SpringBoot+Mybatis+MySQL+MAVEN逆向工程實現增刪改查
這兩天簡單學習了下SpringBoot,發現這玩意配置起來是真的方便,相比於SpringMVC+Spring的配置簡直是天堂!!!
當然學習SpringBoot必須要先學會SpringMVC和Spring。
接下來是一個基於SpringBoot+Mybatis+MySQL+MAVEN的在IDEA環境下的簡單的增刪改查
記錄一下自己的學習過程也希望能幫助到需要的人
第一次寫博客有啥不對的地方請多多指教,多謝啦
首先呢是環境的搭建:
選中SpringInitializr
選擇JDK版本以及項目名稱等
選擇Web+JPA+MySQL+Mybatis
最后的項目結構是
首先在MAVEN中導入依賴,我自己用的是Mybatis的逆向工程創建UserMapper和User實體類,所以有generator兩個配置文件
完整的POM配置如下
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.example</groupId>
<artifactId>demo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>demo</name>
<description>Demo project for Spring Boot</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.4.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>10</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>1.3.2</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
<plugin>
<groupId>org.mybatis.generator</groupId>
<artifactId>mybatis-generator-maven-plugin</artifactId>
<version>1.3.5</version>
<!--
<executions>
<execution>
<id>Generate MyBatis Artifacts</id>
<phase>deploy</phase>
<goals> <goal>generate</goal> </goals>
<execution>
</executions>
-->
<configuration>
<configurationFile>src\main\resources\generatorConfig.xml</configurationFile>
<verbose>true</verbose>
<overwrite>true</overwrite>
</configuration>
<dependencies>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>${mysql.version}</version>
</dependency>
</dependencies>
</plugin>
</plugins>
</build>
</project>
導入之后再右下角確定MAVEN下載依賴 然后呢咱們繼續其他的配置
generator.property:
generator.properties
#Mybatis Generator configuration
#dao類和實體類的位置
project=src/main/java
#mapper文件的位置
resources=src/main/resources
#根據數據庫中的表生成對應的pojo類、dao、mapper
jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/user
jdbc.user=root
jdbc.password=123456
配置數據庫的連接 ,將數據庫連接從generatorConfig里面抽取出來 ,這樣做的好處不言而喻啦
接下來是generatorConfig.xml
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE generatorConfiguration PUBLIC "-//mybatis.org//DTD MyBatis Generator Configuration 1.0//EN" "http://mybatis.org/dtd/mybatis-generator-config_1_0.dtd"> <!-- 配置生成器 --> <generatorConfiguration> <!--執行generator插件生成文件的命令: call mvn mybatis-generator:generate -e --> <!-- 引入配置文件 --> <properties resource="generator.properties"/> <!--classPathEntry:數據庫的JDBC驅動,換成你自己的驅動位置 可選 --> <classPathEntry location="C:\Util\MySQL\mysql\mysql-connector-java-5.1.6-bin.jar" /> <!-- 一個數據庫一個context --> <!--defaultModelType="flat" 大數據字段,不分表 --> <context id="MysqlTables" targetRuntime="MyBatis3Simple" defaultModelType="flat"> <!-- 自動識別數據庫關鍵字,默認false,如果設置為true,根據SqlReservedWords中定義的關鍵字列表; 一般保留默認值,遇到數據庫關鍵字(Java關鍵字),使用columnOverride覆蓋 --> <property name="autoDelimitKeywords" value="true" /> <!-- 生成的Java文件的編碼 --> <property name="javaFileEncoding" value="utf-8" /> <!-- beginningDelimiter和endingDelimiter:指明數據庫的用於標記數據庫對象名的符號,比如ORACLE就是雙引號,MYSQL默認是`反引號; --> <property name="beginningDelimiter" value="`" /> <property name="endingDelimiter" value="`" /> <!-- 格式化java代碼 --> <property name="javaFormatter" value="org.mybatis.generator.api.dom.DefaultJavaFormatter"/> <!-- 格式化XML代碼 --> <property name="xmlFormatter" value="org.mybatis.generator.api.dom.DefaultXmlFormatter"/> <plugin type="org.mybatis.generator.plugins.SerializablePlugin" /> <plugin type="org.mybatis.generator.plugins.ToStringPlugin" /> <!-- 注釋 --> <commentGenerator > <property name="suppressAllComments" value="true"/><!-- 是否取消注釋 --> <property name="suppressDate" value="true" /> <!-- 是否生成注釋代時間戳--> </commentGenerator> <!-- jdbc連接 --> <jdbcConnection driverClass="${jdbc.driver}" connectionURL="${jdbc.url}" userId="${jdbc.user}" password="${jdbc.password}" /> <!-- 類型轉換 --> <javaTypeResolver> <!-- 是否使用bigDecimal, false可自動轉化以下類型(Long, Integer, Short, etc.) --> <property name="forceBigDecimals" value="false"/> </javaTypeResolver> <!-- 生成實體類地址 --> <javaModelGenerator targetPackage="com.example.demo.entity" targetProject="${project}" > <property name="enableSubPackages" value="false"/> <property name="trimStrings" value="true"/> </javaModelGenerator> <!-- 生成mapxml文件 --> <sqlMapGenerator targetPackage="mapper" targetProject="${resources}" > <property name="enableSubPackages" value="false" /> </sqlMapGenerator> <!-- 生成mapxml對應client,也就是接口dao --> <javaClientGenerator targetPackage="com.example.demo.dao" targetProject="${project}" type="XMLMAPPER" > <property name="enableSubPackages" value="false" /> </javaClientGenerator> <!-- table可以有多個,每個數據庫中的表都可以寫一個table,tableName表示要匹配的數據庫表,也可以在tableName屬性中通過使用%通配符來匹配所有數據庫表,只有匹配的表才會自動生成文件 --> <table tableName="user" enableCountByExample="true" enableUpdateByExample="true" enableDeleteByExample="true" enableSelectByExample="true" selectByExampleQueryId="true"> <property name="useActualColumnNames" value="false" /> <!-- 數據庫表主鍵 --> <generatedKey column="id" sqlStatement="Mysql" identity="true" /> </table> </context> </generatorConfiguration>
然后找到右邊的Maven Project
運行!
