Spring Boot+mybatis集成数据库访问
1、整合druid数据源
1.1 单数据源配置
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid-spring-boot-starter</artifactId>
<version>1.1.10</version>
</dependency>
@Configuration
public class DruidConfig {
@ConfigurationProperties(prefix = "spring.datasource")
@Bean
public DataSource druid(){
return new DruidDataSource();
}
//配置Druid的监控
//1、配置一个管理后台的Servlet
@Bean
public ServletRegistrationBean statViewServlet(){
ServletRegistrationBean bean = new ServletRegistrationBean(new StatViewServlet(),
"/druid/*");
Map<String,String> initParams = new HashMap<>();
initParams.put("loginUsername","admin");
initParams.put("loginPassword","123456");
initParams.put("allow","");//默认就是允许所有访问
initParams.put("deny","192.168.15.21");
bean.setInitParameters(initParams);
return bean;
}
//2、配置一个web监控的filter
@Bean
public FilterRegistrationBean webStatFilter(){
FilterRegistrationBean bean = new FilterRegistrationBean();
bean.setFilter(new WebStatFilter());
Map<String,String> initParams = new HashMap<>();
initParams.put("exclusions","*.js,*.css,/druid/*");
bean.setInitParameters(initParams);
bean.setUrlPatterns(Arrays.asList("/*"));
return bean;
}
}
spring.datasource.druid.initial-size=10
spring.datasource.druid.min-idle=10
spring.datasource.druid.max-active=15
spring.datasource.druid.filters=stat,wall,log4j2
spring.datasource.druid.filter.config.enabled=true
spring.datasource.druid.filter.stat.enabled=true
spring.datasource.druid.filter.stat.db-type=mysql
spring.datasource.druid.filter.stat.log-slow-sql=true
spring.datasource.druid.filter.stat.slow-sql-millis=2000
spring.datasource.druid.filter.wall.enabled=true
spring.datasource.druid.filter.wall.db-type=mysql
spring.datasource.druid.filter.wall.config.delete-allow=true
spring.datasource.druid.filter.wall.config.drop-table-allow=false
spring.datasource.druid.filter.log4j2.enabled=true
spring.datasource.druid.stat-view-servlet.enabled=true
spring.datasource.druid.stat-view-servlet.url-pattern=/druid/*
spring.datasource.druid.stat-view-servlet.login-username=admin
spring.datasource.druid.stat-view-servlet.login-password=admin@zt3000
spring.datasource.druid.stat-view-servlet.use-global-data-source-stat=true
spring.datasource.druid.web-stat-filter.enabled=true
spring.datasource.druid.web-stat-filter.exclusions=*.js,*.gif,*.jpg,*.png,*.css,*.ico,/druid/*
spring.datasource.druid.aop-patterns=com.xxxxxxxxxxx.bmp.dao.*
spring.datasource.druid.driver-class-name=com.mysql.jdbc.Driver
1.2 多数据源配置
spring:
# 数据源配置
datasource:
ds1: #数据源1
driver-class-name: com.mysql.jdbc.Driver # mysql的驱动你可以配置别的关系型数据库
url: jdbc:mysql://ip:3306/db1 #数据源地址
username: root # 用户名
password: root # 密码
ds2: # 数据源2
driver-class-name: com.mysql.jdbc.Driver # mysql的驱动你可以配置别的关系型数据库
url: jdbc:mysql://ip:3307/db2#数据源地址
username: root # 用户名
password: root # 密码
/**
* 多数据源配置
*/
@Configuration
public class DataSourceConfig {
//主数据源配置 ds1数据源
@Primary
@Bean(name = "ds1DataSourceProperties")
@ConfigurationProperties(prefix = "spring.datasource.ds1")
public DataSourceProperties ds1DataSourceProperties() {
return new DataSourceProperties();
}
//主数据源 ds1数据源
@Primary
@Bean(name = "ds1DataSource")
public DataSource ds1DataSource(@Qualifier("ds1DataSourceProperties") DataSourceProperties dataSourceProperties) {
return dataSourceProperties.initializeDataSourceBuilder().build();
}
//第二个ds2数据源配置
@Bean(name = "ds2DataSourceProperties")
@ConfigurationProperties(prefix = "spring.datasource.ds2")
public DataSourceProperties ds2DataSourceProperties() {
return new DataSourceProperties();
}
//第二个ds2数据源
@Bean("ds2DataSource")
public DataSource ds2DataSource(@Qualifier("ds2DataSourceProperties") DataSourceProperties dataSourceProperties) {
return dataSourceProperties.initializeDataSourceBuilder().build();
}
}
2、整合Mybatis
