Springboot项目之mybatis-plus多容器分布式部署id重复问题之源码解析

mybatis-plus 3.3.2 部署多个pod id冲突问题

配置：

# 设置随机
mybatis-plus.global-config.worker-id: ${random.int(1,31)}
mybatis-plus.global-config.datacenter-id: ${random.int(1,31)}

源码解析：MybatisSqlSessionFactoryBean

重点：new MybatisSqlSessionFactoryBuilder().build(targetConfiguration); -->IdWorker.setIdentifierGenerator(identifierGenerator);

protected SqlSessionFactory buildSqlSessionFactory() throws Exception {final MybatisConfiguration targetConfiguration;// TODO 使用 MybatisXmlConfigBuilder 而不是 XMLConfigBuilderMybatisXMLConfigBuilder xmlConfigBuilder = null;if (this.configuration != null) {targetConfiguration = this.configuration;if (targetConfiguration.getVariables() == null) {targetConfiguration.setVariables(this.configurationProperties);} else if (this.configurationProperties != null) {targetConfiguration.getVariables().putAll(this.configurationProperties);}} else if (this.configLocation != null) {// TODO 使用 MybatisXMLConfigBuilderxmlConfigBuilder = new MybatisXMLConfigBuilder(this.configLocation.getInputStream(), null, this.configurationProperties);targetConfiguration = xmlConfigBuilder.getConfiguration();} else {LOGGER.debug(() -> "Property 'configuration' or 'configLocation' not specified, using default MyBatis Configuration");// TODO 使用 MybatisConfigurationtargetConfiguration = new MybatisConfiguration();Optional.ofNullable(this.configurationProperties).ifPresent(targetConfiguration::setVariables);}// TODO 无配置启动所必须的this.globalConfig = Optional.ofNullable(this.globalConfig).orElseGet(GlobalConfigUtils::defaults);this.globalConfig.setDbConfig(Optional.ofNullable(this.globalConfig.getDbConfig()).orElseGet(GlobalConfig.DbConfig::new));// TODO 初始化 id-work 以及 打印骚东西targetConfiguration.setGlobalConfig(this.globalConfig);// TODO 自定义枚举类扫描处理if (hasLength(this.typeEnumsPackage)) {Set<Class<?>> classes;if (typeEnumsPackage.contains(StringPool.STAR) && !typeEnumsPackage.contains(StringPool.COMMA)&& !typeEnumsPackage.contains(StringPool.SEMICOLON)) {classes = scanClasses(typeEnumsPackage, null);if (classes.isEmpty()) {LOGGER.warn(() -> "Can't find class in '[" + typeEnumsPackage + "]' package. Please check your configuration.");}} else {classes = new HashSet<>();String[] typeEnumsPackageArray = tokenizeToStringArray(this.typeEnumsPackage,ConfigurableApplicationContext.CONFIG_LOCATION_DELIMITERS);Assert.notNull(typeEnumsPackageArray, "not find typeEnumsPackage:" + typeEnumsPackage);Stream.of(typeEnumsPackageArray).forEach(typePackage -> {try {Set<Class<?>> scanTypePackage = scanClasses(typePackage, null);if (scanTypePackage.isEmpty()) {LOGGER.warn(() -> "Can't find class in '[" + typePackage + "]' package. Please check your configuration.");} else {classes.addAll(scanTypePackage);}} catch (IOException e) {throw new MybatisPlusException("Cannot scan class in '[" + typePackage + "]' package", e);}});}// 取得类型转换注册器TypeHandlerRegistry typeHandlerRegistry = targetConfiguration.getTypeHandlerRegistry();classes.stream().filter(Class::isEnum).filter(MybatisEnumTypeHandler::isMpEnums).forEach(cls -> typeHandlerRegistry.register(cls, MybatisEnumTypeHandler.class));}Optional.ofNullable(this.objectFactory).ifPresent(targetConfiguration::setObjectFactory);Optional.ofNullable(this.objectWrapperFactory).ifPresent(targetConfiguration::setObjectWrapperFactory);Optional.ofNullable(this.vfs).ifPresent(targetConfiguration::setVfsImpl);if (hasLength(this.typeAliasesPackage)) {scanClasses(this.typeAliasesPackage, this.typeAliasesSuperType).stream().filter(clazz -> !clazz.isAnonymousClass()).filter(clazz -> !clazz.isInterface()).filter(clazz -> !clazz.isMemberClass()).forEach(targetConfiguration.getTypeAliasRegistry()::registerAlias);}if (!isEmpty(this.typeAliases)) {Stream.of(this.typeAliases).forEach(typeAlias -> {targetConfiguration.getTypeAliasRegistry().registerAlias(typeAlias);LOGGER.debug(() -> "Registered type alias: '" + typeAlias + "'");});}if (!isEmpty(this.plugins)) {Stream.of(this.plugins).forEach(plugin -> {targetConfiguration.addInterceptor(plugin);LOGGER.debug(() -> "Registered plugin: '" + plugin + "'");});}if (hasLength(this.typeHandlersPackage)) {scanClasses(this.typeHandlersPackage, TypeHandler.class).stream().filter(clazz -> !clazz.isAnonymousClass()).filter(clazz -> !clazz.isInterface()).filter(clazz -> !Modifier.isAbstract(clazz.getModifiers())).forEach(targetConfiguration.getTypeHandlerRegistry()::register);}if (!isEmpty(this.typeHandlers)) {Stream.of(this.typeHandlers).forEach(typeHandler -> {targetConfiguration.getTypeHandlerRegistry().register(typeHandler);LOGGER.debug(() -> "Registered type handler: '" + typeHandler + "'");});}if (!isEmpty(this.scriptingLanguageDrivers)) {Stream.of(this.scriptingLanguageDrivers).forEach(languageDriver -> {targetConfiguration.getLanguageRegistry().register(languageDriver);LOGGER.debug(() -> "Registered scripting language driver: '" + languageDriver + "'");});}Optional.ofNullable(this.defaultScriptingLanguageDriver).ifPresent(targetConfiguration::setDefaultScriptingLanguage);if (this.databaseIdProvider != null) {// fix #64 set databaseId before parse mapper xmlstry {targetConfiguration.setDatabaseId(this.databaseIdProvider.getDatabaseId(this.dataSource));} catch (SQLException e) {throw new NestedIOException("Failed getting a databaseId", e);}}Optional.ofNullable(this.cache).ifPresent(targetConfiguration::addCache);if (xmlConfigBuilder != null) {try {xmlConfigBuilder.parse();LOGGER.debug(() -> "Parsed configuration file: '" + this.configLocation + "'");} catch (Exception ex) {throw new NestedIOException("Failed to parse config resource: " + this.configLocation, ex);} finally {ErrorContext.instance().reset();}}targetConfiguration.setEnvironment(new Environment(MybatisSqlSessionFactoryBean.class.getSimpleName(),this.transactionFactory == null ? new SpringManagedTransactionFactory() : this.transactionFactory,this.dataSource));if (this.mapperLocations != null) {if (this.mapperLocations.length == 0) {LOGGER.warn(() -> "Property 'mapperLocations' was specified but matching resources are not found.");} else {for (Resource mapperLocation : this.mapperLocations) {if (mapperLocation == null) {continue;}try {XMLMapperBuilder xmlMapperBuilder = new XMLMapperBuilder(mapperLocation.getInputStream(),targetConfiguration, mapperLocation.toString(), targetConfiguration.getSqlFragments());xmlMapperBuilder.parse();} catch (Exception e) {throw new NestedIOException("Failed to parse mapping resource: '" + mapperLocation + "'", e);} finally {ErrorContext.instance().reset();}LOGGER.debug(() -> "Parsed mapper file: '" + mapperLocation + "'");}}} else {LOGGER.debug(() -> "Property 'mapperLocations' was not specified.");}final SqlSessionFactory sqlSessionFactory = new MybatisSqlSessionFactoryBuilder().build(targetConfiguration);// TODO SqlRunnerSqlHelper.FACTORY = sqlSessionFactory;// TODO 打印骚东西 Bannerif (globalConfig.isBanner()) {System.out.println(" _ _   |_  _ _|_. ___ _ |    _ ");System.out.println("| | |\\/|_)(_| | |_\\  |_)||_|_\\ ");System.out.println("     /               |         ");System.out.println("                        " + MybatisPlusVersion.getVersion() + " ");}return sqlSessionFactory;
}

idworker实战

其中mybatis-plus内置的ImadcnIdentifierGenerator方法，就已经提供了对idworker框架的支持。

升级版本：v3.4.0

  " + MybatisPlusVersion.getVersion() + " ");
}return sqlSessionFactory;

}

# idworker实战其中mybatis-plus内置的`ImadcnIdentifierGenerator`方法，就已经提供了对idworker框架的支持。升级版本：v3.4.0![在这里插入图片描述](https://img-blog.csdnimg.cn/img_convert/6aac34ebf0f36867d15d889d56f55fd7.png)