un8.15:SpringBoot——集成MyBatis+SpringMVC

我不是女神ヾ 2023-10-11 18:11 26阅读 0赞

今天我给大家分享的是SpringBoot集成mybatis+SpringMVC，所需软件：JDK1.8、IDEA、MYSQL。

一、新建项目，之前的博客中有提到，在这里就不多说了，建好后修改pom.xml文件，如下：

<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>
    	<parent>
    		<groupId>org.springframework.boot</groupId>
    		<artifactId>spring-boot-starter-parent</artifactId>
    		<version>1.5.2.RELEASE</version>
    	</parent>
     
    	<groupId>cn.personal.qin.demo</groupId>
    	<artifactId>springboot_demo</artifactId>
    	<version>0.0.1-SNAPSHOT</version>
    	<packaging>war</packaging>
     
    	<name>springboot</name>
    	<url>http://maven.apache.org</url>
     
    	<properties>
    		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    		
    		<java.version>1.8</java.version>
    	</properties>
     
    	<dependencies>
    		<dependency>
    			<groupId>junit</groupId>
    			<artifactId>junit</artifactId>
    			<scope>test</scope>
    		</dependency>
    		
    		<dependency>
    			<groupId>org.springframework.boot</groupId>
    			<artifactId>spring-boot-starter-web</artifactId>
    		</dependency>
    		
    		<dependency>
    			<groupId>mysql</groupId>
    			<artifactId>mysql-connector-java</artifactId>
    		</dependency>
    		
    		<dependency>
    			<groupId>org.mybatis.spring.boot</groupId>
    			<artifactId>mybatis-spring-boot-starter</artifactId>
    			<version>1.3.2</version>
    		</dependency>
    		<dependency>
    			<groupId>org.mybatis</groupId>
    			<artifactId>mybatis-spring</artifactId>
    			<version>1.3.1</version>
    		</dependency>
    		<dependency>
    			<groupId>org.mybatis</groupId>
    			<artifactId>mybatis</artifactId>
    			<version>3.5.0</version>
    		</dependency>
    		
    		
    		<dependency>
    			<groupId>com.jolbox</groupId>
    			<artifactId>bonecp-spring</artifactId>
    			<version>0.8.0.RELEASE</version>
    		</dependency>
    		
    		<dependency>
    			<groupId>org.springframework</groupId>
    			<artifactId>spring-tx</artifactId>
    		</dependency>
    		<dependency>
    			<groupId>org.springframework</groupId>
    			<artifactId>spring-jdbc</artifactId>
    		</dependency>
    		<dependency>
    			<groupId>org.springframework</groupId>
    			<artifactId>spring-aspects</artifactId>
    		</dependency>
    		
    		<dependency>
    			<groupId>org.apache.tomcat.embed</groupId>
    			<artifactId>tomcat-embed-jasper</artifactId>
    			<scope>provided</scope>
    		</dependency>
    		
    	</dependencies>
     
    	<build>
    		<finalName>${project.artifactId}</finalName>
    		<plugins>
    			
    			<plugin>
    				<groupId>org.apache.maven.plugins</groupId>
    				<artifactId>maven-resources-plugin</artifactId>
    				<configuration>
    					<encoding>UTF-8</encoding>
    				</configuration>
    			</plugin>
    			
    			<plugin>
    				<groupId>org.apache.maven.plugins</groupId>
    				<artifactId>maven-compiler-plugin</artifactId>
    				<configuration>
    					<source>1.7</source>
    					<target>1.7</target>
    					<encoding>UTF-8</encoding>
    				</configuration>
    			</plugin>
    			
    			<plugin>
    				<groupId>org.springframework.boot</groupId>
    				<artifactId>spring-boot-maven-plugin</artifactId>
    			</plugin>
    			
