Java 反射Excel对象集合 Java通过反射将 Excel 解析成对象集合实例
after95 人气:0想了解Java通过反射将 Excel 解析成对象集合实例的相关内容吗,after95在本文为您仔细讲解Java 反射Excel对象集合的相关知识和一些Code实例,欢迎阅读和指正,我们先划重点:Java,反射,Excel,对象集合,下面大家一起来学习吧。
1.这是一个通过Java反射机制解析的工具类
2.使用时只需创建对应的对象,并在Excel的第一行填上对应的属性名
3.首先要添加相关的jar包:
poi-3.8.jar
poi-ooxml-3.9.jar
poi-ooxml-schemas-3.9.jar
xmlbeans-2.6.0.jar
4.看一下Excel的内容:
5.创建对应的实体类:
package com.office.user.dto; public class UserDTO { private String idUser; private String userName; private String gender; private String birthDate; private String idType; private String idNo; private String mobile; public String getIdUser() { return idUser; } public void setIdUser(String idUser) { this.idUser = idUser; } public String getUserName() { return userName; } public void setUserName(String userName) { this.userName = userName; } public String getGender() { return gender; } public void setGender(String gender) { this.gender = gender; } public String getBirthDate() { return birthDate; } public void setBirthDate(String birthDate) { this.birthDate = birthDate; } public String getIdType() { return idType; } public void setIdType(String idType) { this.idType = idType; } public String getIdNo() { return idNo; } public void setIdNo(String idNo) { this.idNo = idNo; } public String getMobile() { return mobile; } public void setMobile(String mobile) { this.mobile = mobile; } @Override public String toString() { return "UserDTO [idUser=" + idUser + ", userName=" + userName + ", gender=" + gender + ", birthDate=" + birthDate + ", idType=" + idType + ", idNo=" + idNo + ", mobile=" + mobile + "]"; } }
6.编写工具类:ExcelReader.java
package com.office.poi; import java.io.File; import java.io.FileInputStream; import java.io.IOException; import java.lang.reflect.Field; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import org.apache.poi.ss.usermodel.Cell; import org.apache.poi.ss.usermodel.DataFormatter; import org.apache.poi.ss.usermodel.DateUtil; import org.apache.poi.ss.usermodel.Row; import org.apache.poi.ss.usermodel.Sheet; import org.apache.poi.ss.usermodel.Workbook; import org.apache.poi.ss.usermodel.WorkbookFactory; import com.office.user.dto.UserDTO; /** * Excel 解析工具 * * @author Neo 2017-5-15 * * 所需jar: poi-3.8.jar poi-ooxml-3.9.jar poi-ooxml-schemas-3.9.jar * xmlbeans-2.6.0.jar * */ public class ExcelReader { private String filePath; private String sheetName; private Workbook workBook; private Sheet sheet; private List<String> columnHeaderList; private List<List<String>> listData; private List<Map<String, String>> mapData; private boolean flag; public ExcelReader(String filePath, String sheetName) { this.filePath = filePath; this.sheetName = sheetName; this.flag = false; this.load(); } private void load() { FileInputStream inStream = null; try { inStream = new FileInputStream(new File(filePath)); workBook = WorkbookFactory.create(inStream); sheet = workBook.getSheet(sheetName); } catch (Exception e) { e.printStackTrace(); } finally { try { if (inStream != null) { inStream.close(); } } catch (IOException e) { e.printStackTrace(); } } } private String getCellValue(Cell cell) { String cellValue = ""; DataFormatter formatter = new DataFormatter(); if (cell != null) { switch (cell.getCellType()) { case Cell.CELL_TYPE_NUMERIC: if (DateUtil.isCellDateFormatted(cell)) { cellValue = formatter.formatCellValue(cell); } else { double value = cell.getNumericCellValue(); int intValue = (int) value; cellValue = value - intValue == 0 ? String.valueOf(intValue) : String.valueOf(value); } break; case Cell.CELL_TYPE_STRING: cellValue = cell.getStringCellValue(); break; case