zoukankan      html  css  js  c++  java
  • jdbc --例子7

    package cn.kitty.o1;
    
    import java.sql.Connection;
    import java.sql.DriverManager;
    import java.sql.SQLException;
    
    public class Test {
        
      public static void main(String[] args){
        Connection conn=null;
    
        try {
            Class.forName("com.mysql.jdbc.Driver");
        } catch (ClassNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        //2.
        try {
            conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/epet?useUnicode=true&characterEncoding=utf-8","root","");
            System.out.println("连接成功");
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }finally{
            //3
            if (null!=conn) {
                try {
                    conn.close();
                } catch (SQLException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }
        }
        
    }
    }
    package cn.kitty.o1;
    
    
    import java.sql.Connection;
    import java.sql.DriverManager;
    import java.sql.SQLException;
    import java.sql.Statement;
    
    //Statement
    public class Test02 {
      public static void main(String[] args) {
        Connection conn=null;
        Statement stmt=null;
        String name="kitty";
        int health=100;
        int love =10;
        String strain="可爱的小公举3";
        //1
        try {
            Class.forName("com.mysql.jdbc.Driver");
        } catch (ClassNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        //2.
        try {
            conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/epet","root","");
        } catch (SQLException e1) {
            // TODO Auto-generated catch block
            e1.printStackTrace();
        }
        //3.
        try {
            stmt=conn.createStatement();
        } catch (SQLException e1) {
            // TODO Auto-generated catch block
            e1.printStackTrace();
        }
        StringBuffer sbSql=new StringBuffer(
                "insert into dog(name,health,love,strain)values('");
                        sbSql.append(name+"',");
                        sbSql.append(health+",");
                        sbSql.append(love+",'");
                        sbSql.append(strain+"')");
                        try {
                            stmt.execute(sbSql.toString());
                            System.out.println("添加数据成功");
                        } catch (SQLException e) {
                            // TODO Auto-generated catch block
                            e.printStackTrace();
                        }finally{
                                    try {
                                        if (null !=stmt) {
                                        stmt.close();
                                        }
                                    } catch (SQLException e) {
                                        // TODO Auto-generated catch block
                                        e.printStackTrace();
                                    }
                                
                                    try {
                                        if(null!=conn){
                                        conn.close();
                                        }
                                    } catch (SQLException e) {
                                        // TODO Auto-generated catch block
                                        e.printStackTrace();
                                    
                                }
                        }
        
    }
    }
    package cn.kitty.o1;
    
    import java.sql.Connection;
    import java.sql.DriverManager;
    import java.sql.SQLException;
    import java.sql.Statement;
    
    //更新宠物Statement
    public class Test03 {
        public static void main(String[] args) {
            Connection conn=null;
            Statement stmt=null;
            
            //1.加载驱动
            try {
                Class.forName("com.mysql.jdbc.Driver");
            } catch (ClassNotFoundException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            //2.建立连接
            try {
                conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/epet","root","");
            
                stmt=conn.createStatement();
                stmt.executeUpdate("update dog set health=1000,love=1500 where id=1");
                System.out.println("成功更新狗狗信息");
            } catch (SQLException e1) {
                // TODO Auto-generated catch block
                e1.printStackTrace();
            }finally{
                                       try {
                                            if (null !=stmt) {
                                            stmt.close();
                                            }
                                        } catch (SQLException e) {
                                            // TODO Auto-generated catch block
                                            e.printStackTrace();
                                        }
                                    
                                        try {
                                            if(null!=conn){
                                            conn.close();
                                            }
                                        } catch (SQLException e) {
                                            // TODO Auto-generated catch block
                                            e.printStackTrace();
                                        
                                    }
                            }
            
        }
    
    }
      
    package cn.kitty.o1;
    
    import java.sql.Connection;
    import java.sql.DriverManager;
    import java.sql.ResultSet;
    import java.sql.SQLException;
    import java.sql.Statement;
    
    //查询所有宠物Statement和ResultSet
    public class Test04 {
    public static void main(String[] args) {
        Connection conn=null;
        Statement stmt=null;
        ResultSet rs=null;
        //1
            try {
                Class.forName("com.mysql.jdbc.Driver");
            } catch (ClassNotFoundException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            //2.
            try {
                conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/epet","root","");
            } catch (SQLException e1) {
                // TODO Auto-generated catch block
                e1.printStackTrace();
            }
            //3.查询并输入狗狗信息
            try {
                stmt=conn.createStatement();
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            try {
                rs=stmt.executeQuery("select id,name,health,love,strain from dog");
                System.out.println("狗狗信息列表");
                System.out.println("编号	姓名	健康值	亲密度	品种");
                while(rs.next()){
                    System.out.print(rs.getInt(1)+"	");
                    System.out.print(rs.getString(2)+"	");
                    System.out.print(rs.getInt("health")+"	");
                    System.out.print(rs.getInt("love")+"	");
                    System.out.println(rs.getString("strain"));
                }
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }finally{
                if(null!=rs){
                    try {
                        rs.close();
                    } catch (SQLException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                }
                if(null!=stmt){
                    try {
                        stmt.close();
                    } catch (SQLException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                }
                if(null!=conn){
                    try {
                        conn.close();
                    } catch (SQLException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                }
            }
            
    }
    }
    package cn.kitty.o1;
    
    import java.sql.Connection;
    import java.sql.DriverManager;
    import java.sql.ResultSet;
    import java.sql.SQLException;
    import java.sql.Statement;
    
