由於實習用的是MyBatis框架,因此寫一篇關於SpringBoot整合MyBatis框架的總結。前端
一,Pom文件java
<?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>example</artifactId> <version>1.0-SNAPSHOT</version> <packaging>jar</packaging> //這裏設置爲jar,由於咱們會使用jar包部署運行 <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>1.4.2.RELEASE</version> </parent> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <!-- https://mvnrepository.com/artifact/org.mybatis/mybatis --> <dependency> <groupId>org.mybatis.spring.boot</groupId> <artifactId>mybatis-spring-boot-starter</artifactId> //Mybatis的jar包 <version>1.1.1</version> </dependency> <dependency> <groupId>org.codehaus.jackson</groupId> <artifactId>jackson-mapper-asl</artifactId> //json數據格式和對象的轉換jar包 <version>1.9.8</version> <type>jar</type> <scope>compile</scope> </dependency> <dependency> <groupId>com.h2database</groupId> //內嵌數據庫 <artifactId>h2</artifactId> <version>1.3.156</version> </dependency> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> //lombok插件,方便model對象的處理 <version>1.16.2</version> </dependency> <!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java --> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> //mysql驅動 <version>5.1.18</version> </dependency> </dependencies> <build> <finalName>example</finalName> //打包後的jar包名稱 <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> //必需要的SpringBoot繼承的maven插件,缺乏了沒法打包jar。 <executions> <execution> <goals> <goal>repackage</goal> </goals> </execution> </executions> </plugin> <plugin> <artifactId>maven-resources-plugin</artifactId> //由於jar包中可能存在不少其餘的配置資源,例如mapper文件因此打包爲jar包須要將其加入,因此須要此資源打包插件 <version>2.5</version> <executions> <execution> <id>copy-xmls</id> <phase>process-sources</phase> <goals> <goal>copy-resources</goal> </goals> <configuration> <outputDirectory>${basedir}/target/classes</outputDirectory> <resources> <resource> <directory>${basedir}/src/main/java</directory> <includes> <include>**/*.xml</include> </includes> </resource> </resources> </configuration> </execution> </executions> </plugin> </plugins> <resources> //打包包含相應的資源文件 <resource> <directory>src/main/resources</directory> <includes> <include>**/*.properties</include> <include>**/*.xml</include> <include>**/*.tld</include> </includes> <filtering>false</filtering> </resource> <resource> <directory>src/main/java</directory> <includes> <include>**/*.properties</include> <include>**/*.xml</include> <include>**/*.tld</include> </includes> <filtering>false</filtering> </resource> </resources> </build> <repositories>//設置倉庫 <repository> <id>spring-milestone</id> <url>http://repo.spring.io/libs-release</url> </repository> </repositories> </project>
好了簡單的SpringBoot整合Mybatis框架的基礎環境已經搭建完成了,一個Pom文件搞定,接下來咱們配置咱們的配置文件。mysql
二,配置文件web
咱們寫在resources目錄下的application.properties文件中。ajax
spring.datasource.url=jdbc:mysql://localhost:3306/數據庫名稱?useUnicode=true&characterEncoding=UTF8 spring.datasource.username=用戶名 spring.datasource.password=用戶密碼 spring.datasource.driver-class-name=com.mysql.jdbc.Driver mybatis.mapper-locations=classpath*:/mapper/*Mapper.xml //mapper文件的路徑 mybatis.type-aliases-package=map.model //mapper文件中的前綴 server.port=監聽端口號,不設置默認8080
ok,如今環境已經完全搭建完成咱們能夠編寫本身的代碼了。spring
三,編寫代碼sql
Model對象
數據庫
@Data//@Data lombok插件的註解自動添加get set方法 public class ExampleModel { private Long id; private String name; }
