设计模式之策略模式

背景：导入功能需要做成根据编码code或者名称实现不同的导入逻辑，编码和名称都是可配置的，未知的变化，这里要写通用的导入、校验和具体的导入、校验。至此我想到采用设计模式之策略模式+工厂模式实现此需求。若有不妥还望指正。

1. 自定义注解
2. 创建工厂
3. spring启动扫描带注解的策略类放入工厂中
4. 定义接口+方法
5. 定义策略类
6. api调用根据code获取对应策略的实现类

至此大致的思路确定下面就是具体的代码实现细节

自定义注解

此处定义了三个属性，目前只用到了一个

import org.springframework.stereotype.Component;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;/*** 自定义注解*/
@Retention(RetentionPolicy.RUNTIME) // 作用于运行时
@Target(ElementType.TYPE)   // 作用于类上
@Component
public @interface ImportService {String templateCode();int sheetIndex() default 0;String sheetName() default "";
}

创建工厂

定义importRegisterRespository 存储策略实体类信息

import org.springframework.stereotype.Component;
import java.util.HashMap;
import java.util.Map;@Component
public class ImportRegisterRespository {private Map<String, Object> importRegisterRespository = new HashMap<>();public Map<String, Object> getImportRegisterRespository(){return importRegisterRespository;}
}

扫描策略类放入map中

扫描带ImportService 注解的类进行扫描，并放入map中

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.ApplicationContext;
import org.springframework.core.annotation.AnnotationUtils;
import org.springframework.stereotype.Component;
import org.springframework.util.ClassUtils;
import javax.annotation.PostConstruct;
import java.util.Map;@Component
public class ImportInitiator {@Autowiredprivate ImportRegisterRespository importRegisterRespository;@Autowiredprivate ApplicationContext applicationContext;@PostConstructpublic void init(){Map<String, Object> extensionBeans = applicationContext.getBeansWithAnnotation(ImportService.class);for(Object bean : extensionBeans.values()){Class<?> extensionClz = ClassUtils.getUserClass(bean);ImportService extension = AnnotationUtils.findAnnotation(extensionClz, ImportService.class);String templateCode = extension.templateCode();importRegisterRespository.getImportRegisterRespository().put(templateCode, bean);}}
}

定义接口

定义2个方法，导入和验证

import com.alibaba.fastjson2.JSONObject;
import com.example.demo.dto.importVO.ImportLine;
import java.util.List;public interface IBatchImportItf{List<String> doBatchImport(List<JSONObject> data);Boolean validate(List<ImportLine> importLineList);
}

定义策略类

此类是个半成品，具体的实现还没写完，不过大致思路都成型
可以继续写其他策略类，以此类推

import com.alibaba.fastjson2.JSONObject;
import com.example.demo.dto.importVO.ImportLine;
import com.example.demo.importHandler.init.ImportService;
import org.springframework.stereotype.Component;
import java.util.*;@Component
@ImportService(templateCode = "BASE_IMPORT")
public class BaseImport implements IBatchImportItf {@Overridepublic List<String> doBatchImport(List<JSONObject> data) {List<String> lists = new ArrayList<>();for (JSONObject datum : data) {//插入表中 返回当前的批次号给前端String uuid = UUID.randomUUID().toString();lists.add(uuid);}//前端拿着批号导入正式表中return lists;}@Overridepublic Boolean validate(List<ImportLine> importLineList) {for (ImportLine importLine : importLineList) {//根据uuid去数据库查数据 返回一个listimportLine = new ImportLine(1L,"xxxxx",1,"","具体的json数据");JSONObject jsonObject = new JSONObject();//模拟数据jsonObject.put("order",1);jsonObject.put("age",20);jsonObject.put("gender","M-男");jsonObject.put("province","河南");jsonObject.put("city","郑州");jsonObject.put("country","中原区");//模拟规则  判空规则  根据 sheetCode查出配置的信息Map<String,String> nullableFlagMap = new HashMap<String,String>(){{put("age","Y");put("province","Y");put("city","Y");put("country","Y");}};for (String key : nullableFlagMap.keySet()) {if(Objects.isNull(jsonObject.get(key))){importLine.setMsg(key+"不允许为空");}}//更新 ImportLine 根据 batchId 和 rowIndex 去更新数据库}return null;}
}

api调用

此api也是个半成品，不过思路已确定
api分三部分：
1、导入临时表，临时表返回批次id
2、通用验证，根据配置验证，主要是验证必输性，根据第一步的批次id查询数据验证，返回boolean值，当返回true再根据具体的策略实现类业务验证
3、导入正式表

