Mapper代理开发(基于MapperFactoryBean) applicationContext配置 <!-- Mapper代理开发(基于MapperFactoryBean) --> <bean id="customerMapper" class="org.mybatis.spring.mapper.MapperFactoryBean"> <!-- 根据mapperInterface创建 --> <property name="mapperInterface" value="com.POJO.Mapper.CustomerMapper"></property> <!-- 注入sqlSessionFactory --> <property name="sqlSessionFactory" ref="sqlSessionFactory"></property> </bean> mapper文件 <!-- Mapper代理开发的规范 1)Mapper接口的名称和对象的Mapper.xml映射文件中的名称必须一直 2)Mapper.xml文件的namespace与Mapper接口的类路径相同（即接口文件与映射文件需要放在同一个包中） 3）Mapper接口中的方法名和Mappe.xml中定义的每个执行语句的id相同 4)Mapper接口中方法的输入参数类型和Mapper.xml中定义的每个sql的parameterType的类型相同 5）Mapper接口方法的输出参数类型要和Mapper.xml中定义的每个sql的resultType的类型相同 --> <!-- 根据id查询客户信息 --> <select id="findCustomerById" parameterType="Integer" resultType="customer"> select * from t_customer where id = #{id} </select>

MybatisPlus 分页插件 配置 //Spring boot方式 @Configuration @MapperScan("com.baomidou.cloud.service.*.mapper*") public class MybatisPlusConfig { // 旧版 @Bean public PaginationInterceptor paginationInterceptor() { return new PaginationInterceptor(); } // 最新版 @Bean public MybatisPlusInterceptor mybatisPlusInterceptor() { MybatisPlusInterceptor interceptor = new MybatisPlusInterceptor(); interceptor.addInnerInterceptor(new PaginationInnerInterceptor(DbType.H2)); return interceptor; } } 使用

QueryWrapper 常用方法 AbstractWrapper 下的方法及使用 方法名 说明 使用 allEq(Map<R, V> params) 全部 =(或个别 isNull) allEq(params,true) eq = eq("real_name”,"王昭君”) ne <> ne("nick_name”,"空想 4”) gt > gt("age”,21) ge >= ge("age”,22) lt < lt("age”,22) le <= le("age”,21") between cloum between ? and ? between("age”,0,21) notBetween cloum between ? and ? notBetween("age”,0,21) like cloum like '% 王 %’ like("real_name”,"王”) notLike not like '% 王 %’ notLike("real_name”,"王”) likeLeft like '% 王’ likeLeft("real_name”,"昭”) likeRight like '王 %’ likeRight("real_name”,"昭”) isNull is null isNull("gender”) isNotNull is not null isNotNull("gender”) in in (1,2,3) in("nick_name”,lists) notIn age not in (1,2,3) notIn("nick_name”,lists) inSql age in (1,2,3,4,5,6) inSql("nick_name”,"'空想 4’,'空想 5’,'空想 6’") notInSql age not in (1,2,3,4,5,6) notInSql("nick_name”,"'空想 4’,'空想 5’,'空想 6’") groupBy group by id,name groupBy("nick_name”,"age”) orderByAsc order by id ASC,name ASC orderByAsc("nick_name”,"age”) orderByDesc order by id DESC,name DESC orderByDesc("age”) orderBy order by id ASC,name ASC orderBy(true,true,"age”) having having sum(age) > 10 having("sum(age) > 10”) or id = 1 or name = '老王’ eq("nick_name”,"空想 4”).or(i->i.eq("age”,21) eq("nick_name”,"空想 4”).or().eq("nick_name”,"空想 5”) and and (name = '李白’ and status <> '活着’) and(i->i.eq("age”,21)) nested (name = '李白’ and status <> '活着’) nested(i->i.eq("age”,21).eq("nick_name”,"空想 4”)) apply id = 1 apply("nick_name = '空想 4’”) last 最后添加多个以最后的为准，有 sql 注入风险 last("limit 1”) exists 拼接 EXISTS (sql 语句) exists("select id from table where age = 1”) notExists 拼接 NOT EXISTS (sql 语句) notExists("select id from table where age = 1”)

JsonObject json字符串转换成JSonObject对象 字符串： {"code":"1004","msg":"请先添加系统靠勤人员信息！","userRegistInfo":{"acc":"小谷","id":0,"phoneMac":"","phoneNum":"手机号码是：15555215554","phoneSin":"000000000000000","pwd":"e10adc3949ba59abbe56e057f20f883e","registerId":"","status":""}} JSONObject jsonObject = new JSONObject(result); String code = jsonObject.getString("code"); code就是key,获取后就是1004

文件上传 mvc-config.xml <!-- 配置文件上传解析器 id必须是叫multipartResolver--> <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver"> <!-- 设置请求编码格式 --> <property name="defaultEncoding" value="UTF-8" /> /** * 执行文件上传 * @param name * @param uploadfiles * @param file * @return */ @RequestMapping("/fileUpload") public String handlerFormUpload(HttpServletRequest request,String name,@RequestParam("uploadfile") List<MultipartFile> uploadfiles){ //判断所上传文件是否存在 if (!uploadfiles.isEmpty()&&uploadfiles.size()>0) { //循环输出上传的文件 for (MultipartFile file : uploadfiles) { //获取上传文件的原始名称 String originalFilename = file.getOriginalFilename(); //设置上传文件的保存路径 String dirPath=request.getServletContext().getRealPath("/upload/"); File filePath = new File(dirPath); //如果保存文件的地址不存在,就先创建目录 if (!filePath.exists()) { filePath.mkdirs(); } //使用UUID重新命名上传的文件名称(上传人_UUID_原始文件名称) String newFileName=name+"_"+UUID.randomUUID()+"_"+originalFilename; //使用MultipartFile接口的方法完成上传到指定位置 try { file.transferTo(new File(dirPath+newFileName)); System.out.println(dirPath+newFileName); } catch (IllegalStateException | IOException e) { // TODO Auto-generated catch block e.printStackTrace(); return "error"; } } return "success"; }else { return "error"; } }