    		</plugins>
    		<pluginManagement>
    			<plugins>
    				
    				<plugin>
    					<groupId>org.apache.tomcat.maven</groupId>
    					<artifactId>tomcat7-maven-plugin</artifactId>
    					<version>2.2</version>
    				</plugin>
    			</plugins>
    		</pluginManagement>
    	</build>
    </project>

二、创建包，创建controller类，如下：

package org.personal.qin.demo;
     
    import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    import org.springframework.context.annotation.Configuration;
    import org.springframework.stereotype.Controller;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.ResponseBody;
     
    @Controller //springmvc的controller控制器
    @SpringBootApplication //springboot核心注解，目的是开启自动配置，scan会自动扫描该类所在的包或者子包
    @Configuration
    public class MainApplication {
     
    	@RequestMapping("hello")
    	@ResponseBody
    	public String hello() {
    		return "hello world！";
    	}
     
    	public static void main(String[] args) {
    		SpringApplication.run(MainApplication.class, args);
        }
    }

通过代码可以发现，hello方法是一个controller方法，我们通过浏览器访问hello就可以访问该controller。由于SpringBoot内置了Tomcat所以Web项目不需要部署，直接运行即可：鼠标右键-->run as-->Java Application

三、测试，网址：[http://127.0.0.1:8080/hello][http_127.0.0.1_8080_hello]

![2021081017561956.png][]

四、将配置文件拷贝到src/main/resources文件夹中。

![20210810185229950.png][]

五、配置mybatis。

1、MyBatis目录配置类Cast，Cast.java类的作用是用于配置MyBatis中配置文件及mapper、pom的位置。

package org.personal.qin.demo.config;
     
    public class Cast {
    	//配置MyBatis
    	public static final String MYBATIS_CONFIG = "classpath:mybatis-config.xml";
    	public static final String PO_PACKAGE = "org.personal.qin.demo.po";
    	public static final String MAPPER_PACKAGE = "org.personal.qin.demo.mapper";
    	public static final String MAPPER_SCANNER = "classpath:config/mapper/*.xml";
     
    }

2、MyBatis加载配置文件及配置数据源MyBatisConfig，MyBatisConfig.java类的作用是加载MyBatis配置文件，并配置数据源。

package org.personal.qin.demo.config;
     
    import javax.sql.DataSource;
     
    import org.apache.ibatis.session.SqlSessionFactory;
    import org.mybatis.spring.SqlSessionFactoryBean;
    import org.mybatis.spring.boot.autoconfigure.SpringBootVFS;
    import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.Configuration;
    import org.springframework.core.io.Resource;
    import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
    import org.springframework.core.io.support.ResourcePatternResolver;
     
    @Configuration
    public class MyBatisConfig {
    	
        /**
         * ConditionalOnMissingBean当容器里没有指定的Bean的情况下创建该对象
         */
        @Bean
        @ConditionalOnMissingBean
        public SqlSessionFactory sqlSessionFactoryBean(DataSource dataSource) throws Exception {
            SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();
            // 设置数据源
            sqlSessionFactoryBean.setDataSource(dataSource);
            // 添加一行如下代码,解决setTypeAliasesPackage别名设置不起作用问题
            sqlSessionFactoryBean.setVfs(SpringBootVFS.class);
            //设置mybatis的主配置文件
            ResourcePatternResolver resourceResolver = new PathMatchingResourcePatternResolver();
    		Resource mybatisConfigXml = resourceResolver.getResource(Cast.MYBATIS_CONFIG);
    		sqlSessionFactoryBean.setConfigLocation(mybatisConfigXml);
    		// 设置别名包
            sqlSessionFactoryBean.setTypeAliasesPackage(Cast.PO_PACKAGE);
            PathMatchingResourcePatternResolver resolver = new PathMatchingResourcePatternResolver();
            sqlSessionFactoryBean.setMapperLocations(resolver.getResources(Cast.MAPPER_SCANNER));
            return sqlSessionFactoryBean.getObject();
        }
     
