Spring Boot中前端通过请求接口下载后端存放的Excel模板

导出工具类

package com.yutu.garden.utils;

import com.baomidou.mybatisplus.core.toolkit.ObjectUtils;
import org.apache.commons.io.IOUtils;
import org.apache.poi.hssf.util.HSSFColor;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.apache.poi.hssf.usermodel.*;
import org.apache.poi.ss.usermodel.*;
import org.springframework.core.io.ResourceLoader;
import org.springframework.stereotype.Component;
import org.springframework.web.multipart.MultipartFile;

import javax.annotation.Resource;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.*;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;
import java.text.DecimalFormat;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;


/**
 * @ClassName: ExcelUtils
 * @Description: Excel相关操作
 * @Author
 * @Date 2022/4/11
 * @Version 1.0
 */
@Component
public class ExcelUtils {

	@Resource
	private  ResourceLoader resourceLoader;
	private static Logger log = LoggerFactory.getLogger(ExcelUtils.class);
	static{
		System.setProperty("java.awt.headless", "true");
	}

	/**
	 * 设置表头
	 * @param sheet sheet
	 * @param str 表头数据
	 * @param startNum 开始行
	 * @param height 高度
	 * @param style 样式
	 */
	public static void setTitle(HSSFSheet sheet, String[] str,int startNum,Short height,HSSFCellStyle style,Integer[] widths,int width) {
		try {
			HSSFRow row = sheet.createRow(startNum);
			if(ObjectUtils.isEmpty(height)){
				height = (short)(20*20);
			}
			row.setHeight(height);
			//创建表头名称
			HSSFCell cell;
			for (int j = 0; j < str.length; j++) {
				cell = row.createCell(j);

				//设置列宽，setColumnWidth的第二个参数要乘以256，这个参数的单位是1/256个字符宽度
				if(ObjectUtils.isNotEmpty(widths) && ObjectUtils.isNotEmpty(widths[j]) ){
					sheet.setColumnWidth(j, widths[j]);
				}else{
					sheet.autoSizeColumn(j);
					int colWidth = sheet.getColumnWidth(j) * width / 10;
//					if (colWidth > 255) {
//						colWidth = 255;
//					}

					sheet.setColumnWidth(j, colWidth);
				}

				cell.setCellValue(str[j]);
				cell.setCellStyle(style);
			}
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	public static void setTitle(HSSFSheet sheet, List<String> str,int startNum,Short height,HSSFCellStyle style,Integer[] widths) {
		try {
			HSSFRow row = sheet.createRow(startNum);
			if(ObjectUtils.isEmpty(height)){
				height = (short)(20*20);
			}
			row.setHeight(height);
			//创建表头名称
			HSSFCell cell;
			for (int j = 0; j < str.size(); j++) {
				cell = row.createCell(j);

				//设置列宽，setColumnWidth的第二个参数要乘以256，这个参数的单位是1/256个字符宽度
				if(ObjectUtils.isNotEmpty(widths) && ObjectUtils.isNotEmpty(widths[j]) ){
					sheet.setColumnWidth(j, widths[j]);
				}else{
					sheet.autoSizeColumn(j);
					sheet.setColumnWidth(j, sheet.getColumnWidth(j) * 30 / 10);
				}

				cell.setCellValue(str.get(j));
				cell.setCellStyle(style);
			}
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	/**
	 * 方法名：setData
	 * 功能：表格赋值
	 */
	public static void setData(HSSFSheet sheet, List<Object[]> data,int startNum,HSSFCellStyle style) {
		try{
			int rowNum = startNum+1;
			for (int i = 0; i < data.size(); i++) {
				HSSFRow row = sheet.createRow(rowNum);
				for (int j = 0; j < data.get(i).length; j++) {
					HSSFCell cell = row.createCell(j);
					if(ObjectUtils.isEmpty(data.get(i)[j])){
						cell.setCellValue("");
					}else{
						cell.setCellValue(data.get(i)[j].toString());
					}
					cell.setCellStyle(style);
				}
				rowNum++;
			}
		}catch (Exception e){
			e.printStackTrace();
		}
	}

	public static void setDataByList(HSSFSheet sheet, List<List<Object>> data,int startNum) {
		try{
			int rowNum = startNum+1;
			for (int i = 0; i < data.size(); i++) {
				HSSFRow row = sheet.createRow(rowNum);

				for (int j = 0; j < data.get(i).size(); j++) {
					if(ObjectUtils.isEmpty(data.get(i).get(j))){
						row.createCell(j).setCellValue("");
					}else{
						row.createCell(j).setCellValue(data.get(i).get(j).toString());
					}
				}
				rowNum++;
			}
		}catch (Exception e){
			e.printStackTrace();
		}
	}

