SSM No converter found for return value of type

问题原因为  mvc：annotation driven引错了约束

记录下，只需要在开始在初始化时读取springmvc的配置文件即可，不需要错综复杂的操作

    
        dispatcherServlet
        org.springframework.web.servlet.DispatcherServlet
        
            contextConfigLocation
            classpath:application.xml
        
    
    
        dispatcherServlet
        /
    
 
然后Spring部分，搞个配置类，导入mybatis相关的组件
 
 
@ComponentScan(basePackages = "com.sifa")
@Configuration
public class MybatisAndResourceConfig{

    @Bean("datasource")
    public DruidDataSource getDataSource(){
        DruidDataSource dataSource=new DruidDataSource();
        dataSource.setUrl("jdbc:mysql://localhost:3306/test?characterEncoding=utf8");
        dataSource.setUsername("root");
        dataSource.setPassword("123456");
        dataSource.setDriverClassName("com.mysql.jdbc.Driver");
        return dataSource;
    }
    @Bean
    public SqlSessionFactoryBean getSqlSessionFactoryBean(DataSource dataSource){
        SqlSessionFactoryBean sqlSessionFactoryBean=new SqlSessionFactoryBean();
        sqlSessionFactoryBean.setDataSource(dataSource);
        return sqlSessionFactoryBean;
    }
    @Bean
    public MapperScannerConfigurer getMapperScannerConfig(){
        MapperScannerConfigurer mapperScannerConfigurer=new MapperScannerConfigurer();
        mapperScannerConfigurer.setSqlSessionFactoryBeanName("getSqlSessionFactoryBean");
        mapperScannerConfigurer.setbasePackage("com.sifa.dao");
       return mapperScannerConfigurer;
    }

    @Bean
    public DataSourceTransactionManager getDataSourceTransactionManager(DataSource dataSource){
        DataSourceTransactionManager dataSourceTransactionManager=new DataSourceTransactionManager();
        dataSourceTransactionManager.setDataSource(dataSource);
        return  dataSourceTransactionManager;
    }
}