问题描述

当使用Mybatis 进行Page分页，再使用Page< map >作为接受参数。此时尝试修改map则会报错。
报错为

java.lang.UnsupportedOperationException: A TupleBackedMap cannot be modified

解决方案

使用新的数组，使用反射，构建工具类，自动将原值拷贝到对应的类上，完成转换。直接上代码

/*** 用于解决mybatis 查询List<map>后无法修改的问题* @author hh* @date 2023/8/3*/
public class MybatisMapUpdateUtils {public static void main(String[] args) throws Exception {Map<String,Object> map  = new HashMap<>();map.put("userName","吉吉强");List<Map<String,Object>>list = new ArrayList<>();list.add(map);List<UserDto> object = (List<UserDto>) getObject(list, UserDto.class);System.out.println(object);}public static Object getObject(List<Map<String,Object>>map, Class className) throws Exception {List<Object> arrayList = new ArrayList<>();for (Map<String,Object> vo: map){Constructor constructors = className.getConstructor();Object instance = constructors.newInstance();for (String key:vo.keySet()){System.out.println("key=  "+key+"   and value=  "+vo.get(key));try {Field field = className.getDeclaredField(key);field.setAccessible(true);field.set(instance,vo.get(key));} catch (Exception e){System.out.println("field not found");}}arrayList.add(instance);}return  arrayList;}}

测试打印后，结果正常

key=  userName   and value=  吉吉强
[UserDto(userName=吉吉强)]进程已结束,退出代码0