Spring Boot如何整合mybatisplus
文章目录
- 1. 相关配置和代码
- 2. 整合原理
-
- 2.1 spring boot自动配置
- 2.2 MybatisPlusAutoConfiguration
- 2.3 debug流程
-
- 2.3.1 MapperScannerRegistrar
- 2.3.2MapperScannerConfigurer
- 2.3.3 创建MybatisPlusAutoConfiguration
- 2.3.4 创建sqlSessionFactory
- 2.3.5 创建SqlSessionTemplate
- 2.3.6 mapper接口代理对象创建
1. 相关配置和代码
- maven
<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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0modelVersion>
<parent>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-parentartifactId>
<version>2.7.14version>
<relativePath/>
parent>
<groupId>com.bogegroupId>
<artifactId>mybatisplus-spring-bootartifactId>
<version>0.0.1-SNAPSHOTversion>
<name>mybatis-spring-bootname>
<description>mybatis-spring-bootdescription>
<properties>
<java.version>1.8java.version>
properties>
<dependencies>
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-webartifactId>
dependency>
<dependency>
<groupId>com.baomidougroupId>
<artifactId>mybatis-plus-boot-starterartifactId>
<version>3.5.3.1version>
dependency>
<dependency>
<groupId>com.alibabagroupId>
<artifactId>druid-spring-boot-starterartifactId>
<version>1.2.18version>
dependency>
<dependency>
<groupId>com.mysqlgroupId>
<artifactId>mysql-connector-jartifactId>
<scope>runtimescope>
dependency>
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-testartifactId>
<scope>testscope>
dependency>
<dependency>
<groupId>org.mybatis.spring.bootgroupId>
<artifactId>mybatis-spring-boot-starter-testartifactId>
<version>2.3.1version>
<scope>testscope>
dependency>
<dependency>
<groupId>org.projectlombokgroupId>
<artifactId>lombokartifactId>
<version>1.18.28version>
<scope>providedscope>
dependency>
dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-maven-pluginartifactId>
plugin>
plugins>
build>
project>
- application.yml
server:
port: 8000
spring:
main:
allow-circular-references: true
allow-bean-definition-overriding: true
application:
name: freedom-code
datasource:
type: com.alibaba.druid.pool.DruidDataSource
# MYSQL 5 驱动：com.mysql.jdbc.Driver，MYSQL 6+ 驱动：com.mysql.cj.jdbc.Driver
driver-class-name: com.mysql.jdbc.Driver
url: jdbc:mysql://localhost:3306/mybatis-vip?characterEncoding=utf-8&serverTimezone=UTC
username: root
password: sdfsaxs!
druid:
# 初始化大小，最小，最大
initial-size: 5
min-idle: 5
max-active: 100
# 配置获取连接等待超时的时间
max-wait: 60000
# 配置间隔多久才进行一次检测，检测需要关闭的空闲连接，单位毫秒
time-between-eviction-runs-millis: 60000
# 配置一个连接在池中最小生存时间
min-evictable-idle-time-millis: 300000
validation-query: select VERSION()
test-while-idle: true
test-on-borrow: false
test-on-return: false
# mybatisplus的配置
mybatis-plus:
configuration:
# 是否开启自动驼峰命名规则
map-underscore-to-camel-case: true
# 对所有的 resultMap 都进行自动映射
auto-mapping-behavior: full
# #控制台打印完整带参数SQL语句
log-impl: org.apache.ibatis.logging.stdout.StdOutImpl
mapper-locations: classpath:mapper/**/*.xml
type-aliases-package: "com.boge.pojo"
@Mapper
public interface UserMapper extends BaseMapper<UserDO> {
List<User> query();
}
@Data
@TableName("t_user")
public class UserDO implements Serializable {
@TableId(type = IdType.ASSIGN_ID)
private Integer id;
private String userName;
private String password;
private String realName;
private Integer age;
private Integer dId;
}
@MapperScan("com.boge.mapper")
@SpringBootApplication
public class MybatisSpringBootApplication {
public static void main(String[] args) {
SpringApplication.run(MybatisSpringBootApplication.class, args);
}
}
2. 整合原理
关注三个对象的创建：
- SqlSessionFactory如何创建
- SqlSession如何创建
- Mapper接口的代理类如何创建（比如UserMapper）。
2.1 spring boot自动配置
2.2 MybatisPlusAutoConfiguration
源码
/**
* {@link EnableAutoConfiguration Auto-Configuration} for Mybatis. Contributes a
* {@link SqlSessionFactory} and a {@link SqlSessionTemplate}.
