at java.security.AccessController.doPrivileged(Native Method)
    at com.sun.javafx.tk.quantum.GlassViewEventHandler.lambda$handleMouseEvent$2(GlassViewEventHandler.java:432)
    at com.sun.javafx.tk.quantum.QuantumToolkit.runWithoutRenderLock(QuantumToolkit.java:410)
    at com.sun.javafx.tk.quantum.GlassViewEventHandler.handleMouseEvent(GlassViewEventHandler.java:431)
    at com.sun.glass.ui.View.handleMouseEvent(View.java:555)
    at com.sun.glass.ui.View.notifyMouse(View.java:937)
Caused by: java.lang.reflect.InvocationTargetException
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at sun.reflect.misc.Trampoline.invoke(MethodUtil.java:71)
    at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at sun.reflect.misc.MethodUtil.invoke(MethodUtil.java:275)
    at javafx.fxml.FXMLLoader$MethodHandler.invoke(FXMLLoader.java:1769)
    ... 49 more
Caused by: javafx.fxml.LoadException: 
/Users/wes/Dropbox/wes-WGU/software-i-c482/javafx/inventory-system-c482-wesley-oneal-2/out/production/InventorySystem-C482-wesley-oneal-2/wesleyoneal/inventoryapp/addpart.fxml:18

    at javafx.fxml.FXMLLoader.constructLoadException(FXMLLoader.java:2601)
    at javafx.fxml.FXMLLoader.access$700(FXMLLoader.java:103)
    at javafx.fxml.FXMLLoader$ValueElement.processAttribute(FXMLLoader.java:932)
    at javafx.fxml.FXMLLoader$InstanceDeclarationElement.processAttribute(FXMLLoader.java:971)
    at javafx.fxml.FXMLLoader$Element.processStartElement(FXMLLoader.java:220)
    at javafx.fxml.FXMLLoader$ValueElement.processStartElement(FXMLLoader.java:744)
    at javafx.fxml.FXMLLoader.processStartElement(FXMLLoader.java:2707)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2527)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2441)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3214)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3175)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3148)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3124)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3104)
    at javafx.fxml.FXMLLoader.load(FXMLLoader.java:3097)
    at wesleyoneal.inventoryapp.mainController.addPartWindow(mainController.java:59)
    ... 59 more
Caused by: java.lang.InstantiationException: wesleyoneal.inventoryapp.Part
    at java.lang.Class.newInstance(Class.java:427)
    at sun.reflect.misc.ReflectUtil.newInstance(ReflectUtil.java:51)
    at javafx.fxml.FXMLLoader$ValueElement.processAttribute(FXMLLoader.java:927)
    ... 72 more
Caused by: java.lang.NoSuchMethodException: wesleyoneal.inventoryapp.Part.<init>()
    at java.lang.Class.getConstructor0(Class.java:3082)
    at java.lang.Class.newInstance(Class.java:412)
    ... 74 more

Process finished with exit code 0

I've looked at line 18 in the addpart.fxml where it says it's having issues, but everything there looks correct from what I can tell

Main.java:

package wesleyoneal.inventoryapp;

import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.stage.Stage;

public class Main extends Application {

    @Override
    public void start(Stage primaryStage) throws Exception {
        Parent root = FXMLLoader.load(getClass().getResource("mainwindow.fxml"));
        primaryStage.setScene(new Scene(root, 1180, 472));
        primaryStage.show();
    }

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

mainController:

package wesleyoneal.inventoryapp;

import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.event.ActionEvent;
import javafx.fxml.FXML;
import javafx.fxml.FXMLLoader;
import javafx.fxml.Initializable;
import javafx.scene.Node;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableView;
import javafx.scene.control.cell.PropertyValueFactory;
import javafx.stage.Stage;

import java.io.IOException;
import java.net.URL;
import java.util.ResourceBundle;

public class mainController implements Initializable {

    @FXML
    private TableView<Part> partsTable;
    @FXML
    private TableColumn<Part, Integer> partIdColumn;
    @FXML
    private TableColumn<Part, String> partNameColumn;
    @FXML
    private TableColumn<Part, Integer> partInvLevel;
    @FXML
    private TableColumn<Part, Double> partPriceCostColumn;

