用Java连接到MySQL数据库

Question

Can anyone help me out with this error here? Is it a syntax error?

Username:root No password

Code:

    Class.forName("com.mysql.jdbc.Driver");

    Connection conn = null;
    conn = DriverManager.getConnection("jdbc:mysql://localhost/main"
            + "user=root&password=");

Output:

Access denied for user ''@'localhost' to database 'mainuser=root&password='

Answer 1

You missed ? before user .

DriverManager.getConnection("jdbc:mysql://localhost/main?" +
                               "user=root&password=");

It's worth reading Oracle Tutorial - Establishing a Connection

---

You can try with Properties as well. Look at DriverManager.getConnection(String,Properties) constructor and there are more try with any one.

Properties connectionProps = new Properties();
connectionProps.put("user", "root");
connectionProps.put("password", "");

String url ="jdbc:mysql://localhost/main";

Connection conn = DriverManager.getConnection(url, connectionProps);

Answer 2

You can use the following method signature instead

public static Connection getConnection(String url, String user, String password) throws SQLException

In your case it will be

conn = DriverManager.getConnection("jdbc:mysql://localhost/main", "root", "");

Answer 3

You're doing it wrong Try this

(Jdbc:mysql://localhost/main,root,passwd)