*
* If {@link org.mybatis.spring.annotation.MapperScan} is used, or a
* configuration file is specified as a property, those will be considered,
* otherwise this auto-configuration will attempt to register mappers based on
* the interface definitions in or under the root auto-configuration package.
*
* copy from {@link org.mybatis.spring.boot.autoconfigure.MybatisAutoConfiguration}
*
* @author Eddú Meléndez
* @author Josh Long
* @author Kazuki Shimizu
* @author Eduardo Macarrón
*/
@Configuration(proxyBeanMethods = false)
@ConditionalOnClass({SqlSessionFactory.class, SqlSessionFactoryBean.class})
@ConditionalOnSingleCandidate(DataSource.class)
@EnableConfigurationProperties(MybatisPlusProperties.class)
@AutoConfigureAfter({DataSourceAutoConfiguration.class, MybatisPlusLanguageDriverAutoConfiguration.class})
public class MybatisPlusAutoConfiguration implements InitializingBean {
private static final Logger logger = LoggerFactory.getLogger(MybatisPlusAutoConfiguration.class);
private final MybatisPlusProperties properties;
private final Interceptor[] interceptors;
private final TypeHandler[] typeHandlers;
private final LanguageDriver[] languageDrivers;
private final ResourceLoader resourceLoader;
private final DatabaseIdProvider databaseIdProvider;
private final List<ConfigurationCustomizer> configurationCustomizers;
private final List<SqlSessionFactoryBeanCustomizer> sqlSessionFactoryBeanCustomizers;
private final List<MybatisPlusPropertiesCustomizer> mybatisPlusPropertiesCustomizers;
private final ApplicationContext applicationContext;
public MybatisPlusAutoConfiguration(MybatisPlusProperties properties,
ObjectProvider<Interceptor[]> interceptorsProvider,
ObjectProvider<TypeHandler[]> typeHandlersProvider,
ObjectProvider<LanguageDriver[]> languageDriversProvider,
ResourceLoader resourceLoader,
ObjectProvider<DatabaseIdProvider> databaseIdProvider,
ObjectProvider<List<ConfigurationCustomizer>> configurationCustomizersProvider,
ObjectProvider<List<SqlSessionFactoryBeanCustomizer>> sqlSessionFactoryBeanCustomizers,
ObjectProvider<List<MybatisPlusPropertiesCustomizer>> mybatisPlusPropertiesCustomizerProvider,
ApplicationContext applicationContext) {
this.properties = properties;
this.interceptors = interceptorsProvider.getIfAvailable();
this.typeHandlers = typeHandlersProvider.getIfAvailable();
this.languageDrivers = languageDriversProvider.getIfAvailable();
this.resourceLoader = resourceLoader;
this.databaseIdProvider = databaseIdProvider.getIfAvailable();
this.configurationCustomizers = configurationCustomizersProvider.getIfAvailable();
this.sqlSessionFactoryBeanCustomizers = sqlSessionFactoryBeanCustomizers.getIfAvailable();
this.mybatisPlusPropertiesCustomizers = mybatisPlusPropertiesCustomizerProvider.getIfAvailable();
this.applicationContext = applicationContext;
}
@Override
public void afterPropertiesSet() {
if (!CollectionUtils.isEmpty(mybatisPlusPropertiesCustomizers)) {
mybatisPlusPropertiesCustomizers.forEach(i -> i.customize(properties));
}
checkConfigFileExists();
}
private void checkConfigFileExists() {
if (this.properties.isCheckConfigLocation() && StringUtils.hasText(this.properties.getConfigLocation())) {
Resource resource = this.resourceLoader.getResource(this.properties.getConfigLocation());