    @Override
    public void initialize(URL location, ResourceBundle resources) {
        partIdColumn.setCellValueFactory(new PropertyValueFactory<>("id"));
        partNameColumn.setCellValueFactory(new PropertyValueFactory<>("name"));
        partInvLevel.setCellValueFactory(new PropertyValueFactory<>("stock"));
        partPriceCostColumn.setCellValueFactory(new PropertyValueFactory<>("price"));

        partsTable.setItems(getParts());
    }

    public ObservableList<Part> getParts() {
        ObservableList<Part> partsList = FXCollections.observableArrayList();
        partsList.add(new InHousePart(1, "Part A", 1.99, 11, 1, 21, 1111));
        partsList.add(new InHousePart(2, "Part B", 2.99, 12, 2, 22, 2222));
        partsList.add(new OutsourcedPart(3, "Part C", 3.99, 13, 3, 33,
                "Wes' Company"));
        partsList.add(new OutsourcedPart(4, "Part D", 4.99, 14, 4, 44,
                "Wes' Company"));

        return partsList;

    }

    @FXML
    private void addPartWindow(ActionEvent event) throws IOException {
        Parent addPartParent = FXMLLoader.load(getClass().getResource("addpart.fxml"));
        Scene addPartScene = new Scene(addPartParent);
        Stage addPartStage = (Stage) ((Node) event.getSource()).getScene().getWindow();
        addPartStage.setScene(addPartScene);
        addPartStage.show();
    }
}

mainwindow.fxml:

<?xml version="1.0" encoding="UTF-8"?>

<?import javafx.geometry.Insets?>
<?import javafx.scene.control.Button?>
<?import javafx.scene.control.ButtonBar?>
<?import javafx.scene.control.Label?>
<?import javafx.scene.control.TableColumn?>
<?import javafx.scene.control.TableView?>
<?import javafx.scene.control.TextField?>
<?import javafx.scene.layout.ColumnConstraints?>
<?import javafx.scene.layout.GridPane?>
<?import javafx.scene.layout.RowConstraints?>
<?import javafx.scene.shape.Rectangle?>
<?import javafx.scene.text.Font?>
<?import javafx.scene.text.Text?>

