问题描述

安卓新手用JDBC连接mysql时一直报错

抛出异常在logcat提示：驱动连接成功，数据库连接失败Could not find class 'javax.naming.StringRefAddr', referenced from method com.mysql.jdbc.ConnectionPropertiesImpl$ConnectionProperty.storeTo。求大神帮忙，错误围绕好长时间了

连接代码

 //连接数据库
 public static Connection getCon()
 {
  Connection conn = null;
  try {
   Class.forName("org.gjt.mm.mysql.Driver");
   System.out.println("驱动连接成功");
  } catch (ClassNotFoundException e1) {
   // TODO Auto-generated catch block
   System.out.println("驱动连接失败");
  }
     String dbUrl = "jdbc:mysql://localhost:3306/student";
     String username = "root";
     String psw = "1234";
  try {
   conn = DriverManager.getConnection(dbUrl,username,psw);
  } catch (SQLException e) {
   // TODO Auto-generated catch block
   System.out.println("数据库连接失败"+e);
  }
  return conn;
 }

解决方案

参考Connecting to MySQL from Android with JDBC
把数据库的部分放到AsyncTask或者Thread里面

public void mysql() {

    try {
        Class.forName("com.mysql.jdbc.Driver");
    } catch (ClassNotFoundException e) {
        e.printStackTrace();
    }

    thrd1 = new Thread(new Runnable() {
        public void run() {
            while (!Thread.interrupted()) {
                try {
                    Thread.sleep(100);
                } catch (InterruptedException e1) {

                }
                if (con == null) {
                    try {
                        con = DriverManager.getConnection("jdbc:mysql://192.168.1.45:3306/deneme", "ali", "12345");
                    } catch (SQLException e) {
                        e.printStackTrace();
                        con = null;
                    }

                    if ((thrd2 != null) && (!thrd2.isAlive()))
                        thrd2.start();
                }
            }
        }
    });
    if ((thrd1 != null) && (!thrd1.isAlive())) thrd1.start();

    thrd2 = new Thread(new Runnable() {
        public void run() {
            while (!Thread.interrupted()) {

                if (con != null) {
                    try {
                     //   con = DriverManager.getConnection("jdbc:mysql://192.168.1.45:3306/deneme", "ali", "12345");
                        Statement st = con.createStatement();
                        String ali = "'fff'";
                        st.execute("INSERT INTO deneme (name) VALUES(" + ali + ")");
                      //  ResultSet rs = st.executeQuery("select * from deneme");
                      //  ResultSetMetaData rsmd = rs.getMetaData();
                      //  String result = new String();

                      //  while (rs.next()) {
                      //      result += rsmd.getColumnName(1) + ": " + rs.getInt(1) + "n";
                     //       result += rsmd.getColumnName(2) + ": " + rs.getString(2) + "n";
                     //   }

                    } catch (SQLException e) {
                        e.printStackTrace();
                        con = null;
                    }

                    try {
                        Thread.sleep(10);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                } else {
                    try {
                        Thread.sleep(300);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                }
            }
        }
    });
}