Assert.state(resource.exists(),
"Cannot find config location: " + resource + " (please add config file or check your Mybatis configuration)");
}
}
@Bean
@ConditionalOnMissingBean
public SqlSessionFactory sqlSessionFactory(DataSource dataSource) throws Exception {
// TODO 使用 MybatisSqlSessionFactoryBean 而不是 SqlSessionFactoryBean
MybatisSqlSessionFactoryBean factory = new MybatisSqlSessionFactoryBean();
factory.setDataSource(dataSource);
factory.setVfs(SpringBootVFS.class);
if (StringUtils.hasText(this.properties.getConfigLocation())) {
factory.setConfigLocation(this.resourceLoader.getResource(this.properties.getConfigLocation()));
}
applyConfiguration(factory);
if (this.properties.getConfigurationProperties() != null) {
factory.setConfigurationProperties(this.properties.getConfigurationProperties());
}
if (!ObjectUtils.isEmpty(this.interceptors)) {
factory.setPlugins(this.interceptors);
}
if (this.databaseIdProvider != null) {
factory.setDatabaseIdProvider(this.databaseIdProvider);
}
if (StringUtils.hasLength(this.properties.getTypeAliasesPackage())) {
factory.setTypeAliasesPackage(this.properties.getTypeAliasesPackage());
}
if (this.properties.getTypeAliasesSuperType() != null) {
factory.setTypeAliasesSuperType(this.properties.getTypeAliasesSuperType());
}
if (StringUtils.hasLength(this.properties.getTypeHandlersPackage())) {
factory.setTypeHandlersPackage(this.properties.getTypeHandlersPackage());
}
if (!ObjectUtils.isEmpty(this.typeHandlers)) {
factory.setTypeHandlers(this.typeHandlers);
}
if (!ObjectUtils.isEmpty(this.properties.resolveMapperLocations())) {
factory.setMapperLocations(this.properties.resolveMapperLocations());
}
// TODO 修改源码支持定义 TransactionFactory
this.getBeanThen(TransactionFactory.class, factory::setTransactionFactory);
// TODO 对源码做了一定的修改(因为源码适配了老旧的mybatis版本,但我们不需要适配)
Class<? extends LanguageDriver> defaultLanguageDriver = this.properties.getDefaultScriptingLanguageDriver();
if (!ObjectUtils.isEmpty(this.languageDrivers)) {
factory.setScriptingLanguageDrivers(this.languageDrivers);
}
Optional.ofNullable(defaultLanguageDriver).ifPresent(factory::setDefaultScriptingLanguageDriver);
applySqlSessionFactoryBeanCustomizers(factory);
// TODO 此处必为非 NULL
GlobalConfig globalConfig = this.properties.getGlobalConfig();
// TODO 注入填充器
this.getBeanThen(MetaObjectHandler.class, globalConfig::setMetaObjectHandler);
// TODO 注入参与器
this.getBeanThen(PostInitTableInfoHandler.class, globalConfig::setPostInitTableInfoHandler);
// TODO 注入主键生成器
this.getBeansThen(IKeyGenerator.class, i -> globalConfig.getDbConfig().setKeyGenerators(i));
// TODO 注入sql注入器
this.getBeanThen(ISqlInjector.class, globalConfig::setSqlInjector);
// TODO 注入ID生成器
this.getBeanThen(IdentifierGenerator.class, globalConfig::setIdentifierGenerator);
// TODO 设置 GlobalConfig 到 MybatisSqlSessionFactoryBean
factory.setGlobalConfig(globalConfig);
return factory.getObject();
}
/**
* 检查spring容器里是否有对应的bean,有则进行消费
*
* @param clazz class
* @param consumer 消费
* @param 泛型
*/
private <T> void getBeanThen(Class<T> clazz, Consumer<T> consumer) {
if (this.applicationContext.getBeanNamesForType(clazz, false, false).length > 0) {
consumer.accept(this.applicationContext.getBean(clazz));
}
}
/**
