Question

我有一个Android应用程序，并尝试连接到我在heroku中创建的数据库。我不断得到一个例外。我得到了sqlexception：没有合适的驱动程序。这是我的代码：这是我执行sql语句并尝试建立连接的类。

public class DB_Connection
{
public static final String DATABASE_URL  =
"postgres://iiuoxigyfsvsnd:aI8qkTno1bXZYtB74VovkMo75o@ec2-23-23-22550.compute-1.amazonaws.com:5432/dfpa4aagbgfcd7";
public int value;
// the empty constructor. without this we cant call DB_Connection.getConnection() from another class.
DB_Connection()
{
    value = 0;
}

/*
This is the method that opens the actual connection mto the Heroku Server
*/
protected static Connection getConnection() throws URISyntaxException, SQLException
{

    URI dbUri = new URI(DATABASE_URL);

    String username = dbUri.getUserInfo().split(":")[0];
    String password = dbUri.getUserInfo().split(":")[1];

    String dbUrl = "jdbc:postgresql://" + dbUri.getHost() + dbUri.getPath();
    System.err.println(dbUrl);
    Properties props = new Properties();
    props.setProperty("user", username);
    props.setProperty("password", password);
    props.setProperty("ssl", "true");
    props.setProperty("sslfactory", "org.postgresql.ssl.NonValidatingFactory");
    return DriverManager.getConnection(dbUrl, props);
}


public void userLogin(Connection cnct, String userE_Mail, String userPass)
{
    String results = new String();
    try
    {
        Statement stmt = cnct.createStatement();
        ResultSet rs = stmt.executeQuery("SELECT pass FROM users WHERE e_mail =" + userE_Mail + ";");
        while (rs.next())
        {
            results = rs.getNString("pass");
        }

        if (userPass == results)
        {
            value = 1;
        }
        else
        {
            results = "Invalid login. Please try again";
        }
    }
    catch (SQLException sqe)
    {
        System.out.println(sqe.getMessage());
        results = sqe.getMessage();
    }
    finally
    {
        if (cnct != null)
        {
            try
            {
                cnct.close();
            }
            catch (SQLException e)
            {

            }
        }
    }
}

/ * 去做：取回密码？ * /

public ArrayList getEvents(Connection cnct)
{
    ArrayList<DB_Event> eventList = null;
    ResultSet rs = null;
    try
    {
        Statement stmt = cnct.createStatement();
        rs = stmt.executeQuery("SELECT * FROM events");

        // every row returned by the databse is parsed into a DB_event
        // and added to an ArrayList<>.
        while (rs.next())
        {
            DB_Event event = new DB_Event(rs.getInt("event_id"),
                    rs.getNString("event_name"), rs.getDate("date_time"),
                    rs.getString("location"), rs.getNString("address"),
                    rs.getString("e-mail"));
            eventList.add(event);
        }
    }
    catch (SQLException sqe)
    {
        //TODO
    }
    return eventList;
}

}

这是我实际尝试使用它的类：

public class NewRegisterScreen extends ActionBarActivity
{
Connection cnct;
EditText number;
EditText password;
EditText fullName;
EditText email;
String firstName, lastName;
protected void onCreate(Bundle savedInstanceState)
{
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_register_screen);
    Button acceptButton = (Button) findViewById(R.id.acceptUserButton);

    fullName = (EditText) findViewById(R.id.enterName);
    password = (EditText) findViewById(R.id.editPassword);
    number = (EditText) findViewById(R.id.enterPhone);
    email = (EditText) findViewById(R.id.enterEmail);

    // new DB_connection established. Added by Christina
    DB_Connection DBcnct = new DB_Connection();
    try
    {
        cnct = DB_Connection.getConnection();
    }
    catch (URISyntaxException e)
    {
        System.err.println("Didn't connect");

    }
    catch (SQLException sqe)
    {
        sqe.printStackTrace();
        System.err.println("Didn't connect. Not sure why");
    }
}

我继续点击sqlexception，当我点击printstacktrace上的位置时，它表示在getConnection（）方法的类DB_Connection中发生错误，表明没有合适的驱动程序从该应用程序返回。任何人都可以告诉我为什么以及如何解决它？

从Android应用程序连接到heroku postgresql数据库的错误。没有合适的驱动程序SQLexception发生

0 个答案: