JDBC（通俗易懂）简单的操作（增、删、改、查）

项目所写的类：

说明：①、DButil 动态加载数据库驱动，以及获取java.sql.Connection的对象。

②、Personmodel 数据库列（栏位）所对应的字段，定义了相应的set和get方法。

③、Persondao 对数据库相应的增删改查方法 。

④、Personaction 对Persondao里面增删改查方法的进一步补充完善。

⑤、Personview 对应的将要展示数据的类

①②③④⑤的代码：

package DB;

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.ResultSet;

import java.sql.SQLException;

import java.sql.Statement;

public class DButil {

private static Connection connection;

static {

try {

//动态加载数据库驱动，注意要下载JDBC的jar包

Class.forName("com.mysql.jdbc.Driver");

//获得链接

connection = DriverManager.getConnection("jdbc:mysql://192.168.0.103:3306/testjdbc", "root","15090183397");

} catch (ClassNotFoundException e) {

// TODO Auto-generated catch block

e.printStackTrace();

} catch (SQLException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

public static Connection getConnection() {

return connection;

}

}

先定义静态变量 connection，然后在静态代码段里面动态加载数据库驱动，并获得链接connection对象，然后定义get方法获取到该connection对象，以后需要与数据库建立连接进行相关操作的话，只要调用DButil的getconnection()方法即可。

②代码：

package DBmodel;

import java.util.Date;

public class Personmodel {

private Integer id;

private String name;

private String sex;

private String birthday;

private String phone;

private String email;

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 String getBirthday() {

return birthday;

}

public void setBirthday(String birthday) {

this.birthday = birthday;

}

public String getPhone() {

return phone;

}

public void setPhone(String phone) {

this.phone = phone;

}

public String getEmail() {

return email;

}

public void setEmail(String email) {

this.email = email;

}

}

数据库设计表:

Personmodel模型类对应数据库的相应列（栏位），然后将数据库相应栏位的操作对应到Personmodel类的某个对象中，然后进行操作，这就是Personmodel模型类的作用。

③如下：

package Dao;

import java.sql.Connection;

import java.sql.Date;

import java.sql.PreparedStatement;

import java.sql.ResultSet;

import java.sql.SQLException;

import java.sql.Statement;

import java.util.ArrayList;

import java.util.List;

import java.util.Scanner;

import DB.DButil;

import DBmodel.Personmodel;

public class Persondao {

private static List<Personmodel> personmodels = new ArrayList<Personmodel>();

@SuppressWarnings("unused")

private Scanner scanner = new Scanner(System.in);

public static void addperson(Personmodel personmodel) throws SQLException {

Connection connection = DButil.getConnection();

String sql = " insert person " + " (name,sex,birthday,phone,email) "

+ " values(?,?,?,?,?);";

PreparedStatement preparedStatement = connection.prepareStatement(sql);

preparedStatement.setString(1, personmodel.getName());

preparedStatement.setString(2, personmodel.getSex());

preparedStatement.setString(3, personmodel.getBirthday());

preparedStatement.setString(4, personmodel.getEmail());

preparedStatement.setString(5, personmodel.getEmail());

preparedStatement.execute();

}

public static void deleteperson(Integer id) throws SQLException {

Connection connection = DButil.getConnection();

String sql = " delete from person " + " where id=?;";

PreparedStatement preparedStatement = connection.prepareStatement(sql);

preparedStatement.setInt(1, id);

preparedStatement.execute();

System.out.println("指定记录删除成功！");

}

public static void updateperson(Personmodel personmodel)

throws SQLException {

Connection connection = DButil.getConnection();

String sql = " update person "

+ " set name=?,sex=?,birthday=?,phone=?,email=?"

+ " where id=?;";

PreparedStatement preparedStatement = connection.prepareStatement(sql);

preparedStatement.setString(1, personmodel.getName());

preparedStatement.setString(2, personmodel.getSex());

preparedStatement.setString(3, personmodel.getBirthday());

preparedStatement.setString(4, personmodel.getPhone());

preparedStatement.setString(5, personmodel.getEmail());

preparedStatement.setInt(6, personmodel.getId());

preparedStatement.execute();

}

public static Personmodel queryoneperson(Integer id) throws SQLException {

Connection connection = DButil.getConnection();

String sql = "select * from person " + " where id=?;";

PreparedStatement preparedStatement = connection.prepareStatement(sql);

preparedStatement.setInt(1, id);

ResultSet resultSet = preparedStatement.executeQuery();

while (resultSet.next()) {

Personmodel personmodel = new Personmodel();

personmodel.setId(resultSet.getInt("id"));

personmodel.setName(resultSet.getString("name"));

personmodel.setSex(resultSet.getString("sex"));

personmodel.setBirthday(resultSet.getString("birthday"));

personmodel.setPhone(resultSet.getString("phone"));

personmodel.setEmail(resultSet.getString("email"));

return personmodel;

}

return null;