* 检查spring容器里是否有对应的bean,有则进行消费
*
* @param clazz class
* @param consumer 消费
* @param 泛型
*/
private <T> void getBeansThen(Class<T> clazz, Consumer<List<T>> consumer) {
if (this.applicationContext.getBeanNamesForType(clazz, false, false).length > 0) {
final Map<String, T> beansOfType = this.applicationContext.getBeansOfType(clazz);
List<T> clazzList = new ArrayList<>();
beansOfType.forEach((k, v) -> clazzList.add(v));
consumer.accept(clazzList);
}
}
// TODO 入参使用 MybatisSqlSessionFactoryBean
private void applyConfiguration(MybatisSqlSessionFactoryBean factory) {
// TODO 使用 MybatisConfiguration
MybatisConfiguration configuration = this.properties.getConfiguration();
if (configuration == null && !StringUtils.hasText(this.properties.getConfigLocation())) {
configuration = new MybatisConfiguration();
}
if (configuration != null && !CollectionUtils.isEmpty(this.configurationCustomizers)) {
for (ConfigurationCustomizer customizer : this.configurationCustomizers) {
customizer.customize(configuration);
}
}
factory.setConfiguration(configuration);
}
private void applySqlSessionFactoryBeanCustomizers(MybatisSqlSessionFactoryBean factory) {
if (!CollectionUtils.isEmpty(this.sqlSessionFactoryBeanCustomizers)) {
for (SqlSessionFactoryBeanCustomizer customizer : this.sqlSessionFactoryBeanCustomizers) {
customizer.customize(factory);
}
}
}
@Bean
@ConditionalOnMissingBean
public SqlSessionTemplate sqlSessionTemplate(SqlSessionFactory sqlSessionFactory) {
ExecutorType executorType = this.properties.getExecutorType();
if (executorType != null) {
return new SqlSessionTemplate(sqlSessionFactory, executorType);
} else {
return new SqlSessionTemplate(sqlSessionFactory);
}
}
/**
* This will just scan the same base package as Spring Boot does. If you want more power, you can explicitly use
* {@link org.mybatis.spring.annotation.MapperScan} but this will get typed mappers working correctly, out-of-the-box,
* similar to using Spring Data JPA repositories.
*/
public static class AutoConfiguredMapperScannerRegistrar
implements BeanFactoryAware, EnvironmentAware, ImportBeanDefinitionRegistrar {
private BeanFactory beanFactory;
private Environment environment;
@Override
public void registerBeanDefinitions(AnnotationMetadata importingClassMetadata, BeanDefinitionRegistry registry) {
if (!AutoConfigurationPackages.has(this.beanFactory)) {
logger.debug("Could not determine auto-configuration package, automatic mapper scanning disabled.");
return;
}
logger.debug("Searching for mappers annotated with @Mapper");
List<String> packages = AutoConfigurationPackages.get(this.beanFactory);
if (logger.isDebugEnabled()) {
packages.forEach(pkg -> logger.debug("Using auto-configuration base package '{}'", pkg));
}
BeanDefinitionBuilder builder = BeanDefinitionBuilder.genericBeanDefinition(MapperScannerConfigurer.class);
builder.addPropertyValue("processPropertyPlaceHolders", true);
builder.addPropertyValue("annotationClass", Mapper.class);
builder.addPropertyValue("basePackage", StringUtils.collectionToCommaDelimitedString(packages));
BeanWrapper beanWrapper = new BeanWrapperImpl(MapperScannerConfigurer.class);
Set<String> propertyNames = Stream.of(beanWrapper.getPropertyDescriptors()).map(PropertyDescriptor::getName)
.collect(Collectors.toSet());