    }

3、Mapper扫描MapperScannerConfig，MapperScannerConfig.java类的作用是扫描Mapper。

package org.personal.qin.demo.config;
     
    import org.mybatis.spring.mapper.MapperScannerConfigurer;
    import org.springframework.boot.autoconfigure.AutoConfigureAfter;
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.Configuration;
     
    /**
     * 保证在MybatisConfig类实例化后才实例化此方法
     */
    @Configuration
    @AutoConfigureAfter(MyBatisConfig.class)
    public class MapperScannerConfig {
    	
        /**
         * mapper接口的扫描器
         * 
         * @return
         */
        @Bean
        public MapperScannerConfigurer mapperScannerConfigurer() {
            MapperScannerConfigurer mapperScannerConfigurer = new MapperScannerConfigurer();
            mapperScannerConfigurer.setBasePackage(Cast.MAPPER_PACKAGE);
            return mapperScannerConfigurer;
        }
     
    }

五、配置SpringBoot。

BootApplication.java文件的作用是配置SpringBoot，并加载jdbc配置文件，配置数据库及数据库连接池，MainApplication.java提供了main方法，是该程序的入口以供程序运行。

package org.personal.qin.demo.config;
     
    import javax.sql.DataSource;
     
    import com.jolbox.bonecp.BoneCPDataSource;
    import org.springframework.beans.factory.annotation.Value;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    import org.springframework.boot.builder.SpringApplicationBuilder;
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.ComponentScan;
    import org.springframework.context.annotation.Configuration;
    import org.springframework.context.annotation.PropertySource;
     
    /**
     * 配置文件读取和扫描
     */
    @Configuration
    @PropertySource(value = { "classpath:jdbc.properties" })
    @ComponentScan(basePackages = "org.personal.qin.demo")
    @SpringBootApplication
    public class BootApplication {
     
    	@Value("${jdbc.driver}")
    	private String driverClassName; // 数据库驱动
     
    	@Value("${jdbc.url}")
    	private String url; // 相应驱动的jdbcUrl
     
    	@Value("${jdbc.username}")
    	private String username; // 数据库的用户名
     
    	@Value("${jdbc.password}")
    	private String password; // 数据库的密码
    	
    	@Value("${jdbc.period_in_minutes}")
    	private int periodInMinutes; // 检查数据库连接池中空闲连接的间隔时间，单位是分，默认值：240，如果要取消则设置为0
    	
    	@Value("${jdbc.max_age_in_minutes}")
    	private int maxAgeInMinutes; // 连接池中未使用的链接最大存活时间，单位是分，默认值：60，如果要永远存活设置为0
    	
    	@Value("${jdbc.max_connections_per_partition}")
    	private int maxConnectionsPerPartition; // 每个分区最大的连接数
    	
    	@Value("${jdbc.min_connections_per_partition}")
    	private int minConnectionsPerPartition; // 每个分区最小的连接数
     
    	/**
    	 * 配置数据源
    	 * 
    	 * @return
    	 */
    	@Bean(destroyMethod = "close")
    	public DataSource dataSource() {
    		BoneCPDataSource boneCPDataSource = new BoneCPDataSource();
            boneCPDataSource.setDriverClass(driverClassName);
            boneCPDataSource.setJdbcUrl(url);
            boneCPDataSource.setUsername(username);
            boneCPDataSource.setPassword(password);
            boneCPDataSource.setIdleConnectionTestPeriodInMinutes(periodInMinutes);
            boneCPDataSource.setIdleMaxAgeInMinutes(maxAgeInMinutes);
            boneCPDataSource.setMaxConnectionsPerPartition(maxConnectionsPerPartition);
            boneCPDataSource.setMinConnectionsPerPartition(minConnectionsPerPartition);
            return boneCPDataSource;
    	}
     
    	protected SpringApplicationBuilder springApplicationBuilder(SpringApplicationBuilder builder) {
    		return builder.sources(BootApplication.class);
    	}
     