2.1 简单整合
2.1.1 添加依赖
<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>2.0.0</version>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid-spring-boot-starter</artifactId>
<version>1.1.10</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.28</version>
<scope>runtime</scope>
</dependency>
2.1.2 配置数据源
spring.datasource.url=jdbc:mysql:///testdb?useUnicode=true&characterEncoding=utf-8
spring.datasource.username=root
spring.datasource.password=root
spring.datasource.type=com.alibaba.druid.pool.DruidDataSource
2.1.3 创建Mapper （基于注解）
public interface UserMapper {
@Select("select * from user")
List<User> getAllUsers();
@Results({
@Result(property = "id", column = "id"),
@Result(property = "username", column = "u"),
@Result(property = "address", column = "a")
})
@Select("select username as u,address as a,id as id from user where id=#{id}")
User getUserById(Long id);
@Select("select * from user where username like concat('%',#{name},'%')")
List<User> getUsersByName(String name);
@Insert({"insert into user(username,address) values(#{username},#{address})"})
@SelectKey(statement = "select last_insert_id()", keyProperty = "id", before = false, resultType = Integer.class)
Integer addUser(User user);
@Update("update user set username=#{username},address=#{address} where id=#{id}")
Integer updateUserById(User user);
@Delete("delete from user where id=#{id}")
Integer deleteUserById(Integer id);
}
2.1.4 创建Mapper (基于XML文件)
public interface UserMapper {
List<User> getAllUser();
Integer addUser(User user);
Integer updateUserById(User user);
Integer deleteUserById(Integer id);
}
<?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.boot.mybatis.mapper.UserMapper">
<select id="getAllUser" resultType="org.sang.mybatis.model.User">
select * from t_user;
</select>
<insert id="addUser" parameterType="org.sang.mybatis.model.User">
insert into user (username,address) values (#{username},#{address});
</insert>
<update id="updateUserById" parameterType="org.sang.mybatis.model.User">
update user set username=#{username},address=#{address} where id=#{id}
</update>
<delete id="deleteUserById">
delete from user where id=#{id}
</delete>
</mapper>
2.1.5 Mapper配置文件位置
2.1.5.1 放到UserMapper类同级
必须配置资源插件，因为boot默认只会加载resources的目录文件
<build>
<resources>
<resource>
<directory>src/main/java</directory>
<includes>
<include>**/*.xml</include>
</includes>
</resource>
<resource>
<directory>src/main/resources</directory>
</resource>
</resources>
</build>
2.1.5.1 放到resources文件夹中指定的目录
在application.properties中告诉mybatis去哪里扫描mapper：
mybatis.mapper-locations=classpath:mapper/*.xml
2.2 逆向工程
2.2.1 添加逆向工程插件
<plugin>
<groupId>org.mybatis.generator</groupId>
<artifactId>mybatis-generator-maven-plugin</artifactId>
<version>1.4.0</version>
<configuration>
<configurationFile>src/main/resources/generatorConfig.xml</configurationFile>
<verbose>true</verbose>
<overwrite>true</overwrite>
</configuration>
</plugin>
2.2.2 指定逆向工程配置文件
<?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">
<generatorConfiguration>
<classPathEntry
location="D:\installed\devtools\maven\repository\mysql\mysql-connector-java\5.1.38\mysql-connector-java-5.1.38.jar"/>
<context id="mySQL" targetRuntime="MyBatis3">
<commentGenerator>
<property name="suppressDate" value="true"/>
<property name="suppressAllComments" value="true"/>
</commentGenerator>
<jdbcConnection driverClass="com.mysql.jdbc.Driver"
connectionURL="jdbc:mysql://localhost:3306/2pc" userId="root"
password="123">
</jdbcConnection>
<javaTypeResolver>
<property name="forceBigDecimals" value="false"/>
</javaTypeResolver>
<!--实体生成的配置-->
<javaModelGenerator targetPackage="com.mmren.edu.domain"
targetProject=".\src\main\java">
<property name="enableSubPackages" value="true"/>
<property name="trimStrings" value="true"/>
