我正在尝试使用Java更新oracle数据库中的密码。 难道我做错了什么？

Question

I am not getting any errors when running the emulator even when clicking on the button to change the password. I've tried everything I can think of does anyone know if i'm doing something wrong.

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.user_account);

Button to change password

    Button password = (Button) findViewById(R.id.btnChangePassword);
    password.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            try {
                update();
            } catch (Exception e) {
                e.printStackTrace();
            }

        }
    });}

Method to Update Password

public Exception update()throws Exception{
    Connection conn = null;
    Statement st = null;



    try {
        conn = ConnectionManager.getConnection();
        st = conn.createStatement();


        String select_password = "SELECT * From Userinfo Where USERID = 5";
        ResultSet Password = st.executeQuery(select_password);
        String password = "UPDATE userinfo SET PASSWORD = ? WHERE USERID = 5";

        while (Password.next()) {

            PreparedStatement ps = null; //conn.prepareStatement(Update_Bank);

           ps = conn.prepareStatement(password);
            String pass = "password123";
            ps.setString(1, pass);
            ps.executeUpdate();
            ps.close();
        }
        }catch(Exception e){
            return e;
        }
        return null;
}}

Ok so I changed some things up and I ran through the code and found it is failing at the "ResultSet Password = st.executeQuery(select_password);" statement. The thing is it works in eclipse but not in android studio. Anyone have any thoughts of why?

    Connection conn = null;
    Statement st = null;
    conn = ConnectionManager.getConnection();

    st = conn.createStatement();

    String select_password = "SELECT * From Userinfo Where USERID = 5";
    ResultSet Password = st.executeQuery(select_password);
    String password =( "UPDATE userinfo SET PASSWORD = ? WHERE USERID = 5");

    while (Password.next()) {
        PreparedStatement ps = conn.prepareStatement(password);
        ps = conn.prepareStatement(password);
        String pass = "password";
        ps.setString(1, pass);
        ps.executeUpdate();
        ps.close();
    }

}

Answer 1

You won't get any exceptions because you have a catch all statement inside update which you completely ignore by ignoring the return value of update!

After fixing that do the following:

• Make sure that the code inside the while loop is getting executed

• Check that the return value of executeUpdate is greater than 0

• In not familiar with this SQL syntax for changing password, have you tried running it directly in the console?

And a few bits of advice:

• You don't need the query since you are not using it's result set.

• Never use IDs. Use the user's name instead.

• Close the connection

• Never catch all Exceptions. If you do, never ever ignore when an exception is thrown.