import java.sql.*;
public class ConnectionProvider{
      private String JDBC_DRIVER;
      private String DB_URL;
      private String DB_USER;
      private String DB_PASSWORD;
      public ConnectionProvider() {
            JDBC_DRIVER=PropertyReader.get("JDBC_DRIVER");
            DB_URL=PropertyReader.get("DB_URL");
            DB_USER=PropertyReader.get("DB_USER");
            DB_PASSWORD=PropertyReader.get("DB_PASSWORD");
            try{
                  Class jdbcDriver=Class.forName(JDBC_DRIVER);
                  java.sql.DriverManager.registerDriver((Driver)jdbcDriver.newInstance());
      }catch(Exception e){e.printStackTrace();}
}
public Connection getConnection()throws SQLException{
      Connection con=java.sql.DriverManager.getConnection(DB_URL,DB_USER,DB_PASSWORD);
      return con;
}
}
import java.util.*;
import java.io.*;
public class PropertyReader {
      static private Properties ps;
      static{
            ps=new Properties();
            try{
                  InputStream in=PropertyReader.class.getResourceAsStream("db.txt");
                  ps.load(in);
                  in.close();
      }catch(Exception e){e.printStackTrace();}
}
public static String get(String key){
      return (String)ps.get(key);
}
}

JDBC_DRIVER = com.mysql.jdbc.Driver
DB_URL = jdbc:mysql://localhost:3306/STOREDB?useUnicode=true&characterEncoding=GB2312
DB_USER = root
DB_PASSWORD =123456
Exception in thread "main" java.sql.SQLException: Access denied for user 'root'@'localhost' (using password: YES)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:946)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:2870)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:812)
at com.mysql.jdbc.MysqlIO.secureAuth411(MysqlIO.java:3269)
at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1182)
at com.mysql.jdbc.Connection.createNewIO(Connection.java:2670)
at com.mysql.jdbc.Connection.<init>(Connection.java:1531)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:266)
at java.sql.DriverManager.getConnection(DriverManager.java:582)
at java.sql.DriverManager.getConnection(DriverManager.java:185)
at sql.ConnectionProvider.getConnection(ConnectionProvider.java:22)
at sql.DBTester2.addCustomer(DBTester2.java:13)
at sql.DBTester2.main(DBTester2.java:87)
------解决思路----------------------
Connection con=java.sql.DriverManager.getConnection(DB_URL,DB_USER,DB_PASSWORD);

--转自