<GridPane fx:id="mainGridPane" alignment="center" hgap="10" style="-fx-background-color: lightgrey;" vgap="10.0" xmlns="http://javafx.com/javafx/8.0.171" xmlns:fx="http://javafx.com/fxml/1" fx:controller="wesleyoneal.inventoryapp.mainController">
    <columnConstraints>
        <ColumnConstraints />
        <ColumnConstraints maxWidth="600.0" minWidth="560.0" prefWidth="600.0" />
        <ColumnConstraints maxWidth="0.0" minWidth="0.0" prefWidth="0.0" />
    </columnConstraints>
    <rowConstraints>
        <RowConstraints />
        <RowConstraints />
        <RowConstraints />
        <RowConstraints />
        <RowConstraints />
        <RowConstraints />
        <RowConstraints maxHeight="0.0" minHeight="0.0" prefHeight="0.0" />
        <RowConstraints maxHeight="0.0" minHeight="0.0" prefHeight="0.0" />
    </rowConstraints>
    <children>
        <Label text="Inventory Management System" textFill="#494980">
            <font>
                <Font name="Helvetica Bold" size="16.0" />
            </font>
            <GridPane.margin>
                <Insets bottom="30.0" left="40.0" top="30.0" />
            </GridPane.margin>
        </Label>
        <Rectangle arcHeight="15.0" arcWidth="15.0" fill="#1f93ff00" height="260.0" stroke="#949494" strokeType="INSIDE" width="520.0" GridPane.rowIndex="1" GridPane.rowSpan="3">
            <GridPane.margin>
                <Insets left="40.0" />
            </GridPane.margin>
        </Rectangle>
        <TableView fx:id="partsTable" maxWidth="480.0" prefHeight="140.0" prefWidth="480.0" GridPane.rowIndex="2">
            <columns>
                <TableColumn fx:id="partIdColumn" maxWidth="120.0" prefWidth="120.0" text="Part ID" />
                <TableColumn fx:id="partNameColumn" maxWidth="120.0" prefWidth="120.0" text="Part Name" />
                <TableColumn fx:id="partInvLevel" maxWidth="120.0" prefWidth="120.0" text="Inventory Level" />
                <TableColumn fx:id="partPriceCostColumn" maxWidth="120.0" prefWidth="120.0" text="Price/Cost per Unit" />
            </columns>
            <GridPane.margin>
                <Insets left="60.0" />
            </GridPane.margin>
        </TableView>
        <ButtonBar maxWidth="480.0" prefHeight="40.0" prefWidth="250.0" GridPane.rowIndex="3">
            <buttons>
                <Button mnemonicParsing="false" onAction="#addPartWindow" text="Add" />
                <Button mnemonicParsing="false" text="Modify" />
                <Button mnemonicParsing="false" text="Delete" />
            </buttons>
            <GridPane.margin>
                <Insets bottom="10.0" left="30.0" />
            </GridPane.margin>
        </ButtonBar>
        <Text strokeType="OUTSIDE" strokeWidth="0.0" text="Parts" GridPane.rowIndex="1">
            <GridPane.margin>
                <Insets bottom="10.0" left="70.0" top="20.0" />
            </GridPane.margin>
            <font>
                <Font name="Helvetica Bold" size="16.0" />
            </font>
        </Text>
        <Button mnemonicParsing="false" text="Search" GridPane.rowIndex="1">
            <GridPane.margin>
                <Insets left="260.0" top="10.0" />
            </GridPane.margin>
        </Button>
        <TextField maxWidth="200.0" GridPane.rowIndex="1">
            <GridPane.margin>
                <Insets left="340.0" top="11.0" />
            </GridPane.margin>
        </TextField>
        <Rectangle arcHeight="15.0" arcWidth="15.0" fill="#1f93ff00" height="260.0" stroke="#949494" strokeType="INSIDE" width="520.0" GridPane.columnIndex="1" GridPane.rowIndex="1" GridPane.rowSpan="3">
            <GridPane.margin>
                <Insets left="40.0" />
            </GridPane.margin>
        </Rectangle>
        <TableView fx:id="productsTable" maxWidth="480.0" prefHeight="140.0" prefWidth="480.0" GridPane.columnIndex="1" GridPane.rowIndex="2">
            <columns>
                <TableColumn prefWidth="120.0" text="Part ID" />
                <TableColumn prefWidth="120.0" text="Part Name" />
                <TableColumn prefWidth="120.0" text="Inventory Level" />
                <TableColumn prefWidth="120.0" text="Price per Unit" />
            </columns>
            <GridPane.margin>
                <Insets left="60.0" />
            </GridPane.margin>
        </TableView>
        <ButtonBar maxWidth="480.0" prefHeight="40.0" prefWidth="250.0" GridPane.columnIndex="1" GridPane.rowIndex="3">
            <buttons>
                <Button mnemonicParsing="false" text="Add" />
                <Button mnemonicParsing="false" text="Modify" />
                <Button mnemonicParsing="false" text="Delete" />
            </buttons>
            <GridPane.margin>
                <Insets bottom="10.0" left="30.0" />
            </GridPane.margin>
        </ButtonBar>
        <Button mnemonicParsing="false" text="Search" GridPane.columnIndex="1" GridPane.rowIndex="1">
            <GridPane.margin>
                <Insets left="260.0" top="10.0" />
            </GridPane.margin>
        </Button>
        <TextField maxWidth="200.0" GridPane.columnIndex="1" GridPane.rowIndex="1">
            <GridPane.margin>
                <Insets left="340.0" top="11.0" />
            </GridPane.margin>
        </TextField>
        <Button mnemonicParsing="false" text="Exit" GridPane.columnIndex="1" GridPane.halignment="RIGHT" GridPane.rowIndex="4">
            <GridPane.margin>
                <Insets right="60.0" top="10.0" />
            </GridPane.margin>
        </Button>
        <Text strokeType="OUTSIDE" strokeWidth="0.0" text="Products" GridPane.columnIndex="1" GridPane.rowIndex="1">
            <font>
                <Font name="Helvetica Bold" size="16.0" />
            </font>
            <GridPane.margin>
                <Insets bottom="10.0" left="70.0" top="20.0" />
            </GridPane.margin>
        </Text>
    </children>
</GridPane>

addpart.fxml:

<?xml version="1.0" encoding="UTF-8"?>

<?import javafx.geometry.Insets?>
<?import javafx.scene.Group?>
<?import javafx.scene.control.Button?>
<?import javafx.scene.control.ButtonBar?>
<?import javafx.scene.control.Label?>
<?import javafx.scene.control.RadioButton?>
<?import javafx.scene.control.TextField?>
<?import javafx.scene.control.ToggleGroup?>
<?import javafx.scene.layout.ColumnConstraints?>
<?import javafx.scene.layout.GridPane?>
<?import javafx.scene.layout.RowConstraints?>
<?import javafx.scene.text.Font?>
<?import javafx.scene.text.Text?>