</javaModelGenerator>
<!--mapper接口生成配置-->
<sqlMapGenerator targetPackage="com.mmren.edu.mapper"
targetProject=".\src\main\java">
<property name="enableSubPackages" value="true"/>
</sqlMapGenerator>
<!--mapper对应的映射文件生成配置-->
<javaClientGenerator type="XMLMAPPER"
targetPackage="com.mmren.edu.mapper" targetProject=".\src\main\java">
<property name="enableSubPackages" value="true"/>
</javaClientGenerator>
<!--表对应实体名称的配置-->
<table tableName="t_order" domainObjectName="OrderInfo"
enableCountByExample="false"
enableUpdateByExample="false"
enableDeleteByExample="false"
enableSelectByExample="false"
selectByExampleQueryId="false"/>
</context>
</generatorConfiguration>
生成实体，mapper，mapper配置文件
2.3 通用Mapper
通用Mapper就是为了解决单表增删改查，基于Mybatis的插件。开发人员不需要编写SQL，不需要在DAO中增加方法，只要写好实体类，就能支持相应的增删改查方法。
2.3.1 添加依赖
<dependency>
<groupId>tk.mybatis</groupId>
<artifactId>mapper-spring-boot-starter</artifactId>
<version>2.1.5</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.38</version>
</dependency>
2.3.2 添加实体
@Table(name="t_user") // 配置实体映射的表名
public class User implements Serializable {
private static final long serialVersionUID = -37900582537861695L;
@Id // 必须配置不配置，如果使用通过ID查询的时候会把所有字段当作条件进行查询
private Integer userId; private String userName; private Integer userAge; private Date userBirth; private Date createTime; private Date updateTime;
public Integer getUserId() {
return userId;
}
public void setUserId(Integer userId) {
this.userId = userId;
}
public String getUserName() {
return userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
public Integer getUserAge() {
return userAge;
}
public void setUserAge(Integer userAge) {
this.userAge = userAge;
}
public Date getUserBirth() {
return userBirth;
}
public void setUserBirth(Date userBirth) {
this.userBirth = userBirth;
}
public Date getCreateTime() {
return createTime;
}
public void setCreateTime(Date createTime) {
this.createTime = createTime;
}
public Date getUpdateTime() {
return updateTime;
}
public void setUpdateTime(Date updateTime) {
this.updateTime = updateTime;
}
}
2.3.3 配置Mapper
@Component
@org.apache.ibatis.annotations.Mapper
public interface UserMapper extends Mapper<User> {
}
2.3.4 配置数据源
spring:
datasource:
driver-class-name: com.mysql.jdbc.Driver
url: jdbc:mysql:///test1?useSSL=false
username: root
password: 123
mybatis:
configuration:
log-impl: org.apache.ibatis.logging.stdout.StdOutImpl
2.3.5 编写测试用例
public class MapperTests extends DemoApplicationTests {
@Autowired
private UserMapper userMapper;
///////////////////////// 查询 测试 /////////////////////
// 测试根据ID查询，必须在注解字段标记@Id
@Test
public void testSelectById() throws Exception {
User user = userMapper.selectByPrimaryKey(30001);
convertToJson(user);
}
// 测试根据指定的列进行查询
@Test
public void testSelectByColumns() throws Exception {
// 创建查询条件对象
Example example = new Example(User.class);
example.and().andEqualTo("userName","牧码人")
.andEqualTo("updateTime","2020-04-21 23:42:13.0");
/* Example.Criteria criteria = example.createCriteria();
criteria.andEqualTo("userName","牧码人")
.andEqualTo("updateTime","2020-04-21 23:42:13.0");*/
User user = userMapper.selectOneByExample(example);
convertToJson(user);
}
// 测试模糊查询后排序
@Test
public void testSelectByColumnsForLike() throws Exception {
// 创建查询条件对象
Example example = new Example(User.class);
example.and().andLike("userName","%人%")
.andBetween("userAge",1,100);
example.orderBy("userId").desc();
/* Example.Criteria criteria = example.createCriteria();
criteria.andEqualTo("userName","牧码人")
.andEqualTo("updateTime","2020-04-21 23:42:13.0");*/
List<User> users = userMapper.selectByExample(example);
convertToJson(users);
}
// 自定义SQL语句查询
@Test
public void testSelectByCustomSql() throws Exception {
// 创建查询条件对象
Example example = new Example(User.class);