    //查询并输出宠物主人信息
    public class Test05 {
       public static void main(String[] args) {
           Connection conn=null;
            Statement stmt=null;
            ResultSet rs=null;
            //1
                try {
                    Class.forName("com.mysql.jdbc.Driver");
                } catch (ClassNotFoundException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
                //2.
                try {
                    conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/epet","root","");
                } catch (SQLException e1) {
                    // TODO Auto-generated catch block
                    e1.printStackTrace();
                }
                //3.
                try {
                    stmt=conn.createStatement();
                } catch (SQLException e1) {
                    // TODO Auto-generated catch block
                    e1.printStackTrace();
                }
                try {
                    rs=stmt.executeQuery("select id ,name,money from master");
                } catch (SQLException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
                System.out.println("主人信息列表");
                System.out.println("编号	姓名	元宝数");
                try {
                    while(rs.next()){
                        System.out.print(rs.getInt("id")+"	");
                        System.out.print(rs.getString("name")+"	");
                        System.out.println(rs.getInt("money"));
                        
                    }
                } catch (SQLException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }finally{
                    if(null!=rs){
                        try {
                            rs.close();
                        } catch (SQLException e) {
                            // TODO Auto-generated catch block
                            e.printStackTrace();
                        }
                    }
                    if(null!=stmt){
                        try {
                            stmt.close();
                        } catch (SQLException e) {
                            // TODO Auto-generated catch block
                            e.printStackTrace();
                        }
                    }
                    if(null!=conn){
                        try {
                            conn.close();
                        } catch (SQLException e) {
                            // TODO Auto-generated catch block
                            e.printStackTrace();
                        }
                    }
                }
       }
    }
    package cn.kitty.o1;
    
    import java.sql.Connection;
    import java.sql.DriverManager;
    import java.sql.ResultSet;
    import java.sql.SQLException;
    import java.sql.Statement;
    import java.util.Scanner;
    
    //
    public class Test06 {
    public static void main(String[] args) {
         Connection conn=null;
            Statement stmt=null;
            ResultSet rs=null;
            //根据控制台提示输入用户账号和密码
            Scanner input =new Scanner(System.in);
            System.out.println("宠物主人登录");
            System.out.println("请输入姓名:");
            String name =input.next();
            System.out.println("请输入密码:");
            String password=input.next();
            //1.加载驱动
            try {
                Class.forName("com.mysql.jdbc.Driver");
            } catch (ClassNotFoundException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            //2.
            try {
                conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/epet?useUnicode=true&characterEncoding=utf-8","root","");
            } catch (SQLException e1) {
                // TODO Auto-generated catch block
                e1.printStackTrace();
            }
            //判断宠物主人登录成功
            try {
                stmt=conn.createStatement();
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            String sql="select * from master where name='"+name+"' and password='"+password+"'";
            System.out.println(sql);
            try {
                rs=stmt.executeQuery(sql);
            } catch (SQLException e1) {
                // TODO Auto-generated catch block
                e1.printStackTrace();
            }
            try {
                if(rs.next())
                    System.out.println("登录成功,欢迎你");
                else
                    System.out.println("登录失败,请重新输入!");
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }finally{
                if(null!=rs){
                    try {
                        rs.close();
                    } catch (SQLException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                }
                if(null!=stmt){
                    try {
                        stmt.close();
                    } catch (SQLException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                }
                if(null!=conn){
                    try {
                        conn.close();
                    } catch (SQLException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                }
            }
            
         }
    }
    package cn.kitty.o1;
    
    import java.sql.Connection;
    import java.sql.DriverManager;
    import java.sql.PreparedStatement;
    import java.sql.SQLException;
    
    
    
    //preparedStatment 更新多条狗狗信息
    public class Test07 {
        public static void main(String[] args) {
            Connection conn=null;
            PreparedStatement pstmt=null;
            //1.加载驱动
            try {
                Class.forName("com.mysql.jdbc.Driver");
            } catch (ClassNotFoundException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            //2.建立连接
            try {
                conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/epet?useUnicode=true&characterEncoding=utf-8","root","");
            } catch (SQLException e1) {
                // TODO Auto-generated catch block
                e1.printStackTrace();
            }
            //3.更新狗狗数据到数据库
            String sql="update dog set health=?,love=? where id=?";
            try {
                pstmt=conn.prepareStatement(sql);
            } catch (SQLException e1) {
                // TODO Auto-generated catch block
                e1.printStackTrace();
            }
            try {
                pstmt.setInt(1, 90);
                pstmt.setInt(2, 90);
                pstmt.setInt(3, 1);
                pstmt.executeUpdate();
                pstmt.setInt(1, 90);
                pstmt.setInt(2, 90);
                pstmt.setInt(3, 2);
                pstmt.executeUpdate();
                System.out.println("更新狗狗信息成功");
            } catch (SQLException e1) {
                // TODO Auto-generated catch block
                e1.printStackTrace();
            }finally{
                
            
                if(null!=pstmt){
                    try {
                        pstmt.close();
                    } catch (SQLException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                }
                if(null!=conn){
                    try {
                        conn.close();
                    } catch (SQLException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                }
                
            
            }
    
    }}
  • 相关阅读:
    损失函数及经验风险和结构风险
    ML面试题网站及ML模型网站
    数据归一化
    逻辑回归
    什么是凸函数及如何判断一个函数是否是凸函数
    Feature Selection Can Reduce Overfitting And RF Show Feature Importance
    Python Machine Learning-Chapter4
    skywalking与pinpoint全链路追踪方案对比
    全)Java从单体到微服务打造房产销售平台 2018年慕课网 高清视频+源码
    CentOS7 通过YUM安装MySQL5.7
  • 原文地址:https://www.cnblogs.com/cuixiaomeng/p/7169330.html
Copyright © 2011-2022 走看看