if (propertyNames.contains("lazyInitialization")) {
// Need to mybatis-spring 2.0.2+
// TODO 兼容了mybatis.lazy-initialization配置
builder.addPropertyValue("lazyInitialization", "${mybatis-plus.lazy-initialization:${mybatis.lazy-initialization:false}}");
}
if (propertyNames.contains("defaultScope")) {
// Need to mybatis-spring 2.0.6+
builder.addPropertyValue("defaultScope", "${mybatis-plus.mapper-default-scope:}");
}
// for spring-native
boolean injectSqlSession = environment.getProperty("mybatis.inject-sql-session-on-mapper-scan", Boolean.class,
Boolean.TRUE);
if (injectSqlSession && this.beanFactory instanceof ListableBeanFactory) {
ListableBeanFactory listableBeanFactory = (ListableBeanFactory) this.beanFactory;
Optional<String> sqlSessionTemplateBeanName = Optional
.ofNullable(getBeanNameForType(SqlSessionTemplate.class, listableBeanFactory));
Optional<String> sqlSessionFactoryBeanName = Optional
.ofNullable(getBeanNameForType(SqlSessionFactory.class, listableBeanFactory));
if (sqlSessionTemplateBeanName.isPresent() || !sqlSessionFactoryBeanName.isPresent()) {
builder.addPropertyValue("sqlSessionTemplateBeanName",
sqlSessionTemplateBeanName.orElse("sqlSessionTemplate"));
} else {
builder.addPropertyValue("sqlSessionFactoryBeanName", sqlSessionFactoryBeanName.get());
}
}
builder.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
registry.registerBeanDefinition(MapperScannerConfigurer.class.getName(), builder.getBeanDefinition());
}
@Override
public void setBeanFactory(BeanFactory beanFactory) {
this.beanFactory = beanFactory;
}
@Override
public void setEnvironment(Environment environment) {
this.environment = environment;
}
private String getBeanNameForType(Class<?> type, ListableBeanFactory factory) {
String[] beanNames = factory.getBeanNamesForType(type);
return beanNames.length > 0 ? beanNames[0] : null;
}
}
/**
* If mapper registering configuration or mapper scanning configuration not present, this configuration allow to scan
* mappers based on the same component-scanning path as Spring Boot itself.
*/
@org.springframework.context.annotation.Configuration
@Import(AutoConfiguredMapperScannerRegistrar.class)
@ConditionalOnMissingBean({MapperFactoryBean.class, MapperScannerConfigurer.class})
public static class MapperScannerRegistrarNotFoundConfiguration implements InitializingBean {
@Override
public void afterPropertiesSet() {
logger.debug(
"Not found configuration for registering mapper bean using @MapperScan, MapperFactoryBean and MapperScannerConfigurer.");
}
}
@Order
@Bean
@ConditionalOnMissingBean
public DdlApplicationRunner ddlApplicationRunner(@Autowired(required = false) List<IDdl> ddlList) {
if (ObjectUtils.isEmpty(ddlList)) {
return null;
}
return new DdlApplicationRunner(ddlList);
}
}
2.3 debug流程
2.3.1 MapperScannerRegistrar
主要为MapperScannerConfigurer定制beanDefinition
2.3.2MapperScannerConfigurer
MapperScannerConfigurer实现了BeanDefinitionRegistryPostProcessor。
方法postProcessBeanDefinitionRegistry可以修改beanDefinition信息。为mapper接口定制beanDefinition。
2.3.3 创建MybatisPlusAutoConfiguration
2.3.4 创建sqlSessionFactory
这里用MybatisSqlSessionFactoryBean来创建sqlSessionFactory。
重点看buildSqlSessionFactory方法
2.3.5 创建SqlSessionTemplate
2.3.6 mapper接口代理对象创建
打断点到MybatisMapperRegistry
