本來地址:Spring Boot乾貨系列:(九)數據存儲篇-SQL關係型數據庫之MyBatis的使用
博客地址:tengj.top/javascript
上篇咱們介紹了Spring Boot對傳統JdbcTemplate的集成,此次換一下,介紹下Spring Boot中如何集成MyBatis。這裏分別介紹註解方式以及XML方式的整合。喜歡哪一種方式本身選擇。php
項目框架仍是跟上一篇同樣使用Spring Boot的ace後端模板,你能夠基於它來跟着博主一塊兒來調整代碼,若是沒看過上一篇,那就下載本篇源碼研究吧。html
跟上篇同樣先添加基礎的依賴和數據源。java
這裏須要添加mybatis-spring-boot-starter依賴跟mysql依賴mysql
<!--最新版本,匹配spring Boot1.5 or higher-->
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>1.3.0</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>複製代碼
這裏不引入spring-boot-starter-jdbc依賴,是因爲mybatis-spring-boot-starter中已經包含了此依賴。git
博主開始整理的時候發現mybatis-spring-boot-starter
有新版本了,這裏就集成最新的,匹配Spring Boot1.5版本。
github
MyBatis-Spring-Boot-Starter依賴將會提供以下:spring
就是說,使用了該Starter以後,只須要定義一個DataSource便可(application.properties中可配置),它會自動建立使用該DataSource的SqlSessionFactoryBean以及SqlSessionTemplate。會自動掃描你的Mappers,鏈接到SqlSessionTemplate,並註冊到Spring上下文中。sql
在src/main/resources/application.properties中配置數據源信息。數據庫
spring.datasource.url = jdbc:mysql://localhost:3306/spring?useUnicode=true&characterEncoding=utf-8
spring.datasource.username = root
spring.datasource.password = root
spring.datasource.driver-class-name = com.mysql.jdbc.Driver複製代碼
Spring Boot默認使用tomcat-jdbc數據源,若是你想使用其餘的數據源,好比這裏使用了阿里巴巴的數據池管理,除了在application.properties
配置數據源以外,你應該額外添加如下依賴:
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid</artifactId>
<version>1.0.19</version>
</dependency>複製代碼
修改Application.java
@SpringBootApplication
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
@Autowired
private Environment env;
//destroy-method="close"的做用是當數據庫鏈接不使用的時候,就把該鏈接從新放到數據池中,方便下次使用調用.
@Bean(destroyMethod = "close")
public DataSource dataSource() {
DruidDataSource dataSource = new DruidDataSource();
dataSource.setUrl(env.getProperty("spring.datasource.url"));
dataSource.setUsername(env.getProperty("spring.datasource.username"));//用戶名
dataSource.setPassword(env.getProperty("spring.datasource.password"));//密碼
dataSource.setDriverClassName(env.getProperty("spring.datasource.driver-class-name"));
dataSource.setInitialSize(2);//初始化時創建物理鏈接的個數
dataSource.setMaxActive(20);//最大鏈接池數量
dataSource.setMinIdle(0);//最小鏈接池數量
dataSource.setMaxWait(60000);//獲取鏈接時最大等待時間,單位毫秒。
dataSource.setValidationQuery("SELECT 1");//用來檢測鏈接是否有效的sql
dataSource.setTestOnBorrow(false);//申請鏈接時執行validationQuery檢測鏈接是否有效
dataSource.setTestWhileIdle(true);//建議配置爲true,不影響性能,而且保證安全性。
dataSource.setPoolPreparedStatements(false);//是否緩存preparedStatement,也就是PSCache
return dataSource;
}
}複製代碼
ok這樣就算本身配置了一個DataSource,Spring Boot會智能地選擇咱們本身配置的這個DataSource實例。
CREATE DATABASE /*!32312 IF NOT EXISTS*/`spring` /*!40100 DEFAULT CHARACTER SET utf8 */;
USE `spring`;
DROP TABLE IF EXISTS `learn_resource`;
CREATE TABLE `learn_resource` (
`id` bigint(20) NOT NULL AUTO_INCREMENT COMMENT 'ID',
`author` varchar(20) DEFAULT NULL COMMENT '做者',
`title` varchar(100) DEFAULT NULL COMMENT '描述',
`url` varchar(100) DEFAULT NULL COMMENT '地址連接',
PRIMARY KEY (`id`)
) ENGINE=MyISAM AUTO_INCREMENT=1029 DEFAULT CHARSET=utf8;
insert into `learn_resource`(`id`,`author`,`title`,`url`) values (999,'官方SpriongBoot例子','官方SpriongBoot例子','https://github.com/spring-projects/spring-boot/tree/master/spring-boot-samples');
insert into `learn_resource`(`id`,`author`,`title`,`url`) values (1000,'龍果學院','Spring Boot 教程系列學習','http://www.roncoo.com/article/detail/124661');
insert into `learn_resource`(`id`,`author`,`title`,`url`) values (1001,'嘟嘟MD獨立博客','Spring Boot乾貨系列','http://tengj.top/');
insert into `learn_resource`(`id`,`author`,`title`,`url`) values (1002,'後端編程嘟','Spring Boot視頻教程','http://www.toutiao.com/m1559096720023553/');複製代碼
不論是註解方式仍是XML配置的方式,如下代碼模塊都是同樣的
public class LearnResouce {
private Long id;
private String author;
private String title;
private String url;
// SET和GET方法
}複製代碼
/** 教程頁面 * Created by tengj on 2017/3/13. */
@Controller
@RequestMapping("/learn")
public class LearnController {
@Autowired
private LearnService learnService;
private Logger logger = LoggerFactory.getLogger(this.getClass());
@RequestMapping("")
public String learn(){
return "learn-resource";
}
@RequestMapping(value = "/queryLeanList",method = RequestMethod.POST,produces="application/json;charset=UTF-8")
@ResponseBody
public void queryLearnList(HttpServletRequest request ,HttpServletResponse response){
String page = request.getParameter("page"); // 取得當前頁數,注意這是jqgrid自身的參數
String rows = request.getParameter("rows"); // 取得每頁顯示行數,,注意這是jqgrid自身的參數
String author = request.getParameter("author");
String title = request.getParameter("title");
Map<String,Object> params = new HashMap<String,Object>();
params.put("page", page);
params.put("rows", rows);
params.put("author", author);
params.put("title", title);
List<LearnResouce> learnList=learnService.queryLearnResouceList(params);
PageInfo<LearnResouce> pageInfo =new PageInfo<LearnResouce>(learnList);
JSONObject jo=new JSONObject();
jo.put("rows", learnList);
jo.put("total", pageInfo.getPages());//總頁數
jo.put("records",pageInfo.getTotal());//查詢出的總記錄數
ServletUtil.createSuccessResponse(200, jo, response);
}
/** * 新添教程 * @param request * @param response */
@RequestMapping(value = "/add",method = RequestMethod.POST)
public void addLearn(HttpServletRequest request , HttpServletResponse response){
JSONObject result=new JSONObject();
String author = request.getParameter("author");
String title = request.getParameter("title");
String url = request.getParameter("url");
if(StringUtil.isNull(author)){
result.put("message","做者不能爲空!");
result.put("flag",false);
ServletUtil.createSuccessResponse(200, result, response);
return;
}
if(StringUtil.isNull(title)){
result.put("message","教程名稱不能爲空!");
result.put("flag",false);
ServletUtil.createSuccessResponse(200, result, response);
return;
}
if(StringUtil.isNull(url)){
result.put("message","地址不能爲空!");
result.put("flag",false);
ServletUtil.createSuccessResponse(200, result, response);
return;
}
LearnResouce learnResouce = new LearnResouce();
learnResouce.setAuthor(author);
learnResouce.setTitle(title);
learnResouce.setUrl(url);
int index=learnService.add(learnResouce);
if(index>0){