}

public static List<Personmodel> queryonepersonbyname(String name)

throws SQLException {

Connection connection = DButil.getConnection();

String sql = "select * from person " + " where name=?;";

PreparedStatement preparedStatement = connection.prepareStatement(sql);

preparedStatement.setString(1, name);

ResultSet resultSet = preparedStatement.executeQuery();

Personmodel personmodel = null;

List<Personmodel> list = new ArrayList<Personmodel>();

while (resultSet.next()) {

personmodel= new Personmodel();

personmodel.setId(resultSet.getInt("id"));

personmodel.setName(resultSet.getString("name"));

personmodel.setSex(resultSet.getString("sex"));

personmodel.setBirthday(resultSet.getString("birthday"));

personmodel.setPhone(resultSet.getString("phone"));

personmodel.setEmail(resultSet.getString("email"));

list.add(personmodel);

}

return list;

}

public static List<Personmodel> queryallperson() throws SQLException {

Connection connection = DButil.getConnection();

Statement statement = connection.createStatement();

ResultSet resultSet = statement.executeQuery("select * from person");

while (resultSet.next()) {

Personmodel personmodel = new Personmodel();

personmodel.setId(resultSet.getInt("id"));

personmodel.setName(resultSet.getString("name"));

personmodel.setSex(resultSet.getString("sex"));

personmodel.setBirthday(resultSet.getString("birthday"));

personmodel.setPhone(resultSet.getString("phone"));

personmodel.setEmail(resultSet.getString("email"));

personmodels.add(personmodel);

}

return personmodels;

}

}

这里面写的是数据库的增删改查操作， 首先看第一个方法是增加方法addperson()大家看方法里面代码，先获得connection对象，然后获得预编译对象 preparedStatement ，注意获得对象时调用方法的sql字符串参数，那个是将来要执行的SQL语句，下面preparedStatement的setxxx方法,里面第一个参数值对应sql字符串里面的相应?，第二个参数用了Personmodel的get方法（ preparedStatement .setxxx参数意义可百度或查阅api），然后你会问了，那是什么时候进行的set赋值呢？问得好，这时候Personaction类的意义就显示出来了，里面有相对应的方法对Persondao的增删改查补充完善的相应方法，采用该方式逻辑更加清晰，我举例了addperson()增加记录方法的解释，其他类似。

④如下：

package Action;

import java.sql.SQLException;

import java.util.Date;

import java.util.Iterator;

import java.util.List;

import java.util.Scanner;

import DBmodel.Personmodel;

import Dao.Persondao;

public class Personaction {

// private static Persondao persondao;

private static Scanner scanner = new Scanner(System.in);

public static void addone() throws SQLException {

Personmodel personmodel = new Personmodel();

System.out.println("请依次输入要新增记录的以下属性值~");

System.out.println("姓名:");

personmodel.setName(scanner.next());

System.out.println("性别:");

personmodel.setSex(scanner.next());

System.out.println("生日(例如：1994-01-01):");

personmodel.setBirthday(scanner.next());

System.out.println("电话:");

personmodel.setPhone(scanner.next());

System.out.println("邮箱:");

personmodel.setEmail(scanner.next());

Persondao.addperson(personmodel);

System.out.println("指定记录添加成功！");

}

public static boolean deleteone() throws SQLException {

List<Personmodel> personmodels = Persondao.queryallperson();

String stringid = null;

while (true) {

System.out.println("请输入要删除记录的指定id：");

stringid= scanner.next();

if (!stringid.matches("\\d+")) {

System.out.println("请输入正整数！");

continue;

}

break;

}

int id = Integer.valueOf(stringid);

for (Personmodel personmodel : personmodels) {

if (personmodel.getId() == id) {

Persondao.deleteperson(id);

System.out.println("删除成功，删除id为" + id + "的数据~");

return true;

}

}

System.out.println("删除失败，指定id不存在~");

return false;

}

 

public static boolean update() throws SQLException {

List<Personmodel> personmodels = Persondao.queryallperson();

String stringid = null;

while (true) {

System.out.println("请输入要修改记录的指定id：");

stringid= scanner.next();

if (!stringid.matches("\\d+")) {

System.out.println("请输入正整数！");

continue;

}

break;

}

int id = Integer.valueOf(stringid);

for (Personmodel personmodel2 : personmodels) {

if (personmodel2.getId() == id) {

Personmodel personmodel = new Personmodel();

personmodel.setId(id);

System.out.println("请依次输入要更改记录的以下属性值~");

System.out.println("姓名:");

personmodel.setName(scanner.next());

System.out.println("性别:");

personmodel.setSex(scanner.next());

System.out.println("生日(例如：1994-01-01):");

personmodel.setBirthday(scanner.next());

System.out.println("电话:");

personmodel.setPhone(scanner.next());

System.out.println("邮箱:");

personmodel.setEmail(scanner.next());

Persondao.updateperson(personmodel);

System.out.println("指定记录修改成功！");

return true;

}

}

System.out.println("要修改的id记录不存在！");

return false;