    }

六、开始编写业务层代码Pojo、Mapper、Controller

1、Pojo  
User.java是Pojo

package org.personal.qin.demo.po;
     
    public class User {
     
        private int id;
        private String name;
        private String password;
     
        public int getId() {
            return id;
        }
     
        public void setId(int id) {
            this.id = id;
        }
     
        public String getName() {
            return name;
        }
     
        public void setName(String name) {
            this.name = name;
        }
     
        public String getPassword() {
            return password;
        }
     
        public void setPassword(String password) {
            this.password = password;
        }
     
        @Override
        public String toString() {
            return "【User】: name=" + name + ", password=" + password;
        }
     
    }

2、Mapper  
UserMapper.java是Mapper接口，UserMapper.xml是操作数据库的配置文件。

package org.personal.qin.demo.mapper;
     
    import java.util.List;
     
    import org.personal.qin.demo.po.User;
     
    public interface UserMapper {
     
        /**
         * 获取全部用户
         * 
         * @return
         */
        List<User> listAll();
     
    }
    
    <?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="org.personal.qin.demo.mapper.UserMapper">
        <select id="listAll" resultType="User">
            select * from t_user
        </select>
    </mapper>

3、Controller  
UserController.java是控制器，提供给web访问

package org.personal.qin.demo.controller;
     
    import java.util.List;
     
    import org.personal.qin.demo.mapper.UserMapper;
    import org.personal.qin.demo.po.User;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.stereotype.Controller;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.ResponseBody;
     
    @Controller
    public class UserController {
     
        @Autowired
        private UserMapper mapper;
     
        @RequestMapping("/users")
        @ResponseBody
        public Object getAllUser() {
            List<User> users = mapper.listAll();
            return users;
        }
     
    }

七、浏览器测试，网址：[http://127.0.0.1:8080/users][http_127.0.0.1_8080_users]  
运行MainApplication.java中的main方法  
![20210810191138651.png][]

八、在配置包下添加springMVCconfig。

package org.personal.qin.demo.config;
     
    import java.nio.charset.Charset;
    import java.util.List;
     
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
     
    import org.springframework.context.annotation.Configuration;
    import org.springframework.http.converter.HttpMessageConverter;
    import org.springframework.http.converter.StringHttpMessageConverter;
    import org.springframework.web.servlet.HandlerInterceptor;
    import org.springframework.web.servlet.ModelAndView;
    import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
    import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
     
    @Configuration //申明这是一个配置
    public class SrpingMVCConfig extends WebMvcConfigurerAdapter {
     
    	/**
    	 * 自定义拦截器
    	 */
        @Override
        public void addInterceptors(InterceptorRegistry registry) {
            HandlerInterceptor handlerInterceptor = new HandlerInterceptor() {
                @Override
                public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
                        throws Exception {
                    System.out.println("自定义拦截器............");
                    return true;
                }
                
                @Override
                public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler,
                        ModelAndView modelAndView) throws Exception {
                    
                }
                
                @Override
                public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler,
                        Exception ex) throws Exception {
                }
            };
            registry.addInterceptor(handlerInterceptor).addPathPatterns("/**");
        }
     
        /**
         * 自定义消息转化器的第二种方法
         */
        @Override
        public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
            StringHttpMessageConverter converter  = new StringHttpMessageConverter(Charset.forName("UTF-8"));
            converters.add(converter);
        }
    }

九、测试，运行MainApplication.java中的main方法。

![20210810191138651.png][]

如此，我们便在springboot中集成了mybatis和springVMC，快行动起来试试。

[http_127.0.0.1_8080_hello]: http://127.0.0.1:8080/hello
[2021081017561956.png]: https://img-blog.csdnimg.cn/2021081017561956.png
[20210810185229950.png]: https://img-blog.csdnimg.cn/20210810185229950.png
[http_127.0.0.1_8080_users]: http://127.0.0.1:8080/users
[20210810191138651.png]: https://img-blog.csdnimg.cn/20210810191138651.png