Android连接MySQL问题，驱动加载成功，连接却失败

Question

import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.widget.TextView; import java.sql.Connection; import java.sql.DriverManager; import java.sql.SQLException; public class MainActivity extends AppCompatActivity {     private TextView textView,textTwo;     private final static String URL = "jdbc:mysql://localhost:3306/librarydb";     static String rootName = "root";     static String PWD = "1997831";     @Override     protected void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);         setContentView(R.layout.activity_main);         textView= (TextView) findViewById(R.id.textView);         textTwo= (TextView) findViewById(R.id.textTwo);         try {             Class.forName("com.mysql.jdbc.Driver");             textView.setText("驱动加载成功");         } catch (ClassNotFoundException e) {             textView.setText("找不到驱动程序类 ，加载驱动失败！");             e.printStackTrace();         }         new Thread(new Runnable() {             @Override             public void run() {                 try {                     Connection conn= conn = (Connection) DriverManager.getConnection(URL,rootName,PWD);                     textTwo.setText("数据库连接成功！");                 } catch (SQLException e) {                     textTwo.setText("数据库连接失败！");                     e.printStackTrace();                 }             }         }).start();     } }

Answer 1

已解决