result.put("message","教程信息添加成功!");
result.put("flag",true);
}else{
result.put("message","教程信息添加失敗!");
result.put("flag",false);
}
ServletUtil.createSuccessResponse(200, result, response);
}
/** * 修改教程 * @param request * @param response */
@RequestMapping(value = "/update",method = RequestMethod.POST)
public void updateLearn(HttpServletRequest request , HttpServletResponse response){
JSONObject result=new JSONObject();
String id = request.getParameter("id");
LearnResouce learnResouce=learnService.queryLearnResouceById(Long.valueOf(id));
String author = request.getParameter("author");
String title = request.getParameter("title");
String url = request.getParameter("url");
if(StringUtil.isNull(author)){
result.put("message","做者不能爲空!");
result.put("flag",false);
ServletUtil.createSuccessResponse(200, result, response);
return;
}
if(StringUtil.isNull(title)){
result.put("message","教程名稱不能爲空!");
result.put("flag",false);
ServletUtil.createSuccessResponse(200, result, response);
return;
}
if(StringUtil.isNull(url)){
result.put("message","地址不能爲空!");
result.put("flag",false);
ServletUtil.createSuccessResponse(200, result, response);
return;
}
learnResouce.setAuthor(author);
learnResouce.setTitle(title);
learnResouce.setUrl(url);
int index=learnService.update(learnResouce);
System.out.println("修改結果="+index);
if(index>0){
result.put("message","教程信息修改爲功!");
result.put("flag",true);
}else{
result.put("message","教程信息修改失敗!");
result.put("flag",false);
}
ServletUtil.createSuccessResponse(200, result, response);
}
/** * 刪除教程 * @param request * @param response */
@RequestMapping(value="/delete",method = RequestMethod.POST)
@ResponseBody
public void deleteUser(HttpServletRequest request ,HttpServletResponse response){
String ids = request.getParameter("ids");
System.out.println("ids==="+ids);
JSONObject result = new JSONObject();
//刪除操做
int index = learnService.deleteByIds(ids.split(","));
if(index>0){
result.put("message","教程信息刪除成功!");
result.put("flag",true);
}else{
result.put("message","教程信息刪除失敗!");
result.put("flag",false);
}
ServletUtil.createSuccessResponse(200, result, response);
}
}複製代碼
package com.dudu.service;
public interface LearnService {
int add(LearnResouce learnResouce);
int update(LearnResouce learnResouce);
int deleteByIds(String[] ids);
LearnResouce queryLearnResouceById(Long learnResouce);
List<LearnResouce> queryLearnResouceList(Map<String, Object> params);
}複製代碼
實現類
package com.dudu.service.impl;
/** * Created by tengj on 2017/4/7. */
@Service
public class LearnServiceImpl implements LearnService {
@Autowired
LearnMapper learnMapper;
@Override
public int add(LearnResouce learnResouce) {
return this.learnMapper.add(learnResouce);
}
@Override
public int update(LearnResouce learnResouce) {
return this.learnMapper.update(learnResouce);
}
@Override
public int deleteByIds(String[] ids) {
return this.learnMapper.deleteByIds(ids);
}
@Override
public LearnResouce queryLearnResouceById(Long id) {
return this.learnMapper.queryLearnResouceById(id);
}
@Override
