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1. 基本 CRUD 方法实现：
package com.xxx.xxx.ls.xxx.utils;import com.alibaba.fastjson.JSON;import mon.collect.ImmutableMap;import com.xxx.xxx.ls.xxx.dto.LSResultDTO;import com.xxx.xxx.ls.xxx.model.BaseModel;import com.xxx.xxx.ls.xxx.dto.BaseDTO;import com.xxx.xxx.ls.xxx.dto.LSExceptionResultDTO;import com.xxx.xxx.ls.xxx.enums.ResponseStatusEnum;import com.xxx.xxx.ls.xxx.exceptions.InstitutionException;import com.xxx.xxx.ls.xxx.model.BaseInfo;import lombok.extern.slf4j.Slf4j;import mons.lang3.StringUtils;import org.mon.util.CollectionUtils;import tk.mon.Mapper;import tk.mybatis.mapper.entity.Example;import java.util.Date;import java.util.List;@Slf4jpublic class BaseMethodUtils {/*** 根据id查询数据** @param id* @param tClass* @param mapper* @param <T>* @param <E>* @return*/public static <T, E> LSResultDTO<T> queryById(String id, Class<T> tClass, Mapper<E> mapper) {log.info("根据id查询:{}", id);if (StringUtils.isBlank(id)) {return LSExceptionResultDTO.fail(ResponseStatusEnum.PARAMETERS_ERROR);}try {E e = mapper.selectByPrimaryKey(id);log.info("查询的信息:{}", JSON.toJSONString(e));T t = JSON.parseObject(JSON.toJSONString(e), tClass);if (t == null) {return LSExceptionResultDTO.fail(ResponseStatusEnum.WRONG_CONFIGURATION);}return LSResultDTO.ok(t);} catch (Exception e) {return LSExceptionResultDTO.fail(ResponseStatusEnum.EXEC_FAILURE);}}/*** 查数据列表** @param tClass* @param mapper* @param <T>* @param <E>* @return*/public static <T, E> List<T> queryAll(Class<T> tClass, Mapper<E> mapper) {List<E> infoList = mapper.selectAll();return JsonTransUtils.list2OtherList(infoList, tClass);}/*** 根据条件查数据列表,条件为“等于”** @param tClass* @param eClass* @param map 封装条件* @param mapper* @param <T>* @param <E>* @return*/public static <T, E> List<T> queryAll(Class<T> tClass, Class<E> eClass, ImmutableMap<String, Object> map, Mapper<E> mapper) {Example e = new Example(eClass);Example.Criteria criteria = e.createCriteria();map.forEach(criteria::andEqualTo);List<E> infoList = mapper.selectByExample(e);return JsonTransUtils.list2OtherList(infoList, tClass);}/*** 根据条件查单条数据** @param queryModel* @param tClass返回类对象* @param eClass数据库映射类对象* @param mapper* @param <T>* @param <E>* @return*/public static <T, E> T queryOne(BaseModel queryModel, Class<T> tClass, Class<E> eClass, Mapper<E> mapper) {log.info("根据条件查询一条,参数query:{}", JSON.toJSONString(queryModel));if (queryModel == null) {throw new InstitutionException(400, "请求参数有误");}E e = JSON.parseObject(JSON.toJSONString(queryModel), eClass);E returnInfo = null;try {returnInfo = mapper.selectOne(e);} catch (Exception e1) {throw new InstitutionException(500, "执行异常,数据库可能存在多个相同条件的数据");}if (returnInfo == null) {log.error("没找到该条件的配置信息");throw new InstitutionException(404, "该条件的配置不存在");}return JSON.parseObject(JSON.toJSONString(returnInfo), tClass);}/*** 根据条件查询列表** @param queryModel* @param eClass映射类对象* @param tClass返回类对象* @param mapper* @param <T>* @param <E>* @return*/public static <T, E> List<T> queryListByWhere(BaseModel queryModel, Class<E> eClass, Class<T> tClass, Mapper<E> mapper) {log.info("根据条件查询,参数AppQuery:{}", JSON.toJSONString(queryModel));if (queryModel == null) {throw new InstitutionException(400, "请求参数有误");}E e = JSON.parseObject(JSON.toJSONString(queryModel), eClass);List<E> infoList = mapper.select(e);if (CollectionUtils.isEmpty(infoList)) {log.error("没找到该条件的配置信息");throw new InstitutionException(404, "该条件的配置不存在");}return JsonTransUtils.list2OtherList(infoList, tClass);}/*** 保存** @param baseDTO* @param eClass 映射类对象* @param mapper* @param <E>* @return*/public static <E extends BaseInfo> String save(BaseDTO baseDTO, Class<E> eClass, Mapper<E> mapper) {log.info("保存DTO:{}", JSON.toJSONString(baseDTO));if (baseDTO == null) {throw new InstitutionException(400, "请求参数异常");}try {E e = JSON.parseObject(JSON.toJSONString(baseDTO), eClass);e.setGmtCreate(new Date());e.setGmtUpdate(new Date());e.setUserCreate(baseDTO.getUserCreate());e.setUserUpdate(baseDTO.getUserCreate());mapper.insert(e);return e.getId();} catch (Exception e) {throw new InstitutionException(500, "保存失败");}}/*** 保存,null值取数据库默认值** @param baseDTO* @param eClass 映射类对象* @param mapper* @param <E>* @return*/public static <E extends BaseInfo> String saveSelective(BaseDTO baseDTO, Class<E> eClass, Mapper<E> mapper) {log.info("保存DTO:{}", JSON.toJSONString(baseDTO));if (baseDTO == null) {throw new InstitutionException(400, "请求参数异常");}try {E e = JSON.parseObject(JSON.toJSONString(baseDTO), eClass);e.setGmtCreate(new Date());e.setGmtUpdate(new Date());e.setUserCreate(baseDTO.getUserCreate());e.setUserUpdate(baseDTO.getUserCreate());mapper.insertSelective(e);return e.getId();} catch (Exception e) {throw new InstitutionException(500, "保存失败");}}/*** 更新** @param baseDTO* @param eClass* @param mapper* @param <E>* @return*/public static <E extends BaseInfo> Integer update(BaseDTO baseDTO, Class<E> eClass, Mapper<E> mapper) {log.info("更新AppDTO:{}", JSON.toJSONString(baseDTO));if (baseDTO == null) {throw new InstitutionException(400, "请求参数异常");}if (StringUtils.isBlank(baseDTO.getId())) {throw new InstitutionException(400, "id不能为空");}try {E e = JSON.parseObject(JSON.toJSONString(baseDTO), eClass);e.setGmtUpdate(new Date());e.setUserUpdate(baseDTO.getUserUpdate());return mapper.updateByPrimaryKey(e);} catch (Exception e) {throw new InstitutionException(500, "更新失败");}}/*** 更新，null值取数据库默认值** @param baseDTO* @param eClass* @param mapper* @param <E>* @return*/public static <E extends BaseInfo> Integer updateSelective(BaseDTO baseDTO, Class<E> eClass, Mapper<E> mapper) {log.info("更新AppDTO:{}", JSON.toJSONString(baseDTO));if (baseDTO == null) {throw new InstitutionException(400, "请求参数异常");}if (StringUtils.isBlank(baseDTO.getId())) {throw new InstitutionException(400, "id不能为空");}try {E e = JSON.parseObject(JSON.toJSONString(baseDTO), eClass);e.setGmtUpdate(new Date());e.setUserUpdate(baseDTO.getUserUpdate());return mapper.updateByPrimaryKeySelective(e);} catch (Exception e) {throw new InstitutionException(500, "更新失败");}}/*** 根据id删除** @param id* @param mapper* @param <E>* @return*/public static <E> Integer deleteById(String id, Mapper<E> mapper) {log.info("删除id：{}", id);return mapper.deleteByPrimaryKey(id);}}
2. json 转换类工具类：
package com.xxx.xxx.xxx.xxx.utils;import com.alibaba.fastjson.JSON;import java.util.ArrayList;import java.util.List;public class JsonTransUtils{/*** 转为新列表(对象属性名要相同)* @param originList 原列表* @param tClass 新列表类对象* @param <T>* @return*/public static <T> List<T> list2OtherList(List originList,Class<T> tClass){List<T> list = new ArrayList<>();for (Object info : originList) {T t = JSON.parseObject(JSON.toJSONString(info),tClass);list.add(t);}return list;}}
3. sql 工具类：
package com.xxx.xxx.xxx.xxx.utils;import lombok.extern.slf4j.Slf4j;import mons.lang3.StringUtils;import tk.mybatis.mapper.entity.Example;import java.lang.reflect.Field;@Slf4jpublic class SqlUtils {/*** 封装模糊查询条件,排序条件（不排序传“”或null）** @param t 封装查询条件类* @param orderByContent* @param <T>* @return* @throws IllegalAccessException*/public static <T> Example getSelectExample(T t, String orderByContent) throws IllegalAccessException {Example example = new Example(t.getClass());Example.Criteria criteria = example.createCriteria();if (!StringUtils.isBlank(orderByContent)) {example.setOrderByClause(orderByContent);}Field[] declaredFields = t.getClass().getDeclaredFields();for (Field field : declaredFields) {field.setAccessible(true);if (field.get(t) != null && !"serialVersionUID".equals(field.getName())) {criteria.andLike(field.getName(), "%" + field.get(t).toString() + "%");}}return example;}}