import com.alibaba.fastjson2.JSONObject;
import com.example.demo.dto.importVO.ImportLine;
import com.example.demo.dto.importVO.TemplateDO;
import com.example.demo.dto.importVO.TemplateSheet;
import com.example.demo.dto.importVO.TemplateSheetCol;
import com.example.demo.importHandler.IBatchImportItf;
import com.example.demo.importHandler.init.ImportRegisterRespository;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang3.StringUtils;
import org.apache.poi.ss.usermodel.*;
import org.apache.poi.ss.util.CellRangeAddress;
import org.apache.poi.ss.util.CellRangeAddressList;
import org.apache.poi.xssf.usermodel.*;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpHeaders;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.util.Assert;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.*;	@AutowiredImportRegisterRespository importRegisterRespository;@PostMapping("/import/temp")public List<String> importTemp(MultipartFile file) {Optional.ofNullable(file).orElseThrow(() -> new RuntimeException("文件不能为空"));//获取初始化的导入对象Map<String, Object> importServiceMap = importRegisterRespository.getImportRegisterRespository();//先执行basr类 BASE_IMPORTIBatchImportItf baseImport = (IBatchImportItf)importServiceMap.get("BASE_IMPORT");/*1 读取excel数据2 先查出模板配置信息，转换成kv对象，k是排序跟excel的col匹配，v是字段驼峰编码跟excel的值匹配比如：kv - {"1":"city"} excel从左往右读取数据，读到1从kv中获取city再拿excel中的具体值，组装数据{"city":"郑州市"}3 这个就是最终要的结果 {"city":"郑州市","provice":"河南省","gender":"男"}*/InputStream inputStream = null;Workbook workbook = null;try{inputStream = file.getInputStream();workbook = new XSSFWorkbook(inputStream);// 获取工作簿中的所有工作表数量int numberOfSheets = workbook.getNumberOfSheets();List<String> sheetUUID = new ArrayList<>();// 遍历每一个工作表for (int i = 0; i < numberOfSheets; i++) {Sheet sheet = workbook.getSheetAt(i);System.out.println("Sheet name: " + sheet.getSheetName());if (workbook.isSheetHidden(i)) {System.out.println("Sheet is hidden netx one.");continue;}// 检查工作表是否被隐藏// 遍历行// 遍历每一行，从第3行开始（索引为1），第一行是说明，第二行是标题List<JSONObject> list = new ArrayList<>();for (int rowIndex = 2; rowIndex <= sheet.getLastRowNum(); rowIndex++) {Row row = sheet.getRow(rowIndex);if (row == null) {// 如果行为空，则跳过continue;}//模拟查询到数据sheet页列的数据信息HashMap<Integer, String> sheetColMap = new HashMap<Integer, String>() {{put(0, "order");put(1, "age");put(2, "gender");put(3, "province");put(4, "city");put(5, "country");}};JSONObject jsonObject = new JSONObject();// 遍历单元格for (int j = 0; j < Integer.parseInt(String.valueOf(row.getLastCellNum())); j++) {Cell cell = row.getCell(j);String keyName = sheetColMap.get(j);switch (cell.getCellType()) {case STRING:System.out.print(cell.getStringCellValue() + "\t");jsonObject.put(keyName,cell.getStringCellValue());break;case NUMERIC:if (DateUtil.isCellDateFormatted(cell)) {System.out.print(cell.getDateCellValue() + "\t");jsonObject.put(keyName,cell.getDateCellValue());} else {System.out.print(cell.getNumericCellValue() + "\t");jsonObject.put(keyName,cell.getNumericCellValue());}break;case BOOLEAN:System.out.print(cell.getBooleanCellValue() + "\t");jsonObject.put(keyName,cell.getBooleanCellValue());break;case FORMULA:System.out.print(cell.getCellFormula() + "\t");jsonObject.put(keyName,cell.getCellFormula());break;default:System.out.print("UNKNOWN\t");jsonObject.put(keyName,"UNKNOWN");break;}System.out.println(jsonObject);}//至此一行读取完毕list.add(jsonObject);}sheetUUID.addAll(baseImport.doBatchImport(list));}return sheetUUID;} catch (IOException e) {throw new RuntimeException(e);}finally {try {inputStream.close();} catch (IOException e) {throw new RuntimeException(e);}try {workbook.close();} catch (IOException e) {throw new RuntimeException(e);}}}@PostMapping("/import/validate")public void importValidate(@RequestBody List<String> uuidList) {//获取初始化的导入对象Map<String, Object> importServiceMap = importRegisterRespository.getImportRegisterRespository();//先执行base类 BASE_IMPORTIBatchImportItf baseImport = (IBatchImportItf)importServiceMap.get("BASE_IMPORT");//根据uuid查到sheetCode，根据sheetCode在map中找到对应的实现类Boolean baseValidate = baseImport.validate(Arrays.asList(new ImportLine()));//todo 更新ImportLine表的错误信息，只要更新msg字段就代表错误//基础校验通过 继续走业务校验if(baseValidate){for (String uuid : uuidList) {//根据uuid查到sheetCode，根据sheetCode在map中找到对应的实现类String sheetItemCode = "one";IBatchImportItf itemImport = (IBatchImportItf)importServiceMap.get(sheetItemCode);itemImport.validate(Arrays.asList(new ImportLine()));//todo 更新ImportLine表的错误信息，只要更新msg字段就代表错误}}}@PostMapping("/import/business-table")public void importBusinessTable(@RequestBody List<String> uuidList) {for (String uuid : uuidList) {String sheetCode = "one";//根据uuid查到sheetCode 再拿出jsonDate//获取初始化的导入对象Map<String, Object> importServiceMap = importRegisterRespository.getImportRegisterRespository();//先执行base类 BASE_IMPORTIBatchImportItf itemImport = (IBatchImportItf)importServiceMap.get(sheetCode);itemImport.doBatchImport(null);}}