<GridPane fx:id="partGrid" style="-fx-background-color: lightgrey;" xmlns="http://javafx.com/javafx/8.0.171"
          xmlns:fx="http://javafx.com/fxml/1" fx:controller="wesleyoneal.inventoryapp.Part">
    <columnConstraints>
        <ColumnConstraints/>
        <ColumnConstraints/>
        <ColumnConstraints/>
    </columnConstraints>
    <rowConstraints>
        <RowConstraints/>
        <RowConstraints prefHeight="60.0"/>
        <RowConstraints prefHeight="60.0"/>
        <RowConstraints prefHeight="60.0"/>
        <RowConstraints minHeight="10.0" prefHeight="60.0"/>
        <RowConstraints minHeight="10.0" prefHeight="60.0"/>
        <RowConstraints minHeight="10.0" prefHeight="60.0"/>
        <RowConstraints minHeight="10.0"/>
    </rowConstraints>
    <children>
        <Label text="Add Part" textFill="#494980">
            <font>
                <Font name="Helvetica Bold" size="16.0"/>
            </font>
            <GridPane.margin>
                <Insets bottom="30.0" left="40.0" top="30.0"/>
            </GridPane.margin>
        </Label>
        <Text id="partIdLabel" strokeType="OUTSIDE" strokeWidth="0.0" text="ID" GridPane.rowIndex="1">
            <GridPane.margin>
                <Insets bottom="10.0" left="80.0" top="10.0"/>
            </GridPane.margin>
        </Text>
        <Text id="partNameLabel" strokeType="OUTSIDE" strokeWidth="0.0" text="Name" GridPane.rowIndex="2">
            <GridPane.margin>
                <Insets bottom="10.0" left="80.0" top="10.0"/>
            </GridPane.margin>
        </Text>
        <Text id="partInvLabel" strokeType="OUTSIDE" strokeWidth="0.0" text="Inv" GridPane.rowIndex="3">
            <GridPane.margin>
                <Insets bottom="10.0" left="80.0" top="10.0"/>
            </GridPane.margin>
        </Text>
        <Text id="partPriceCostLabel" strokeType="OUTSIDE" strokeWidth="0.0" text="Price/Cost" GridPane.rowIndex="4">
            <GridPane.margin>
                <Insets bottom="10.0" left="80.0" top="10.0"/>
            </GridPane.margin>
        </Text>
        <Text id="partMaxLabel" strokeType="OUTSIDE" strokeWidth="0.0" text="Max" GridPane.rowIndex="5">
            <GridPane.margin>
                <Insets bottom="10.0" left="80.0" top="10.0"/>
            </GridPane.margin>
        </Text>
        <Text id="partMinLabel" strokeType="OUTSIDE" strokeWidth="0.0" text="Min" GridPane.columnIndex="1"
              GridPane.columnSpan="2" GridPane.rowIndex="5">
            <GridPane.margin>
                <Insets left="180.0"/>
            </GridPane.margin>
        </Text>
        <Text id="partCompanyNameLabel" strokeType="OUTSIDE" strokeWidth="0.0" text="Company Name"
              GridPane.rowIndex="6">
            <GridPane.margin>
                <Insets bottom="10.0" left="80.0" top="10.0"/>
            </GridPane.margin>
        </Text>
        <Text id="partMachineIdLabel" strokeType="OUTSIDE" strokeWidth="0.0" text="Machine ID" GridPane.rowIndex="6">
            <GridPane.margin>
                <Insets bottom="10.0" left="80.0" top="10.0"/>
            </GridPane.margin>
        </Text>
        <ButtonBar prefHeight="40.0" prefWidth="200.0" GridPane.columnIndex="2" GridPane.halignment="RIGHT"
                   GridPane.rowIndex="7">
            <buttons>
                <Button mnemonicParsing="false" text="Save"/>
                <Button mnemonicParsing="false" text="Cancel"/>
            </buttons>
            <GridPane.margin>
                <Insets bottom="20.0" right="30.0"/>
            </GridPane.margin>
        </ButtonBar>
        <Group GridPane.columnIndex="1" GridPane.columnSpan="2">
            <children>
                <RadioButton fx:id="partInHouseButton" mnemonicParsing="false"
                             prefWidth="100.0" selected="true" text="In-House">
                    <toggleGroup>
                        <ToggleGroup fx:id="addPartToggleGroup"/>
                    </toggleGroup>
                </RadioButton>
                <RadioButton fx:id="partOutsourcedButton" layoutX="183.0" mnemonicParsing="false"
                             prefWidth="100.0" text="Outsourced"
                             toggleGroup="$addPartToggleGroup"/>
            </children>
        </Group>
        <TextField id="partIdField" editable="false" prefHeight="40.0"
                   style="-fx-background-color: lightgrey; -fx-border-color: grey;" text="Auto Gen - Disabled"
                   GridPane.columnIndex="1" GridPane.rowIndex="1">
            <GridPane.margin>
                <Insets left="20.0"/>
            </GridPane.margin>
        </TextField>
        <TextField id="partNameField" prefHeight="40.0" GridPane.columnIndex="1" GridPane.rowIndex="2">
            <GridPane.margin>
                <Insets left="20.0"/>
            </GridPane.margin>
        </TextField>
        <TextField id="partInvField" prefHeight="40.0" GridPane.columnIndex="1" GridPane.rowIndex="3">
            <GridPane.margin>
                <Insets left="20.0"/>
            </GridPane.margin>
        </TextField>
        <TextField id="partPriceCostField" prefHeight="40.0" GridPane.columnIndex="1" GridPane.rowIndex="4">
            <GridPane.margin>
                <Insets left="20.0"/>
            </GridPane.margin>
        </TextField>
        <TextField id="partMaxField" maxWidth="120.0" prefHeight="40.0" GridPane.columnIndex="1" GridPane.rowIndex="5">
            <GridPane.margin>
                <Insets left="20.0"/>
            </GridPane.margin>
        </TextField>
        <TextField id="partMinField" maxWidth="120.0" prefHeight="40.0" GridPane.columnIndex="2" GridPane.rowIndex="5">
            <GridPane.margin>
                <Insets left="40.0" right="40.0"/>
            </GridPane.margin>
        </TextField>
        <TextField id="partCompanyNameField" prefHeight="40.0" GridPane.columnIndex="1" GridPane.rowIndex="6">
            <GridPane.margin>
                <Insets left="20.0"/>
            </GridPane.margin>
        </TextField>
        <TextField id="partMachineIdField" prefHeight="40.0" GridPane.columnIndex="1" GridPane.rowIndex="6">
            <GridPane.margin>
                <Insets left="20.0"/>
            </GridPane.margin>
        </TextField>
    </children>
</GridPane>

