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最新推荐文章于 2023-12-13 12:45:00 发布

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最新推荐文章于 2023-12-13 12:45:00 发布 · 568 阅读

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#java-ee #java

本文介绍了使用Java编写的Player类，包括DAO、Service、Controller和Servlet，展示了如何通过DBUtil连接数据库进行增删改查操作，并在JSP页面展示数据。涵盖了数据库操作、HTTP请求处理和前端显示。

整体结构

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model / entity

public class Player {
   
   
    private Integer id;
    private String name;
    private String sex;
    private Integer age;
    private String address;
    private String hobby;

    public String getHobby() {
   
   
        return hobby;
    }

    public void setHobby(String hobby) {
   
   
        this.hobby = hobby;
    }

    public Integer getId() {
   
   
        return id;
    }

    public void setId(Integer id) {
   
   
        this.id = id;
    }

    public String getName() {
   
   
        return name;
    }

    public void setName(String name) {
   
   
        this.name = name;
    }

    public String getSex() {
   
   
        return sex;
    }

    public void setSex(String sex) {
   
   
        this.sex = sex;
    }

    public Integer getAge() {
   
   
        return age;
    }

    public void setAge(Integer age) {
   
   
        this.age = age;
    }

    public String getAddress() {
   
   
        return address;
    }

    public void setAddress(String address) {
   
   
        this.address = address;
    }
}

dao

public class DBUtil {
   
   
    public static Connection getConnection() {
   
   
        Connection con = null;
        try {
   
   
            String driver = "com.mysql.jdbc.Driver";
            String url = "jdbc:mysql://localhost:3306/mydb?characterEncoding=utf-8";
            String user = "root";
            String password = "";
            Class.forName(driver);
            if(null == con) {
   
   
                con = DriverManager.getConnection(url, user, password);
            }
        } catch (ClassNotFoundException e) {
   
   
            e.printStackTrace();
        } catch (SQLException throwables) {
   
   
            throwables.printStackTrace();
        }
        return con;
    }
}

service

public class PlayerService {
   
   
    public int insertPlayer(Player player){
   
   
        int ret = 0;
        try {
   
   
            Connection con = DBUtil.getConnection();
            String sql = "insert into player values(null,?,?,?,?,?)";
            PreparedStatement stm = con.prepareStatement(sql);
            stm.setString(1,player.getName());
            stm.setString(2,player.getSex());
            stm.setInt(3,player.getAge());
            stm.setString(4,player.getAddress());
            stm.setString(5,player.getHobby());
            ret = stm.executeUpdate();
            stm.close();
            con.close();
        } catch (SQLException throwables) {
   
   
            throwables.printStackTrace();
        }
        return ret;
    }

    public int deletePlayer(int id){
   
   
        int ret = 0;
        try {
   
   
            Connection con = DBUtil.getConnection();
            String sql = "delete from player where PlayerID = ?";
            PreparedStatement stm = con.prepareStatement(sql);
            stm.setInt(1,id);
            ret = stm.executeUpdate();
            stm.close();
            con.close();
        } catch (SQLException throwables) {
   
   
            throwables.printStackTrace();
        }
        return ret;
    }

    public int updatePlayer(Player player){
   
   
        int ret = 0;
        try {
   
   
            Connection con = DBUtil.getConnection();
            String sql = "update player set Name=?,Sex=?,Age=?,Address=?,Hobby=? where PlayerID=?";
            PreparedStatement stm = con.prepareStatement(sql);
            stm.setString(1