example.and().andLike("userName","%人%")
.andBetween("userAge",1,100)
// 自定义拼接的SQL
.andCondition("create_time=","2020-04-22 00:13:58")
// 自定义SQL语句
.andCondition("update_time='2020-04-22 00:13:58'");
example.orderBy("userId").desc();
List<User> users = userMapper.selectByExample(example);
convertToJson(users);
}
// 分页查询(全部)
@Test
public void testSelectByPage() throws Exception {
RowBounds rowBounds = new RowBounds(((1-1)*2),2);
List<User> users = userMapper.selectByRowBounds(new User(), rowBounds);
convertToJson(users);
}
// 分页查询(条件)
@Test
public void testSelectByPageForCondition() throws Exception {
Example example = new Example(User.class);
example.and().andLike("userName","%人%")
.andBetween("userAge",1,100);
example.orderBy("userId").desc();
RowBounds rowBounds = new RowBounds(((1-1)*2),2);
List<User> users = userMapper.selectByExampleAndRowBounds(example, rowBounds);
convertToJson(users);
}
////////////////////////// 添加测试 ////////////////////////
// 插入所有字段
@Value("${random.int[10000,99999]}")
private Integer userId;
@Test
public void testInsert() throws Exception {
User user = new User();
user.setUserAge(30);
user.setUserBirth(new Date());
user.setUserId(40001);
user.setUserName("Gerry");
int row = userMapper.insert(user);
System.out.println(row > 0 ? "成功" : "失败");
}
// 插入选择的字段
@Test
public void testInsertSelective() throws Exception {
User user = new User();
user.setUserAge(30);
user.setUserBirth(new Date());
user.setUserId(userId);
user.setUserName("Gerry");
int row = userMapper.insertSelective(user);
System.out.println(row > 0 ? "成功" : "失败");
}
////////////////////////////// 更新操作 //////////////////////////
// 根据主键更新所有的字段
@Test
public void testUpdateById() throws Exception {
// 根据ID查询信息
User user = new User();
user.setUserId(71636);
user.setUserName("王五11");
int row = userMapper.updateByPrimaryKey(user);
System.out.println(row > 0 ? "成功" : "失败");
}
// 根据主键更新指定的字段
@Test
public void testUpdateSelectiveById() throws Exception {
// 根据ID查询信息
User user = userMapper.selectByPrimaryKey(71636);
user.setUserName("王五");
int row = userMapper.updateByPrimaryKeySelective(user);
System.out.println(row > 0 ? "成功" : "失败");
}
// 根据条件更新所有的字段
@Test
public void testUpdateByExample() throws Exception {
// 创建查询条件对象
Example example = new Example(User.class);
example.and().andEqualTo("userName","牧码人")
.andEqualTo("crateTime","2020-04-21 23:42:13");
int row = userMapper.updateByExample(new User(), example);
System.out.println(row > 0 ? "成功" : "失败");
}
// 根据条件更新指定的字段
@Test
public void testUpdateSelectiveByExample() throws Exception {
// 创建查询条件对象
Example example = new Example(User.class);
example.and().andEqualTo("userName","张三")
.andEqualTo("createTime","2020-04-21 23:41:37");
User user = new User();
user.setUserName("gerry new");
int row = userMapper.updateByExampleSelective(user, example);
System.out.println(row > 0 ? "成功" : "失败");
}
public void convertToJson(Object obj) {
System.out.println("result===>"+JSON.toJSONString(obj, true));
}
///////////////////////////// 测试删除操作
// 根据主键删除记录
@Test
public void testDeleteById() throws Exception {
int row = userMapper.deleteByPrimaryKey(30001);
System.out.println(row > 0 ? "成功" : "失败");
}
// 指定条件删除
@Test
public void testDeleteByExample() throws Exception {
Example example = new Example(User.class);
example.and().andIsNull("userAge");
int row = userMapper.deleteByExample(example);
System.out.println(row > 0 ? "成功" : "失败");
}
// 指定对象删除
@Test
public void testDelete() throws Exception {
User user = new User();
user.setUserName("gerry");
user.setUserId(32118);
int row = userMapper.delete(user);
System.out.println(row > 0 ? "成功" : "失败");
}
}
2.4 Mybatis-Plus
MyBatis-Plus（简称 MP）是一个 MyBatis 的增强工具，在 MyBatis 的基础上只做增强不做改变，为简化开发、提高效率而生。
特性
无侵入：只做增强不做改变，引入它不会对现有工程产生影响，如丝般顺滑；
损耗小：启动即会自动注入基本 CURD，性能基本无损耗，直接面向对象操作；