//一個簡單的model對象
Dao層apache
這裏須要注意的是,推薦公司使用的一種作法,由於不少的Dao對象都是簡單的增刪改查功能,因此咱們抽象出一個最基本的父類,這個父類實現最基本的增刪改查功能,每一個新的Dao對象能夠繼承這個類,而後自定義實現特殊的數據庫訪問功能,咱們能夠把這個基本的父類成爲MyBatisHelper並用上泛型,具體實現以下:json
@Data public class MybatisHelper<T> { @Autowired private SqlSession sqlSession; //這裏自動注入mybatis的SqlSession private String nameSpace; public MybatisHelper(String nameSpace) { this.nameSpace = nameSpace; } public String getSqlName(String sqlName) { return nameSpace +"."+ sqlName; } public Integer create(String name, T obj) { return sqlSession.insert(getSqlName(name), obj); } public Boolean update(String name, T obj) { return Boolean.valueOf(sqlSession.update(getSqlName(name), obj) > 0); } public T findById(String name, Long id) { return sqlSession.selectOne(getSqlName(name), id); } public Boolean delete(String name, Long id) { return Boolean.valueOf(sqlSession.delete(getSqlName(name), id) > 0); } public List<T> findAll(String name){return sqlSession.selectList(getSqlName(name));} }
須要說明的是由於sqlSession的執行回去尋找相應的mapper文件,因此namespace+方法名稱很重要,這個必定要注意不要弄錯了,弄錯了就會沒法正確調用。
而後咱們的Dao層實現繼承此類
@Component public class ExampleModelDao extends MybatisHelper<ExampleModel>{ public ExampleModelDao() { super("example.dao."); }
//todo 自定義操做
public Integer findDataCounts(){
return getSqlSession().selectOne(getSqlName("findDataCounts"));//他會尋找example.dao.findDataCounts對應的方法執行
}
}
這樣是否是很簡單,也能大量複用很省事,關於service層我就不寫了很簡單。
四,mapper文件
<?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="example.dao">//這裏很重要就是前綴 <resultMap id="ExampleModelMap" type="ExampleMode"> <id column="id" property="id"/> <result column="name" property="name"/> </resultMap> //自定義resultMap對象,利於對象的操做 <sql id="tb"> //數據表標籤 example_data </sql> <sql id="value_exclude_id"> //除了主鍵覺得的字段集合標籤 name </sql> <sql id="vls"> //插入屬性的字段集合標籤 id,name </sql> <sql id="insert_value">//插入輸入進來的字段值標籤 #{name} </sql> <insert id="create" parameterType="ExampleModel"> INSERT INTO <include refid="tb"/> (<include refid="value_exclude_id"/>) VALUES (<include refid="insert_value"/>) </insert>//一看就明白了建立一個對象 <select id="findById" parameterType="long" resultMap="ExampleModelMap">//返回咱們定義的resultMap SELECT <include refid="vls"/> FROM <include refid="tb"/> WHERE id = #{id} </select> <select id="findAll" resultMap="ExampleModelMap"> SELECT <include refid="vls"/> FROM <include refid="tb"/> </select> <select id="findDataCounts" resultType="int"> SELECT count(1) FROM <include refid="tb"/> </select>//自定義的操做 </mapper>
ok,對應的mapper文件已經有了,咱們就能夠調用了,調用很簡單通常寫在service層中調用,下面咱們去編寫對應的controller。
五,控制器編寫
推薦使用restful風格,所以咱們控制器編寫代碼以下:
@RestController @CrossOrigin //這個是ajax跨域請求容許的註解,不用能夠去掉 public class DigMapDataController { @Autowired private ExampleService exampleService;//service對象 @RequestMapping(value = "/create", method = RequestMethod.POST) public String create(@requestBody ExampleModel exampleModel) { return String.valueOf(exampleService.create(exampleModel)); } //@requestBody註解會接受前端的JSON數據並配合jackson自動轉換爲相應的對象 @RequestMapping(value = "/find/count",method = RequestMethod.GET) public Integer findCounts() { return exampleService.findDataCounts(); } }
一個簡單的控制器就編寫完成了,這個時候咱們能夠啓動應用進行數據訪問了,是否是很簡單。
六,應用的部署
直接在終端中使用命令,將應用打包爲jar文件
1.maven [clean] package ;打包後的文件在target目錄下
2.java -jar example.jar ; 運行咱們的jar包程序
ok 大功告成!
下一章,我會總結一些關於mapper文件的特殊技巧。