Cell.CELL_TYPE_BOOLEAN: cellValue = String.valueOf(cell.getBooleanCellValue()); break; case Cell.CELL_TYPE_FORMULA: cellValue = String.valueOf(cell.getCellFormula()); break; case Cell.CELL_TYPE_BLANK: cellValue = ""; break; case Cell.CELL_TYPE_ERROR: cellValue = ""; break; default: cellValue = cell.toString().trim(); break; } } return cellValue.trim(); } private void getSheetData() { listData = new ArrayList<List<String>>(); mapData = new ArrayList<Map<String, String>>(); columnHeaderList = new ArrayList<String>(); int numOfRows = sheet.getLastRowNum() + 1; for (int i = 0; i < numOfRows; i++) { Row row = sheet.getRow(i); Map<String, String> map = new HashMap<String, String>(); List<String> list = new ArrayList<String>(); if (row != null) { for (int j = 0; j < row.getLastCellNum(); j++) { Cell cell = row.getCell(j); if (i == 0) { columnHeaderList.add(getCellValue(cell)); } else { map.put(columnHeaderList.get(j), this.getCellValue(cell)); } list.add(this.getCellValue(cell)); } } if (i > 0) { mapData.add(map); } listData.add(list); } flag = true; } public String getCellData(int row, int col) { if (row <= 0 || col <= 0) { return null; } if (!flag) { this.getSheetData(); } if (listData.size() >= row && listData.get(row - 1).size() >= col) { return listData.get(row - 1).get(col - 1); } else { return null; } } public String getCellData(int row, String headerName) { if (row <= 0) { return null; } if (!flag) { this.getSheetData(); } if (mapData.size() >= row && mapData.get(row - 1).containsKey(headerName)) { return mapData.get(row - 1).get(headerName); } else { return null; } } /** * 获取标题 * * @param eh * @param maxX * @return */ public List<String> getTitleList(ExcelReader eh, int maxX) { List<String> result = new ArrayList<String>(); for (int i = 1; i <= maxX; i++) { result.add(eh.getCellData(1, i)); } return result; } /** * 获取单行对象 * * @param object * @param eh * @param maxX * @param titles * @return */ public Object getObject(String className, ExcelReader eh, int y, List<String> titles) throws Exception { Object bean = Class.forName(className).newInstance(); int length = titles.size(); for (int x = 0; x < length; x++) { try { Field field = bean.getClass().getDeclaredField(titles.get(x)); field.setAccessible(true); field.set(bean, eh.getCellData(y, x+1)); } catch (Exception e) { System.out.println("没有对应的方法:" + e); } } return bean; } /** * 获取Excel数据列表 * * @param bean * @param eh * @param x * 每行有多少列数据 * @param y * 整个sheet有多少行数据 * @param titles * @return */ public List<Object> getDataList(Class<?> clazz, ExcelReader eh, int x, int y, List<String> titles) { List<Object> result = new ArrayList<Object>(); String className = clazz.getName(); try { for (int i = 2; i <=y; i++) { Object object = eh.getObject(className, eh, i, titles); result.add(object); } } catch (Exception e) { System.out.println(e); } return result; } public static void main(String[] args) { try { ExcelReader eh = new ExcelReader("C:\\Users\\Neo\\Desktop\\POI.xlsx", "Sheet1"); List<String> titles = eh.getTitleList(eh, 7); List<Object> userList = eh.getDataList(UserDTO.class, eh, 7, 4, titles); for (Object object : userList) { System.out.println(object); } } catch (Exception e) { System.out.println(e); } } }
6.看一下测试结果:
备注:这是我写于两年前的测试demo,如果生产上有类似需求更建议使用 EasyExcel
补充知识:简单好用-JAVA使用POI解析Excel
相信使用POI的目前已经非常多了,我这边提供一个非常简单便利又通用的POI解析工具类,代码最后有示例代码。可以按照本文直接使用。