Part.java:

package wesleyoneal.inventoryapp;

public abstract class Part {
    private int id;
    private String name;
    private double price;
    private int stock;
    private int min;
    private int max;

    public Part(int id, String name, double price, int stock, int min, int max) {
        this.id = id;
        this.name = name;
        this.price = price;
        this.stock = stock;
        this.min = min;
        this.max = max;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public double getPrice() {
        return price;
    }

    public void setPrice(double price) {
        this.price = price;
    }

    public int getStock() {
        return stock;
    }

    public void setStock(int stock) {
        this.stock = stock;
    }

    public int getMin() {
        return min;
    }

    public void setMin(int min) {
        this.min = min;
    }

    public int getMax() {
        return max;
    }

    public void setMax(int max) {
        this.max = max;
    }
}

InHousePart.java:

package wesleyoneal.inventoryapp;

public class InHousePart extends Part {

    private int machineId;

    public InHousePart(int id, String name, double price, int stock, int min, int max, int machineId) {
        super(id, name, price, stock, min, max);
        this.machineId = machineId;
    }

    public int getMachineId() {
        return machineId;
    }

    public void setMachineId(int machineId) {
        this.machineId = machineId;
    }
}

Outsourcedpart.java:

package wesleyoneal.inventoryapp;

public class OutsourcedPart extends Part {

    private String companyName;

    public OutsourcedPart(int id, String name, double price, int stock, int min, int max, String companyName) {
        super(id, name, price, stock, min, max);
        this.companyName = companyName;
    }

    public String getCompanyName() {
        return companyName;
    }

    public void setCompanyName(String companyName) {
        this.companyName = companyName;
    }
}