Mybatis自定义数据类型处理TypeHandler

mybatis依赖

<dependency>
    <groupId>org.mybatis.spring.boot</groupId>
    <artifactId>mybatis-spring-boot-starter</artifactId>
    <version>${mybatis.spring.boot.starter}</version>
</dependency>
<!-- 翻页插件,自动配置 -->
<dependency>
    <groupId>com.github.pagehelper</groupId>
    <artifactId>pagehelper-spring-boot-starter</artifactId>
    <version>${pagehelper.version}</version>
</dependency>
<!-- oracle驱动 -->
<dependency>
    <groupId>com.oracle.database.jdbc</groupId>
    <artifactId>ojdbc11</artifactId>
</dependency>
<dependency>
    <groupId>com.oracle.database.nls</groupId>
    <artifactId>orai18n</artifactId>
</dependency>
<!-- mysql驱动 -->
<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
</dependency>

在我们application.properties文件中配置mybatis.type-handlers-package=com.xxx.xxx,com.xxx.xxx是typeHandlers的包名

mybatis.type-handlers-package=cn.shhuifu.quickframework.boot.datasource.typeHandler

在此路径下创建处理类OracleTimestampHandler把oracle.sql.TIMESTAMP转为java.sql.Timestmap

package cn.shhuifu.quickframework.boot.datasource.typeHandler;

import oracle.sql.TIMESTAMP;
import org.apache.ibatis.type.BaseTypeHandler;
import org.apache.ibatis.type.JdbcType;
import org.apache.ibatis.type.MappedJdbcTypes;
import org.apache.ibatis.type.MappedTypes;

import java.sql.*;

/**
 * @ClassName OracleTimestampHandler
 * @Description TIMESTAMP自动转换类型
 * @Author LiuQian
 * @Date 2022-11-13
 **/
@MappedJdbcTypes(JdbcType.TIMESTAMP)
@MappedTypes(TIMESTAMP.class)
public class OracleTimestampHandler extends BaseTypeHandler<Timestamp> {

    @Override
    public void setNonNullParameter(PreparedStatement preparedStatement, int i, Timestamp timestamp, JdbcType jdbcType) throws SQLException {
        preparedStatement.setTimestamp(i, timestamp);
    }

    @Override
    public Timestamp getNullableResult(ResultSet resultSet, String s) throws SQLException {
        return parse2time(resultSet.getObject(s));
    }

    @Override
    public Timestamp getNullableResult(ResultSet resultSet, int i) throws SQLException {
        return parse2time(resultSet.getObject(i));
    }

    @Override
    public Timestamp getNullableResult(CallableStatement callableStatement, int i) throws SQLException {
        return parse2time(callableStatement.getObject(i));
    }

    private Timestamp parse2time(Object value) {
        if (value instanceof Date) {
            return new Timestamp(((Date) value).getTime());
        } else if (value instanceof Time) {
            return new Timestamp(((Time) value).getTime());
        } else if (value instanceof Timestamp) {
            return (Timestamp) value;
        } else if(value instanceof TIMESTAMP){
            try {
                return ((TIMESTAMP)value).timestampValue();
            } catch (SQLException throwables) {
                return null;
            }
        }
        return null;
    }
}

其实主要通过MybatisAutoConfiguration自动配置类的方式让SqlSessionFactory在初始化的时候指定包路径，该类内部会引用环境变量MybatisProperties，

@Configuration
@ConditionalOnClass({SqlSessionFactory.class, SqlSessionFactoryBean.class})
@ConditionalOnSingleCandidate(DataSource.class)
@EnableConfigurationProperties({MybatisProperties.class})
@AutoConfigureAfter({DataSourceAutoConfiguration.class, MybatisLanguageDriverAutoConfiguration.class})
public class MybatisAutoConfiguration implements InitializingBean {
    private static final Logger logger = LoggerFactory.getLogger(MybatisAutoConfiguration.class);
    private final MybatisProperties 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;

    public MybatisAutoConfiguration(MybatisProperties properties, ObjectProvider<Interceptor[]> interceptorsProvider, ObjectProvider<TypeHandler[]> typeHandlersProvider, ObjectProvider<LanguageDriver[]> languageDriversProvider, ResourceLoader resourceLoader, ObjectProvider<DatabaseIdProvider> databaseIdProvider, ObjectProvider<List<ConfigurationCustomizer>> configurationCustomizersProvider, ObjectProvider<List<SqlSessionFactoryBeanCustomizer>> sqlSessionFactoryBeanCustomizers) {
        this.properties = properties;
        this.interceptors = (Interceptor[])interceptorsProvider.getIfAvailable();
        this.typeHandlers = (TypeHandler[])typeHandlersProvider.getIfAvailable();
        this.languageDrivers = (LanguageDriver[])languageDriversProvider.getIfAvailable();
        this.resourceLoader = resourceLoader;
        this.databaseIdProvider = (DatabaseIdProvider)databaseIdProvider.getIfAvailable();
        this.configurationCustomizers = (List)configurationCustomizersProvider.getIfAvailable();
        this.sqlSessionFactoryBeanCustomizers = (List)sqlSessionFactoryBeanCustomizers.getIfAvailable();
    }

    public void afterPropertiesSet() {
        this.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 {
        SqlSessionFactoryBean factory = new SqlSessionFactoryBean();
        factory.setDataSource(dataSource);
        factory.setVfs(SpringBootVFS.class);
        if (StringUtils.hasText(this.properties.getConfigLocation())) {
            factory.setConfigLocation(this.resourceLoader.getResource(this.properties.getConfigLocation()));
        }