	/**
	 * 方法名：setBrowser
	 * 功能：使用浏览器下载
	 */
	public static void setBrowser(HttpServletResponse response, HSSFWorkbook workbook, String fileName) {
		try {
			//清空response
			//response.reset();
			//设置response的Header
			String name = URLEncoder.encode(fileName, "UTF-8");
			//Content-disposition 的 attachment参数将文件作为附件下载
			//response.setHeader("Content-disposition", "attachment;filename=" + fileName+".xlsx");
			response.setHeader( "Content-Disposition", "attachment;filename=\"" + name + "\".xlsx;filename*=utf-8''" + name +".xlsx");

			OutputStream os = new BufferedOutputStream(response.getOutputStream());
			response.setContentType("application/vnd.ms-excel");
			response.setCharacterEncoding("utf-8");
			//将excel写入到输出流中
			workbook.write(os);
			os.flush();
			os.close();
		} catch (Exception e) {
			e.printStackTrace();
		}

	}

	/**
	 * 居中
	 * @param workbook
	 * @return
	 */
	public static HSSFCellStyle getStyleByCENTER(HSSFWorkbook workbook,int size){
		//设置标题样式
		HSSFCellStyle style = workbook.createCellStyle();
		HSSFFont font = workbook.createFont();
		font.setBold(true);
		font.setFontName("宋体");
		font.setFontHeightInPoints((short) size);
		style.setFont(font);
		//水平居中
		style.setAlignment(HorizontalAlignment.CENTER);
		//垂直居中
		style.setVerticalAlignment(VerticalAlignment.CENTER);
		style.setDataFormat(HSSFDataFormat.getBuiltinFormat("m/d/yy h:mm"));
		return style;
	}

	/**
	 * 带边框的样式
	 * @param workbook workbook
	 * @param size 字体大小
	 * @param isText 是否正文
	 * @return
	 */
	public static HSSFCellStyle getStyleByBorder(HSSFWorkbook workbook,int size,boolean isText){
		//设置标题样式
		HSSFCellStyle style = workbook.createCellStyle();
		HSSFFont font = workbook.createFont();
		if(!isText){
			font.setBold(true);
		}
		font.setFontName("宋体");
		font.setFontHeightInPoints((short) size);
		style.setFont(font);
		//水平居中
		style.setAlignment(HorizontalAlignment.CENTER);
		//垂直居中
		style.setVerticalAlignment(VerticalAlignment.CENTER);
		style.setDataFormat(HSSFDataFormat.getBuiltinFormat("m/d/yy h:mm"));
		//边框
		style.setBorderBottom(BorderStyle.THIN);
		style.setBorderLeft(BorderStyle.THIN);
		style.setBorderTop(BorderStyle.THIN);
		style.setBorderRight(BorderStyle.THIN);
		return style;
	}


	public static HSSFCellStyle getDataStyle(HSSFWorkbook workbook,int size,boolean isSetBold,HSSFColor.HSSFColorPredefined background){
		//设置标题样式
		HSSFCellStyle style = workbook.createCellStyle();
		HSSFFont font = workbook.createFont();
		font.setBold(isSetBold);
		font.setFontName("宋体");
		font.setFontHeightInPoints((short) size);
		style.setFont(font);
		if(ObjectUtils.isNotEmpty(background)){//设置填充方式
			style.setFillPattern(FillPatternType.SOLID_FOREGROUND);
			style.setFillForegroundColor(background.getIndex());
		}
		return style;
	}

	/**
	 * 解析上传的excel， 默认只解析第一张Sheet
	 *
	 * @param file     excel
	 * @param startRow 数据开始行
	 * @return List<String [ ]>
	 * @throws IOException
	 */
	public static List<String> getExcelData(MultipartFile file, int startRow, Integer endRow){
		int resultSize = 0;
		ArrayList<String> resultData = new ArrayList<>(resultSize);
		try {
			if (!checkFile(file)) {
				log.error("上传的excel文件格式有问题");
				return resultData;
			}

