项目结构
新建SpringBoot项目
$ tree
.
├── pom.xml
└── src
├── main
│ ├── java
│ │ └── com
│ │ └── example
│ │ └── demo
│ │ ├── Application.java
│ │ ├── bean
│ │ │ ├── RequestPage.java
│ │ │ └── User.java
│ │ ├── controller
│ │ │ └── UserController.java
│ │ ├── dao
│ │ │ └── UserDao.java
│ │ └── service
│ │ ├── UserService.java
│ │ └── impl
│ │ └── UserServiceImpl.java
│ └── resources
│ └── application.properties
└── test
依赖和配置
pom.xml
<!--MyBatis-->
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>2.1.3</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>
<!--分页插件-->
<dependency>
<groupId>com.github.pagehelper</groupId>
<artifactId>pagehelper-spring-boot-starter</artifactId>
<version>1.2.13</version>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
application.properties
spring.datasource.url=jdbc:mysql://localhost:3306/data
spring.datasource.username=root
spring.datasource.password=123456
mybatis.configuration.log-impl=org.apache.ibatis.logging.stdout.StdOutImpl
表结构
CREATE TABLE `user` (
`id` int(13) NOT NULL AUTO_INCREMENT COMMENT '主键',
`name` varchar(33) DEFAULT NULL COMMENT '姓名',
`age` int(3) DEFAULT NULL COMMENT '年龄',
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8
相关代码
User.java
package com.example.demo.bean;
import lombok.Data;
@Data
public class User {
private Integer id;
private String name;
private Integer age;
}
RequestPage.java
package com.example.demo.bean;
import org.springframework.util.StringUtils;
/**
* 分页所需参数
*/
public class RequestPage {
private Integer page;
private Integer size;
/**
* 页码,为非必传参数,默认值为 1
*/
public Integer getPage() {
return StringUtils.isEmpty(page) ? 1 : page;
}
public void setPage(Integer page) {
this.page = page;
}
/**
* 大小,非必传参数,默认值为 10
*/
public Integer getSize() {
return StringUtils.isEmpty(size) ? 10 : size;
}
public void setSize(Integer size) {
this.size = size;
}
}
UserDao.java
package com.example.demo.dao;
import com.example.demo.bean.User;
import com.github.pagehelper.Page;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Select;
import java.util.List;
@Mapper
public interface UserDao {
@Select("select * from user")
Page<User> selectAllUserPage();
@Select("select * from user")
List<User> selectAllUserList();
}
UserService.java
package com.example.demo.service;
import com.example.demo.bean.User;
import com.github.pagehelper.Page;
import java.util.List;
public interface UserService {
Page<User> selectAllUserPage();
List<User> selectAllUserList();
}
UserServiceImpl.java
package com.example.demo.service.impl;
import com.example.demo.bean.User;
import com.example.demo.dao.UserDao;
import com.example.demo.service.UserService;
import com.github.pagehelper.Page;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import java.util.List;
@Service
public class UserServiceImpl implements UserService {
@Autowired
UserDao userDao;
@Override
public Page<User> selectAllUserPage() {
return userDao.selectAllUserPage();
}
@Override
public List<User> selectAllUserList() {
return userDao.selectAllUserList();
}
}
UserController.java
package com.example.demo.controller;
import com.example.demo.bean.RequestPage;
import com.example.demo.bean.User;
import com.example.demo.service.UserService;
import com.github.pagehelper.Page;
import com.github.pagehelper.PageHelper;
import com.github.pagehelper.PageInfo;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
import java.util.List;
@RestController
public class UserController {
@Autowired
UserService userService;
/**
* 返回数据列表和分页信息
* @param requestPage
* @return
*/
@GetMapping("selectAllUserPage")
public PageInfo<User> selectAllUserPage(RequestPage requestPage){
PageHelper.startPage(requestPage.getPage(), requestPage.getSize());
Page<User> page = userService.selectAllUserPage();
PageInfo<User> pageInfo = new PageInfo<>(page);
return pageInfo;
}
/**
* 返回数据列表
* @param requestPage
* @return
*/
@GetMapping("selectAllUserList")
public List<User> selectAllUserList(RequestPage requestPage){
PageHelper.startPage(requestPage.getPage(), requestPage.getSize());
List<User> list = userService.selectAllUserList();
return list;
}
}
访问测试
GET http://localhost:8080/selectAllUserList?page=2&size=1
[
{
id: 2,
name: "Tom",
age: 25
}
]
执行sql
==> Preparing: SELECT count(0) FROM user
==> Parameters:
<== Columns: count(0)
<== Row: 2
<== Total: 1
==> Preparing: select * from user LIMIT ?, ?
==> Parameters: 1(Integer), 1(Integer)
<== Columns: id, name, age, money
<== Row: 2, Tom, 25, 30.5
<== Total: 1
GET http://localhost:8080/selectAllUserPage?page=2&size=1
{
total: 2,
list: [
{
id: 2,
name: "Tom",
age: 25
}
],
pageNum: 2,
pageSize: 1,
size: 1,
startRow: 2,
endRow: 2,
pages: 2,
prePage: 1,
nextPage: 0,
isFirstPage: false,
isLastPage: true,
hasPreviousPage: true,
hasNextPage: false,
navigatePages: 8,
navigatepageNums: [
1,
2
],
navigateFirstPage: 1,
navigateLastPage: 2
}
==> Preparing: SELECT count(0) FROM user
==> Parameters:
<== Columns: count(0)
<== Row: 2
<== Total: 1
==> Preparing: select * from user LIMIT ?, ?
==> Parameters: 1(Integer), 1(Integer)
<== Columns: id, name, age, money
<== Row: 2, Tom, 25, 30.5
<== Total: 1