import java.sql.CallableStatement;   import java.sql.Connection;   import java.sql.DriverManager;   import java.sql.Types;         /*    * 对应的存储过程    DROP PROCEDURE IF EXISTS `pro_num_user`;   delimiter ;;   CREATE PROCEDURE `pro_num_user`(IN user_name varchar(10) ,OUT count_num INT)       READS SQL DATA   BEGIN       SELECT COUNT(*) INTO count_num FROM tab_user WHERE 'name'=user_name;   END    ;;   delimiter ;    */   public class Test {         public static final String DRIVER_CLASS = "com.mysql.jdbc.Driver";       public static final String URL = "jdbc:mysql://127.0.0.1:3306/test";       public static final String USERNAME = "root";       public static final String PASSWORD = "acbee";       public static void main(String[] args) throws Exception {           test1();           test2();       }              public static void test1() throws Exception       {           Class.forName(DRIVER_CLASS);           Connection connection = DriverManager.getConnection(URL, USERNAME, PASSWORD);           String sql = "{CALL pro_num_user(?,?)}"; //调用存储过程           CallableStatement cstm = connection.prepareCall(sql); //实例化对象cstm           cstm.setString(1, "myd"); //存储过程输入参数           //cstm.setInt(2, 2); // 存储过程输入参数           cstm.registerOutParameter(2, Types.INTEGER); // 设置返回值类型 即返回值           cstm.execute(); // 执行存储过程           System.out.println(cstm.getInt(2));           cstm.close();           connection.close();       }              public static void test2() throws Exception       {           Class.forName(DRIVER_CLASS);           Connection connection = DriverManager.getConnection(URL, USERNAME, PASSWORD);           String sql = "{CALL pro_number(?,?,?)}"; //调用存储过程           CallableStatement cstm = connection.prepareCall(sql); //实例化对象cstm           cstm.setInt(1, 2); // 存储过程输入参数           cstm.setInt(2, 2); // 存储过程输入参数           cstm.registerOutParameter(3, Types.INTEGER); // 设置返回值类型 即返回值           cstm.execute(); // 执行存储过程           System.out.println(cstm.getInt(3));           cstm.close();           connection.close();                  }   }