public List<LearnResouce> queryLearnResouceList(Map<String,Object> params) {
PageHelper.startPage(Integer.parseInt(params.get("page").toString()), Integer.parseInt(params.get("rows").toString()));
return this.learnMapper.queryLearnResouceList(params);
}
}複製代碼
接下來,咱們分別來介紹下註解方式以及XML配置方式。
Mybatis註解的方式好簡單,只要定義一個dao接口,而後sql語句經過註解寫在接口方法上。最後給這個接口添加@Mapper註解或者在啓動類上添加@MapperScan("com.dudu.dao")註解都行。
以下:
package com.dudu.dao;
/** * Created by tengj on 2017/4/22. * Component註解不添加也沒事,只是不加service那邊引入LearnMapper會有錯誤提示,但不影響 */
@Component
@Mapper
public interface LearnMapper {
@Insert("insert into learn_resource(author, title,url) values(#{author},#{title},#{url})")
int add(LearnResouce learnResouce);
@Update("update learn_resource set author=#{author},title=#{title},url=#{url} where id = #{id}")
int update(LearnResouce learnResouce);
@DeleteProvider(type = LearnSqlBuilder.class, method = "deleteByids")
int deleteByIds(@Param("ids") String[] ids);
@Select("select * from learn_resource where id = #{id}")
@Results(id = "learnMap", value = {
@Result(column = "id", property = "id", javaType = Long.class),
@Result(property = "author", column = "author", javaType = String.class),
@Result(property = "title", column = "title", javaType = String.class)
})
LearnResouce queryLearnResouceById(@Param("id") Long id);
@SelectProvider(type = LearnSqlBuilder.class, method = "queryLearnResouceByParams")
List<LearnResouce> queryLearnResouceList(Map<String, Object> params);
class LearnSqlBuilder {
public String queryLearnResouceByParams(final Map<String, Object> params) {
StringBuffer sql =new StringBuffer();
sql.append("select * from learn_resource where 1=1");
if(!StringUtil.isNull((String)params.get("author"))){
sql.append(" and author like '%").append((String)params.get("author")).append("%'");
}
if(!StringUtil.isNull((String)params.get("title"))){
sql.append(" and title like '%").append((String)params.get("title")).append("%'");
}
System.out.println("查詢sql=="+sql.toString());
return sql.toString();
}
//刪除的方法
public String deleteByids(@Param("ids") final String[] ids){
StringBuffer sql =new StringBuffer();
sql.append("DELETE FROM learn_resource WHERE id in(");
for (int i=0;i<ids.length;i++){
if(i==ids.length-1){
sql.append(ids[i]);
}else{
sql.append(ids[i]).append(",");
}
}
sql.append(")");
return sql.toString();
}
}
}複製代碼
須要注意的是,簡單的語句只須要使用@Insert、@Update、@Delete、@Select這4個註解便可,可是有些複雜點須要動態SQL語句,就好比上面方法中根據查詢條件是否有值來動態添加sql的,就須要使用@InsertProvider、@UpdateProvider、@DeleteProvider、@SelectProvider等註解。
這些可選的 SQL 註解容許你指定一個類名和一個方法在執行時來返回運行 容許建立動態 的 SQL。 基於執行的映射語句, MyBatis 會實例化這個類,而後執行由 provider 指定的方法. 該方法能夠有選擇地接受參數對象.(In MyBatis 3.4 or later, it's allow multiple parameters) 屬性: type,method。type 屬性是類。method 屬性是方法名。 注意: 這節以後是對 類的 討論,它能夠幫助你以乾淨,容於閱讀 的方式來構建動態 SQL。
xml配置方式保持映射文件的老傳統,優化主要體如今不須要實現dao的是實現層,系統會自動根據方法名在映射文件中找對應的sql,具體操做以下:
編寫Dao層的代碼
新建LearnMapper接口,無需具體實現類。
package com.dudu.dao;
@Mapper
public interface LearnMapper {
int add(LearnResouce learnResouce);
int update(LearnResouce learnResouce);