强大的 CRUD 操作：内置通用 Mapper、通用 Service，仅仅通过少量配置即可实现单表大部分 CRUD 操作，更有强大的条件构造器，满足各类使用需求；
支持 Lambda 形式调用：通过 Lambda 表达式，方便的编写各类查询条件，无需再担心字段写错；
支持主键自动生成：支持多达 4 种主键策略（内含分布式唯一 ID 生成器 - Sequence），可自由配置，完美解决主键问题；
支持 ActiveRecord 模式：支持 ActiveRecord 形式调用，实体类只需继承 Model 类即可进行强大的 CRUD 操作；
支持自定义全局通用操作：支持全局通用方法注入（ Write once, use anywhere ）；
内置代码生成器：采用代码或者 Maven 插件可快速生成 Mapper 、 Model 、 Service 、 Controller 层代码，支持模板引擎，更有超多自定义配置等您来使用；
内置分页插件：基于 MyBatis 物理分页，开发者无需关心具体操作，配置好插件之后，写分页等同于普通 List 查询；
分页插件支持多种数据库：支持 MySQL、MariaDB、Oracle、DB2、H2、HSQL、SQLite、Postgre、SQLServer 等多种数据库；
内置性能分析插件：可输出 Sql 语句以及其执行时间，建议开发测试时启用该功能，能快速揪出慢查询；
内置全局拦截插件：提供全表 delete 、 update 操作智能分析阻断，也可自定义拦截规则，预防误操作。
2.4.1 添加依赖
<!--mybatis-plus依赖-->
<dependency>
<groupId>com.baomidou</groupId>
<artifactId>mybatis-plus-boot-starter</artifactId>
<version>3.3.1</version>
</dependency>
2.4.2 添加实体
public class User implements Serializable {
private static final long serialVersionUID = -37900582537861695L;
private Integer userId;
private String userName;
private Integer userAge;
private Date userBirth;
private Date createTime;
private Date updateTime;
public Integer getUserId() {
return userId;
}
public void setUserId(Integer userId) {
this.userId = userId;
}
public String getUserName() {
return userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
public Integer getUserAge() {
return userAge;
}
public void setUserAge(Integer userAge) {
this.userAge = userAge;
}
public Date getUserBirth() {
return userBirth;
}
public void setUserBirth(Date userBirth) {
this.userBirth = userBirth;
}
public Date getCreateTime() {
return createTime;
}
public void setCreateTime(Date createTime) {
this.createTime = createTime;
}
public Date getUpdateTime() {
return updateTime;
}
public void setUpdateTime(Date updateTime) {
this.updateTime = updateTime;
}
}
2.4.3 添加配置
spring:
datasource:
driver-class-name: com.mysql.cj.jdbc.Driver
url: jdbc:mysql:///test1?useSSL=false&serverTimezone=GMT%2B8
username: root
password: 123
mybatis-plus:
configuration:
log-impl: org.apache.ibatis.logging.stdout.StdOutImpl
map-underscore-to-camel-case: true
2.4.4 配置Mapper
@Mapper
@Component
public interface UserMapper extends BaseMapper<User> { }
2.4.5 配置Service
public interface UserService extends IService<User> {
}
@Service
public class UserServiceImpl extends ServiceImpl<UserMapper, User> implements UserService {
}
启动分页
@Configuration
public class PageConfig {
@Bean
public PaginationInterceptor paginationInterceptor() {
return new PaginationInterceptor();
}
}
2.4.6 编写测试用例
public class MpApplicationTests extends DemoMpApplicationTests {
@Autowired
private UserService userService;
@Value("${random.int[10000,99999]}")
private Integer userId;
@Test
public void testSaveUser() throws Exception {
User user = new User();
user.setUserId(userId);
user.setUserName("MP测试3");
user.setUserAge(20);
user.setUserBirth(new Date());
boolean save = userService.save(user);
System.out.println(save ? "成功" : "失败");
}
@Test
public void testSelectAll() throws Exception {
List<User> list = userService.list();
convertToJson(list);
}
@Test
public void testSelectByCondition() throws Exception {
QueryWrapper<User> userQueryWrapper = new QueryWrapper<>();
//userQueryWrapper.eq("user_name","MP测试1");
userQueryWrapper.lambda().eq(User::getUserName,"Map测试");
List<User> list = userService.list(userQueryWrapper);
convertToJson(list);
}
@Test
public void testSelectByPage() throws Exception {
Page<User> userPage = new Page<>(1, 2);
Page<User> page = userService
.page(userPage,new QueryWrapper<User>().lambda().like(User::getUserName,"测试"));
convertToJson(page);
}
public void convertToJson(Object obj) {
System.out.println("result===>"+ JSON.toJSONString(obj, true));
}
}
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