SpringBoot+MyBatis简单数据访问应用的实例代码

<?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> //这里设置为jar,因为我们会使用jar包部署运行  <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数据格式和对象的转换jar包      <version>1.9.8</version>      <type>jar</type>      <scope>compile</scope>    </dependency>    <dependency>      <groupId>com.h2database</groupId> //内嵌数据库      <artifactId>h2</artifactId>       <version>1.3.156</version>    </dependency>    <dependency>      <groupId>org.projectlombok</groupId>      <artifactId>lombok</artifactId> //lombok插件,方便model对象的处理      <version>1.16.2</version>    </dependency>    <!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java -->    <dependency>      <groupId>mysql</groupId>      <artifactId>mysql-connector-java</artifactId> //mysql驱动      <version>5.1.18</version>    </dependency>  </dependencies>  <build>    <finalName>example</finalName> //打包后的jar包名称    <plugins>      <plugin>        <groupId>org.springframework.boot</groupId>        <artifactId>spring-boot-maven-plugin</artifactId> //必须要的SpringBoot继承的maven插件，缺少了无法打包jar。        <executions>          <execution>            <goals>              <goal>repackage</goal>            </goals>          </execution>        </executions>      </plugin>      <plugin>        <artifactId>maven-resources-plugin</artifactId> //因为jar包中可能存在很多其他的配置资源,例如mapper文件所以打包为jar包需要将其加入，所以需要此资源打包插件        <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> //打包包含相应的资源文件      <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>//设置仓库    <repository>      <id>spring-milestone</id>      <url>http://repo.spring.io/libs-release</url>    </repository>  </repositories></project>

spring.datasource.url=jdbc:mysql://localhost:3306/数据库名称?useUnicode=true&characterEncoding=UTF8spring.datasource.username=用户名spring.datasource.password=用户密码spring.datasource.driver-class-name=com.mysql.jdbc.Drivermybatis.mapper-locations=classpath*:/mapper/*Mapper.xml //mapper文件的路径mybatis.type-aliases-package=map.model //mapper文件中的前缀server.port=监听端口号,不设置默认8080

@Data//@Data lombok插件的注解自动添加get set方法public class ExampleModel {  private Long id;  private String name;}//一个简单的model对象

@Datapublic class MybatisHelper<T> {  @Autowired  private SqlSession sqlSession; //这里自动注入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));}}

@Componentpublic class ExampleModelDao extends MybatisHelper<ExampleModel>{  public ExampleModelDao() {    super("example.dao.");  }//todo 自定义操作public Integer findDataCounts(){  return getSqlSession().selectOne(getSqlName("findDataCounts"));//他会寻找example.dao.findDataCounts对应的方法执行}}

<?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">//这里很重要就是前缀  <resultMap id="ExampleModelMap" type="ExampleMode">    <id column="id" property="id"/>    <result column="name" property="name"/>  </resultMap> //自定义resultMap对象,利于对象的操作  <sql id="tb"> //数据表标签    example_data  </sql>  <sql id="value_exclude_id"> //除了主键以为的字段集合标签    name  </sql>  <sql id="vls"> //插入属性的字段集合标签    id,name  </sql>  <sql id="insert_value">//插入输入进来的字段值标签    #{name}  </sql>  <insert id="create" parameterType="ExampleModel">    INSERT INTO <include refid="tb"/> (<include refid="value_exclude_id"/>) VALUES (<include refid="insert_value"/>)  </insert>//一看就明白了创建一个对象  <select id="findById" parameterType="long" resultMap="ExampleModelMap">//返回我们定义的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>//自定义的操作</mapper>

@RestController@CrossOrigin //这个是ajax跨域请求允许的注解，不用可以去掉public class DigMapDataController {  @Autowired  private ExampleService exampleService;//service对象  @RequestMapping(value = "/create", method = RequestMethod.POST)  public String create(@requestBody ExampleModel exampleModel) {    return String.valueOf(exampleService.create(exampleModel));}//@requestBody注解会接受前端的JSON数据并配合jackson自动转换为相应的对象  @RequestMapping(value = "/find/count",method = RequestMethod.GET)  public Integer findCounts() {    return exampleService.findDataCounts();  }}