        this.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());
        }

        Set<String> factoryPropertyNames = (Set)Stream.of((new BeanWrapperImpl(SqlSessionFactoryBean.class)).getPropertyDescriptors()).map(FeatureDescriptor::getName).collect(Collectors.toSet());
        Class<? extends LanguageDriver> defaultLanguageDriver = this.properties.getDefaultScriptingLanguageDriver();
        if (factoryPropertyNames.contains("scriptingLanguageDrivers") && !ObjectUtils.isEmpty(this.languageDrivers)) {
            factory.setScriptingLanguageDrivers(this.languageDrivers);
            if (defaultLanguageDriver == null && this.languageDrivers.length == 1) {
                defaultLanguageDriver = this.languageDrivers[0].getClass();
            }
        }

        if (factoryPropertyNames.contains("defaultScriptingLanguageDriver")) {
            factory.setDefaultScriptingLanguageDriver(defaultLanguageDriver);
        }

        this.applySqlSessionFactoryBeanCustomizers(factory);
        return factory.getObject();
    }

    private void applyConfiguration(SqlSessionFactoryBean factory) {
        org.apache.ibatis.session.Configuration configuration = this.properties.getConfiguration();
        if (configuration == null && !StringUtils.hasText(this.properties.getConfigLocation())) {
            configuration = new org.apache.ibatis.session.Configuration();
        }

        if (configuration != null && !CollectionUtils.isEmpty(this.configurationCustomizers)) {
            Iterator var3 = this.configurationCustomizers.iterator();

            while(var3.hasNext()) {
                ConfigurationCustomizer customizer = (ConfigurationCustomizer)var3.next();
                customizer.customize(configuration);
            }
        }

        factory.setConfiguration(configuration);
    }

    private void applySqlSessionFactoryBeanCustomizers(SqlSessionFactoryBean factory) {
        if (!CollectionUtils.isEmpty(this.sqlSessionFactoryBeanCustomizers)) {
            Iterator var2 = this.sqlSessionFactoryBeanCustomizers.iterator();

            while(var2.hasNext()) {
                SqlSessionFactoryBeanCustomizer customizer = (SqlSessionFactoryBeanCustomizer)var2.next();
                customizer.customize(factory);
            }
        }

    }

    @Bean
    @ConditionalOnMissingBean
    public SqlSessionTemplate sqlSessionTemplate(SqlSessionFactory sqlSessionFactory) {
        ExecutorType executorType = this.properties.getExecutorType();
        return executorType != null ? new SqlSessionTemplate(sqlSessionFactory, executorType) : new SqlSessionTemplate(sqlSessionFactory);
    }

    @Configuration
    @Import({MybatisAutoConfiguration.AutoConfiguredMapperScannerRegistrar.class})
    @ConditionalOnMissingBean({MapperFactoryBean.class, MapperScannerConfigurer.class})
    public static class MapperScannerRegistrarNotFoundConfiguration implements InitializingBean {
        public MapperScannerRegistrarNotFoundConfiguration() {
        }

        public void afterPropertiesSet() {
            MybatisAutoConfiguration.logger.debug("Not found configuration for registering mapper bean using @MapperScan, MapperFactoryBean and MapperScannerConfigurer.");
        }
    }

    public static class AutoConfiguredMapperScannerRegistrar implements BeanFactoryAware, EnvironmentAware, ImportBeanDefinitionRegistrar {
        private BeanFactory beanFactory;
        private Environment environment;

        public AutoConfiguredMapperScannerRegistrar() {
        }

        public void registerBeanDefinitions(AnnotationMetadata importingClassMetadata, BeanDefinitionRegistry registry) {
            if (!AutoConfigurationPackages.has(this.beanFactory)) {
                MybatisAutoConfiguration.logger.debug("Could not determine auto-configuration package, automatic mapper scanning disabled.");
            } else {
                MybatisAutoConfiguration.logger.debug("Searching for mappers annotated with @Mapper");
                List<String> packages = AutoConfigurationPackages.get(this.beanFactory);
                if (MybatisAutoConfiguration.logger.isDebugEnabled()) {
                    packages.forEach((pkg) -> {
                        MybatisAutoConfiguration.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 = (Set)Stream.of(beanWrapper.getPropertyDescriptors()).map(FeatureDescriptor::getName).collect(Collectors.toSet());
                if (propertyNames.contains("lazyInitialization")) {
                    builder.addPropertyValue("lazyInitialization", "${mybatis.lazy-initialization:false}");
                }

                if (propertyNames.contains("defaultScope")) {
                    builder.addPropertyValue("defaultScope", "${mybatis.mapper-default-scope:}");
                }

                boolean injectSqlSession = (Boolean)this.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(this.getBeanNameForType(SqlSessionTemplate.class, listableBeanFactory));
                    Optional<String> sqlSessionFactoryBeanName = Optional.ofNullable(this.getBeanNameForType(SqlSessionFactory.class, listableBeanFactory));
                    if (!sqlSessionTemplateBeanName.isPresent() && sqlSessionFactoryBeanName.isPresent()) {
                        builder.addPropertyValue("sqlSessionFactoryBeanName", sqlSessionFactoryBeanName.get());
                    } else {
                        builder.addPropertyValue("sqlSessionTemplateBeanName", sqlSessionTemplateBeanName.orElse("sqlSessionTemplate"));
                    }
                }

                builder.setRole(2);
                registry.registerBeanDefinition(MapperScannerConfigurer.class.getName(), builder.getBeanDefinition());
            }
        }

        public void setBeanFactory(BeanFactory beanFactory) {
            this.beanFactory = beanFactory;
        }

        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;
        }
    }
}