import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.IOException; import java.io.InputStream; import java.text.DecimalFormat; import java.text.SimpleDateFormat; import java.util.ArrayList; import java.util.Date; import java.util.HashMap; import java.util.List; import java.util.Map; import org.apache.log4j.LogManager; import org.apache.log4j.Logger; import org.apache.poi.hssf.usermodel.HSSFCell; import org.apache.poi.hssf.usermodel.HSSFDateUtil; import org.apache.poi.hssf.usermodel.HSSFRow; import org.apache.poi.hssf.usermodel.HSSFSheet; import org.apache.poi.hssf.usermodel.HSSFWorkbook; import org.apache.poi.poifs.filesystem.POIFSFileSystem; /** * * Title: ExcelReader<br> * Description: 可以读取xls,xlsx等文件<br> * Copyright @ 2012~2016 xiaour.github.com<span style="font-size: 1em;"> .All rights reserved.<br></span> * @author 小鱼儿 * @createDate 2016年8月23日 * @version v1.0 */ public class ExcelReader { private POIFSFileSystem fs; private HSSFWorkbook wb; private HSSFSheet sheet; private HSSFRow row; private static Logger logger = LogManager.getLogger(ExcelReader.class); private String fileFullPath; private int sheetNo; public ExcelReader(String fileFullPath, int sheetNo) { super(); this.fileFullPath = fileFullPath; this.sheetNo = sheetNo; } /** * 读取Excel数据内容 * @param InputStream * @param sheetNo sheet 页号 * @return Map 包含单元格数据内容的Map对象 */ public List<Map<String,Object>> readExcel() { logger.info("开始解析xls..."); sheetNo--;//从1开始及从0开始 InputStream is = null; try { is = new FileInputStream(fileFullPath); } catch (FileNotFoundException e1) { logger.error(e1); } Map<String,Object> dataMap = null; List<Map<String,Object>> dataList= new ArrayList<>(); String value = ""; try { fs = new POIFSFileSystem(is); wb = new HSSFWorkbook(fs); } catch (IOException e) { logger.error(e); } sheet = wb.getSheetAt(sheetNo); row = sheet.getRow(0); // 标题总列数 int colNum = row.getPhysicalNumberOfCells(); String[] keyArray = new String[colNum]; for (int i = 0; i < colNum; i++) { keyArray[i] = getCellFormatValue(row.getCell((short) i)); } int rowNum = sheet.getLastRowNum(); // 正文内容应该从第二行开始,第一行为表头的标题 for (int i = 2; i <= rowNum; i++) { dataMap= new HashMap<>(); row = sheet.getRow(i); if(row!=null){ int j = 0; while (j < colNum) { //这里把列循环到Map if(row.getCell((short) j)!=null){ value = getCellFormatValue(row.getCell((short) j)).trim(); dataMap.put(keyArray[j],value); } j++; } value = ""; dataList.add(dataMap); } } logger.info("解析xls完成..."); try { if(is!=null) is.close(); } catch (IOException e) { logger.error(e.toString()); } return dataList; } /** * 根据HSSFCell类型设置数据 * @param cell * @return */ private String getCellFormatValue(HSSFCell cell) { String cellvalue = ""; if (cell != null) { // 判断当前Cell的Type switch (cell.getCellType()) { // 如果当前Cell的Type为NUMERIC case HSSFCell.CELL_TYPE_NUMERIC: case HSSFCell.CELL_TYPE_FORMULA: { // 判断当前的cell是否为Date if (HSSFDateUtil.isCellDateFormatted(cell)) { Date date = cell.getDateCellValue(); SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd"); cellvalue = sdf.format(date); } // 如果是纯数字 else { // 取得当前Cell的数值 DecimalFormat df = new DecimalFormat("0"); String dfStr = df.format(cell.getNumericCellValue()); cellvalue = dfStr; } break; } // 如果当前Cell的Type为STRIN case HSSFCell.CELL_TYPE_STRING: // 取得当前的Cell字符串 cellvalue = cell.getRichStringCellValue().getString(); break; // 默认的Cell值 default: cellvalue = " "; } } else { cellvalue = ""; } return cellvalue; } public static void main(String[] args) { List<Map<String, Object>> dataList; // 对读取Excel表格标题测试 ExcelReader excelReader = new ExcelReader("D:\\okcoin-2016-08-3XZS.xls",1); dataList = excelReader.readExcel(); for(Map<String,Object> theMap:dataList){ System.out.println(theMap); } } }
这个类导入相应的jar之后就可以用了哦。
以上这篇Java通过反射将 Excel 解析成对象集合实例就是小编分享给大家的全部内容了,希望能给大家一个参考,也希望大家多多支持。
加载全部内容