错误信息:java.sql.SQLException;必须被捕获或声明为抛出

Question

所以我声明了一个SQL连接，如下所示:

public class db {
public void run() throws SQLException {
try {
Class.forName("com.mysql.cj.jdbc.Driver");
Connection cn = DriverManager.getConnection("jdbc:mysql://localhost:3306/project", "rizkiaswangga", "");
} catch (SQLException e) {
System.out.println(e.getMessage());
} catch (Exception e) {
System.out.println(e.getMessage());
}
}

}

我只是想先连接MariaDB到我的Java项目，但是，虽然我已经声明了SQLException，我仍然遇到如下错误消息:

Exception in thread "AWT-EventQueue-0" java.lang.RuntimeException: Uncompilable code - unreported exception java.sql.SQLException; must be caught or declared to be thrown

当我试图从其他类运行时:

public class Start extends javax.swing.JFrame {
/**
* Creates new form Start
*/
public Start() {
initComponents();
db myDb = new db();
myDb.run();
}

我的代码有什么问题?任何帮助都将是感激的:)

Answer 1

在运行方法中，您已经声明了throws SQLException，但您没有抛出异常。

在"启动方法"中还没有添加throws SQLException

。用public void run()法去除throw SQLException

public class db {
public void run() {
try {
Class.forName("com.mysql.cj.jdbc.Driver");
Connection cn = DriverManager.getConnection("jdbc:mysql://localhost:3306/project", "rizkiaswangga", "");
} catch (SQLException e) {
System.out.println(e.getMessage());
} catch (Exception e) {
System.out.println(e.getMessage());
}
}
}