Database '；应用程序启动方法java.lang.reflect.InvocationTargetException'中出现异常；从数据库中读取和显示时
我试图从MySQL数据库中读取值，并将其显示在JavaFX中的表中。我使用netbeanside。当我运行代码时，我得到了标题中提到的异常。我将在下面发布代码：Database '；应用程序启动方法java.lang.reflect.InvocationTargetException'中出现异常；从数据库中读取和显示时,database,exception,javafx,javafx-2,Database,Exception,Javafx,Javafx 2,我试图从MySQL数据库中读取值，并将其显示在JavaFX中的表中。我使用netbeanside。当我运行代码时，我得到了标题中提到的异常。我将在下面发布代码： public class ViewSubject extends Application { private final TableView<Subject> table = new TableView<>(); private final ObservableList<Subject> data
public class ViewSubject extends Application {
private final TableView<Subject> table = new TableView<>();
private final ObservableList<Subject> data
= FXCollections.observableArrayList();
final HBox hb = new HBox();
private Connection connect = null;
private Statement statement = null;
private final PreparedStatement preparedStatement = null;
private ResultSet resultSet = null;
public static void main(String[] args) {
launch(args);
}
@Override
public void start(Stage stage) throws ClassNotFoundException, SQLException {
Scene scene = new Scene(new Group());
stage.setTitle("Add Subject");
stage.setWidth(650);
stage.setHeight(550);
stage.setResizable(false);
final Label label = new Label("Subject Details");
label.setFont(new Font("Calibri", 20));
TableColumn sub = new TableColumn("Subject Name");
sub.setMinWidth(350);
sub.setCellValueFactory(
new PropertyValueFactory<Subject, String>("subName"));
sub.setCellFactory(TextFieldTableCell.forTableColumn());
sub.setOnEditCommit(
new EventHandler<TableColumn.CellEditEvent<Subject, String>>() {
@Override
public void handle(TableColumn.CellEditEvent<Subject, String> t) {
((Subject) t.getTableView().getItems().get(
t.getTablePosition().getRow())).setSubName(t.getNewValue());
}
}
);
TableColumn code = new TableColumn("Subject Code");
code.setMinWidth(130);
code.setCellValueFactory(
new PropertyValueFactory<Subject, String>("subCode"));
code.setCellFactory(TextFieldTableCell.forTableColumn());
code.setCellFactory(TextFieldTableCell.forTableColumn());
code.setOnEditCommit(
new EventHandler<TableColumn.CellEditEvent<Subject, String>>() {
@Override
public void handle(TableColumn.CellEditEvent<Subject, String> t) {
((Subject) t.getTableView().getItems().get(
t.getTablePosition().getRow())).setSubCode(t.getNewValue());
}
}
);
TableColumn rev = new TableColumn("Revision");
rev.setMinWidth(130);
rev.setCellValueFactory(
new PropertyValueFactory<Subject, String>("subRev"));
rev.setCellFactory(TextFieldTableCell.forTableColumn());
rev.setCellFactory(TextFieldTableCell.forTableColumn());
rev.setOnEditCommit(
new EventHandler<TableColumn.CellEditEvent<Subject, String>>() {
@Override
public void handle(TableColumn.CellEditEvent<Subject, String> t) {
((Subject) t.getTableView().getItems().get(
t.getTablePosition().getRow())).setSubCode(t.getNewValue());
}
}
);
table.setItems(data);
table.getColumns().addAll(sub, code, rev);
final VBox vbox = new VBox();
vbox.setSpacing(10);
vbox.setPadding(new Insets(20, 20, 20, 20));
vbox.getChildren().addAll(label, table);
((Group) scene.getRoot()).getChildren().addAll(vbox);
stage.setScene(scene);
stage.show();
try {
Class.forName("com.mysql.jdbc.Driver");
connect = DriverManager
.getConnection("jdbc:mysql://localhost:3306/project?"
+ "user=root&password=virus");
statement = connect.createStatement();
resultSet = statement
.executeQuery("select * from subject");
writeResultSet(resultSet);
} catch (ClassNotFoundException | SQLException e) {
throw e;
} finally {
close();
}
}
private void writeResultSet(ResultSet resultSet) throws SQLException {
while (resultSet.next()) {
String subname = resultSet.getString("subname");
String code = resultSet.getString("subcode");
String rev = resultSet.getString("subrev");
data.add(new Subject(subname, code, rev));
}
}
private void close() {
try {
if (resultSet != null) {
resultSet.close();
}
if (statement != null) {
statement.close();
}
if (connect != null) {
connect.close();
}
} catch (SQLException e) {
}
}
}
发布代码时，请尝试发布与堆栈跟踪匹配的代码。StackTrace在viewsubject.viewsubject.read（viewsubject.java:119）报告了一个错误，但是在viewsubject类中没有这样的read函数。您是如何理解这个问题的，意思是您是如何发现我的类路径中没有MySQL JDBC驱动程序的？
public class Subject {
private final SimpleStringProperty sub;
private final SimpleStringProperty code;
private final SimpleStringProperty rev;
Subject(String subName, String subCode, String subRev) {
this.sub = new SimpleStringProperty(subName);
this.code = new SimpleStringProperty(subCode);
this.rev = new SimpleStringProperty(subRev);
}
public String getSubName() {
return sub.get();
}
public void setSubName(String subName) {
sub.set(subName);
}
public String getSubCode() {
return code.get();
}
public void setSubCode(String subCode) {
code.set(subCode);
}
public String getSubRev() {
return rev.get();
}
public void setSubRev(String subRev) {
rev.set(subRev);
}
}