}

 

public static boolean selectone() throws SQLException {

List<Personmodel> personmodels = Persondao.queryallperson();

String stringid = null;

while (true) {

System.out.println("请输入要查询记录的指定id：");

stringid= scanner.next();

if (!stringid.matches("\\d+")) {

System.out.println("请输入正整数！");

continue;

}

break;

}

int id = Integer.valueOf(stringid);

for (Personmodel personmodel : personmodels) {

if (personmodel.getId() == id) {

personmodel= Persondao.queryoneperson(id);

System.out.println("查询成功，id为" + id + "的数据：");

System.out.print("|");

System.out.print("学生编号：" + personmodel.getId() + " ");

System.out.print("姓名：" + personmodel.getName() + " ");

System.out.print("性别：" + personmodel.getSex() + " ");

System.out.print("生日：" + personmodel.getBirthday() + " ");

System.out.print("电话：" + personmodel.getPhone() + " ");

System.out.print("邮件：" + personmodel.getEmail() + " ");

System.out.println();

return true;

}

}

System.out.println("查询失败，指定id不存在~");

return false;

}

 

public static boolean selectonebyname() throws SQLException {

List<Personmodel> personmodels = Persondao.queryallperson();

System.out.println("请输入要查询记录的指定姓名：");

String name = scanner.next();

for (Personmodel personmodel2 : personmodels) {

if (personmodel2.getName().equals(name)) {

List<Personmodel> list = Persondao.queryonepersonbyname(name);

for (int i = 0; i < list.size(); i++) {

Personmodel personmodel = list.get(i);

System.out.println("查询成功，姓名为" + name + "的数据：");

System.out.print("|");

System.out.print("学生编号：" + personmodel.getId() + " ");

System.out.print("姓名：" + personmodel.getName() + " ");

System.out.print("性别：" + personmodel.getSex() + " ");

System.out.print("生日：" + personmodel.getBirthday() + " ");

System.out.print("电话：" + personmodel.getPhone() + " ");

System.out.print("邮件：" + personmodel.getEmail() + " ");

System.out.println();

}

return true;

}

}

System.out.println("查询失败，指定id不存在~");

return false;

}

 

public static void selectall() throws SQLException {

List<Personmodel> personmodels = Persondao.queryallperson();

for (Personmodel personmodel : personmodels) {

System.out.print("|");

System.out.print("学生编号：" + personmodel.getId() + " ");

System.out.print("姓名：" + personmodel.getName() + " ");

System.out.print("性别：" + personmodel.getSex() + " ");

System.out.print("生日：" + personmodel.getBirthday() + " ");

System.out.print("电话：" + personmodel.getPhone() + " ");

System.out.print("邮件：" + personmodel.getEmail() + " ");

System.out.println();

}

}

}

刚才讲③的时候，为了大家的方便理解我顺带解释了④，大家看代码即可，我不再赘述啦。需要注意的一点是，我进行了控制台输入语句的判断，判断是否是合法类型。

最后是⑤，代码如下：

package View;

import java.sql.SQLException;

import java.util.Scanner;

import Action.Personaction;

import Dao.Persondao;

public class Personview {

public static Scanner scanner = new Scanner(System.in);

public static void main(String[] args) throws SQLException {

while (true) {

System.out.println("以下是数据库的各种操作：（标号为对应操作）");

System.out.println("0、退出数据库操作：");

System.out.println("1、查询全部记录：");

System.out.println("2、新增单条记录：");

System.out.println("3、更新单条记录：");

System.out.println("4、查询单条记录(通过id查询)：");

System.out.println("5、查询部分记录(通过name查询)：");

System.out.println("6、删除单条记录(通过id删除)：");

String actionid = scanner.next();

// ("\\d+")是正则表达是，判断是否是数字

if (!actionid.matches("\\d+")) {

System.out.println("请输入正整数！");

continue;

}

int idchose = Integer.valueOf(actionid);

if (idchose == 0) {

break;

}

switch (idchose) {

case 1:

Personaction.selectall();

break;

case 2:

Personaction.addone();

break;

case 3:

Personaction.update();

break;

case 4:

Personaction.selectone();

break;

case 5:

Personaction.selectonebyname();

break;

case 6:

Personaction.deleteone();

break;

case 7:

break;

default:

System.out.println("请选择0-7之间操作~");

break;

}

}

// persondao = new Persondao();

// Personaction.addone();

// Personaction.deleteone();

// Personaction.selectall();

// Personaction.selectone();

// Personaction.update();

// Personaction.selectonebyname();

}

}

注意看我的Personview的逻辑设计，主要采用了while循环的方式，不过也有相应的退出操作以及判断是否合法代码，感觉这种方式的设计还是相当容易看懂的。

以上要分享的代码都贴了，该说的也说了，相信大家也都看得明白吧，如果你觉得我的文章对你有帮助的话，还希望你点赞、分享、转发，让更多的人看到，互相学习，交流！ 好了，大家下篇文章见~~