int deleteByIds(String[] ids);
LearnResouce queryLearnResouceById(Long id);
public List<LearnResouce> queryLearnResouceList(Map<String, Object> params);
}複製代碼
修改application.properties 配置文件
#指定bean所在包
mybatis.type-aliases-package=com.dudu.domain
#指定映射文件
mybatis.mapperLocations=classpath:mapper/*.xml複製代碼
添加LearnMapper的映射文件
在src/main/resources目錄下新建一個mapper目錄,在mapper目錄下新建LearnMapper.xml文件。
經過mapper標籤中的namespace屬性指定對應的dao映射,這裏指向LearnMapper。
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.dudu.dao.LearnMapper">
<resultMap id="baseResultMap" type="com.dudu.domain.LearnResouce">
<id column="id" property="id" jdbcType="BIGINT" />
<result column="author" property="author" jdbcType="VARCHAR"/>
<result column="title" property="title" jdbcType="VARCHAR"/>
<result column="url" property="url" jdbcType="VARCHAR"/>
</resultMap>
<sql id="baseColumnList" >
id, author, title,url
</sql>
<select id="queryLearnResouceList" resultMap="baseResultMap" parameterType="java.util.HashMap">
select
<include refid="baseColumnList" />
from learn_resource
<where>
1 = 1
<if test="author!= null and author !=''">
AND author like CONCAT(CONCAT('%',#{author,jdbcType=VARCHAR}),'%')
</if>
<if test="title != null and title !=''">
AND title like CONCAT(CONCAT('%',#{title,jdbcType=VARCHAR}),'%')
</if>
</where>
</select>
<select id="queryLearnResouceById" resultMap="baseResultMap" parameterType="java.lang.Long">
SELECT
<include refid="baseColumnList" />
FROM learn_resource
WHERE id = #{id}
</select>
<insert id="add" parameterType="com.dudu.domain.LearnResouce" >
INSERT INTO learn_resource (author, title,url) VALUES (#{author}, #{title}, #{url})
</insert>
<update id="update" parameterType="com.dudu.domain.LearnResouce" >
UPDATE learn_resource SET author = #{author},title = #{title},url = #{url} WHERE id = #{id}
</update>
<delete id="deleteByIds" parameterType="java.lang.String" >
DELETE FROM learn_resource WHERE id in
<foreach item="idItem" collection="array" open="(" separator="," close=")">
#{idItem}
</foreach>
</delete>
</mapper>複製代碼
更多mybatis數據訪問操做的使用請參考:mybatis官方中文參考文檔
上面我有使用到物理分頁插件pagehelper,用法還算簡單,配置以下
pom.xml中添加依賴
<dependency>
<groupId>com.github.pagehelper</groupId>
<artifactId>pagehelper-spring-boot-starter</artifactId>
<version>1.1.0</version>
</dependency>複製代碼
而後你只需在查詢list以前使用PageHelper.startPage(int pageNum, int pageSize)方法便可。pageNum是第幾頁,pageSize是每頁多少條。
@Override
public List<LearnResouce> queryLearnResouceList(Map<String,Object> params) {
PageHelper.startPage(Integer.parseInt(params.get("page").toString()), Integer.parseInt(params.get("rows").toString()));
return this.learnMapper.queryLearnResouceList(params);
}複製代碼
分頁插件PageHelper項目地址: github.com/pagehelper/…
最終項目效果以下,增刪改查分頁一個都很多:
到此爲止,Spring Boot與Mybatis的初步整合就完成了,項目不只整合了bootstrap模板框架,還包含了登陸、攔截器、日誌框架logback等前面介紹的功能。麻雀雖小,五臟俱全。
想要查看更多Spring Boot乾貨教程,可前往:Spring Boot乾貨系列總綱
( ̄︶ ̄)↗[相關示例完整代碼]
想要ace模板源碼的話,在博主公衆號(javaLearn)回覆關鍵字:ace
一直以爲本身寫的不是技術,而是情懷,一篇篇文章是本身這一路走來的痕跡。靠專業技能的成功是最具可複製性的,但願個人這條路能讓你少走彎路,但願我能幫你抹去知識的蒙塵,但願我能幫你理清知識的脈絡,但願將來技術之巔上有你也有我!