UserMapper , UserMapper.xml , User實體類就會自動幫我們生成
如圖
然后接着配置application.property
jdbc.type=mysql
spring.datasource.url=jdbc:mysql://localhost:3306/user
spring.datasource.username=root
spring.datasource.password=123456
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
接下來按照J2EE的開發方式 創建dao層 , service層 ,control層
結構如上圖所示
再接下來是代碼
UserMapper:
package com.example.demo.dao; import com.example.demo.entity.User; import org.apache.ibatis.annotations.*; import org.springframework.stereotype.Repository; import java.util.List; @Repository @Mapper //不加注解可能出現掃描不到的情況 public interface UserMapper { @Delete("DELETE FROM user WHERE id = #{id}") int deleteByPrimaryKey(Integer id); @Insert("INSERT INTO user (id,username,password,message) values ( #{id},#{username},#{password},#{message})") int insert(User record); @Select("SELECT * FROM user WHERE id = #{id}") User selectByPrimaryKey(Integer id); @Select("SELECT * FROM user ") List<User> selectAll(); @Update("UPDATE user SET id = #{id}, username = #{username}, password = #{password}," + "message = #{message} where id = #{id}") int updateByPrimaryKey(User record); }
我用的是基於注解的方式的SQL語言,這種適合於查詢語句比較簡單一點的,復雜的查詢語句不推薦使用
UserService
package com.example.demo.service; import com.example.demo.entity.User; import java.util.List; /** * author:lrh * Date:2018/8/13 * Time:14:24 */ public interface UserService { public void insert(User user); public void delete(int id); public void update(User user); public User select(int id); public List<User> selectAll(); }
UserServiceImpl
package com.example.demo.service.impl; import com.example.demo.dao.UserMapper; import com.example.demo.entity.User; import com.example.demo.service.UserService; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; import java.util.List; /** * author:lrh * Date:2018/8/13 * Time:14:50 */ @Service public class UserServiceImpl implements UserService { @Autowired private UserMapper userMapper; @Override public void insert(User user) { userMapper.insert(user); } @Override public void delete(int id) { userMapper.deleteByPrimaryKey(id); } @Override public void update(User user) { userMapper.updateByPrimaryKey(user); } @Override public User select(int id) { return userMapper.selectByPrimaryKey(id); } @Override public List<User> selectAll() { return userMapper.selectAll(); } }
Service層沒啥好說的 就是調用DAO層的方法
最后是Control層
UserControl:
package com.example.demo.control; import com.example.demo.entity.User; import com.example.demo.service.UserService; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.web.bind.annotation.PathVariable; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; import java.util.List; /** * author:lrh * Date:2018/8/13 * Time:14:24 */ @RestController public class UserControl { @Autowired private UserService userService; @RequestMapping("/insert") public void insert(User user){ userService.insert(user); } @RequestMapping("/delete/{id}") public void delete(@PathVariable("id") int id){ userService.delete(id); } @RequestMapping("/update") public void update(User user){ userService.update(user); } @RequestMapping("/select/{id}") public User select(@PathVariable("id") int id){ return userService.select(id); } @RequestMapping("/selectAll") public List<User> selectAll(){ return userService.selectAll(); } }
@RequestMapping是SpringMVC里的注解,比如在這個類里面就是當訪問的是/select的URL時
就使用該方法 {}代表是一個占位符
最后打開DemoApplication,這個文件相當於是整個項目的入口
SpringBoot內置了Tomcat所以不需要在做其他的工作
直接啟動main
啟動!
然后打開localhost:8080
大功告成!打完收工! 告辭告辭。。。