org.apache.derby.jdbc.ClientDriver ; 无法连接

Question

Unable to connect. Cannot establish a connection to jdbc:derby://localhost:1527/sample using org.apache.derby.jdbc.ClientDriver (DERBY SQL error: ERRORCODE: 40000, SQLSTATE: XJ040, SQLERRMC: Failed to start database 'sample' with class loader sun.misc.Launcher$AppClassLoader@1d44bcfa, see the next exception for details.::SQLSTATE: XSLAN).

Answer 1

When you do a connection you should put it into a try/catch. For example ( I use Java 8 and oracle SQLDeveloper ) :

 String dbURL="jdbc:oracle:thin:@localhost:1521:xe";
    String username = "system";
    String password = "root";


    try{

    Connection connection = DriverManager.getConnection(dbURL,username,password);
        System.out.println("Connected to Oracle database server");

        
        String sql = "INSERT INTO USERS (name,email,password)" + "VALUES('eu', 'eu@yahoo.com', 'eu')";

        Statement statement = connection.createStatement();
        int rows = statement.executeUpdate(sql);

        if(rows >0){
            System.out.println("A row has been inserted");
        }



        connection.close();
    }catch (SQLException e){
        System.out.println("ERROR");
    }

And always check for right password and username. Hope this helps. :D