springboot中处理mybatis返回Map时key值的大小写

为了统一不同数据库返回key值大小写不一致的问题，特自定义ObjectWrapperFactory来做统一的处理

1，首先自定义MapWrapper

/**
 * 将Map的key全部转换为小写
 * */
public class MapKeyLowerWrapper extends MapWrapper {

    public MapKeyLowerWrapper(MetaObject metaObject, Map<String, Object> map) {
        super(metaObject, map);
    }
    @Override
    public String findProperty(String name, boolean useCamelCaseMapping) {
        return name==null?"":name.toLowerCase() ;
    }
}

2，自定义ObjectWrapperFactory
mybatis默认的ObjectWrapperFactory

public class DefaultObjectWrapperFactory implements ObjectWrapperFactory {
    public boolean hasWrapperFor(Object object) {
        return false;
    }

    public ObjectWrapper getWrapperFor(MetaObject metaObject, Object object) {
        throw new ReflectionException(
                "The DefaultObjectWrapperFactory should never be called to provide an ObjectWrapper.");
    }
}

我们自定义的如下：

public class MapWrapperFactory implements ObjectWrapperFactory {

    @Override
    public boolean hasWrapperFor(Object object) {
         return object != null && object instanceof Map;
    }

    @Override
    public ObjectWrapper getWrapperFor(MetaObject metaObject, Object object) {
        return new MapKeyLowerWrapper(metaObject, (Map) object);
    }
}

3，在mybatis的配置中添加 MapWrapperFactory 的配置

@Bean(name = "sqlSessionFactory")
@ConditionalOnBean(name = "dataSource")
public SqlSessionFactory sqlSessionFactoryBean(@Qualifier("dataSource") DataSource dataSource) {
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setObjectWrapperFactory(new MapWrapperFactory());
        bean.setDataSource(dataSource);
        // 添加XML目录
        ResourcePatternResolver resolver = new PathMatchingResourcePatternResolver();
        try {
            bean.setMapperLocations(resolver.getResources("classpath*:com/ultrapower/ioss/**/mapper/**/*.xml"));
            return bean.getObject();
        } catch (Exception e) {
            e.printStackTrace();
            throw new RuntimeException(e);
        }
}

@Bean("sqlSessionTemplate")
@ConditionalOnBean(name = "sqlSessionFactory")
public SqlSessionTemplate sqlSessionTemplate(
            @Qualifier("sqlSessionFactory") SqlSessionFactory sqlSessionFactory) {
        return new SqlSessionTemplate(sqlSessionFactory);
}

@ConditionalOnBean(name = "dataSource")
@Bean(name = "transactionManager")
public PlatformTransactionManager transactionManager(@Qualifier("dataSource") DataSource dataSource) {
        DataSourceTransactionManager dataSourceTransactionManager = new DataSourceTransactionManager(dataSource);
        return dataSourceTransactionManager;
}