			//获得Workbook工作薄对象
			Workbook workbook = getWorkBook(file);
			if (ObjectUtils.isNotEmpty(workbook)) {
				//获取第一张sheet工作表
				Sheet sheet = workbook.getSheetAt(0);
				if (ObjectUtils.isEmpty(sheet)) {
					return resultData;
				}

				// 重新初始化List结果大小
				resultSize = sheet.getLastRowNum() + 1;
				//获得当前sheet的开始行
				int firstRowNum = sheet.getFirstRowNum();
				//获得当前sheet的结束行
				int lastRowNum = sheet.getLastRowNum();
				if(ObjectUtils.isNotEmpty(endRow)){
					lastRowNum = endRow;
				}

				//循环除了startRow的所有行,如果要循环除第一行以外的就firstRowNum+1
				for (int rowNum = firstRowNum + startRow; rowNum <= lastRowNum; rowNum++) {
					//获得当前行
					Row row = sheet.getRow(rowNum);
					if (rowIsEmpty(row)) {
						break;
					}
					//获得当前行的开始列
					int firstCellNum = row.getFirstCellNum();
					//获得当前行的列数
					int lastCellNum = row.getLastCellNum();
					//String[] cells = new String[lastCellNum];
					StringBuilder stringBuffer = new StringBuilder();
					//循环当前行
					for (int cellNum = firstCellNum; cellNum < lastCellNum; cellNum++) {
						Cell cell = row.getCell(cellNum);
						//cells[cellNum] = getCellValue(cell);
						String cellValue = getCellValue(cell);
						stringBuffer.append(getCellValue(cell)).append(",&");//加个&防止有答案中有,的
					}
					//resultData.add(cells);
					resultData.add(stringBuffer.toString());
				}
				workbook.close();
			}
		} catch (IOException e) {
			e.printStackTrace();
		}

		return resultData;
	}


	/**
	 * 检查文件格式
	 *
	 * @param file
	 * @throws IOException
	 */
	public static boolean checkFile(MultipartFile file) throws IOException {
		if (null == file) {
			log.error("文件不存在！");
			return false;
		}
		//获得文件名
		String fileName = file.getOriginalFilename();
		//判断文件是否是excel文件
		if (ObjectUtils.isEmpty(fileName) || (!fileName.endsWith("xls") && !fileName.endsWith("xlsx"))) {
			log.error(fileName + "不是excel文件");
			return false;
		}
		return true;
	}

	/**
	 * 获取工作簿对象
	 *
	 * @param file
	 * @return
	 */
	public static Workbook getWorkBook(MultipartFile file) {
		//获得文件名
		String fileName = file.getOriginalFilename();
		//创建Workbook工作薄对象，表示整个excel
		Workbook workbook = null;
		try {
			//获取excel文件的io流
			InputStream is = file.getInputStream();
			//根据文件后缀名不同(xls和xlsx)获得不同的Workbook实现类对象
			if(ObjectUtils.isNotEmpty(fileName)){
				if (fileName.endsWith("xls")) {
					//2003
					workbook = new HSSFWorkbook(is);
				} else if (fileName.endsWith("xlsx")) {
					//2007 及2007以上
					workbook = new XSSFWorkbook(is);
				}
			}
		} catch (IOException e) {
			log.error(e.getMessage());
		}
		return workbook;
	}

	public static String getCellValue(Cell cell) {
		String cellValue = "";
		if (cell == null) {
			return cellValue;
		}
		switch (cell.getCellTypeEnum()) {
			case NUMERIC:
				//数字
				cellValue = stringDateProcess(cell);
				break;
			case STRING:
				//字符串
				cellValue = String.valueOf(cell.getStringCellValue());
				break;
			case BOOLEAN:
				//Boolean
				cellValue = String.valueOf(cell.getBooleanCellValue());
				break;
			case FORMULA:
				//公式
				cellValue = String.valueOf(cell.getCellFormula());
				break;
			case BLANK:
				//空值
				cellValue = "";
				break;
			case ERROR:
				//故障
				cellValue = "非法字符";
				break;
			default:
				cellValue = "未知类型";
				break;
		}
		return cellValue;
	}


	public static String stringDateProcess(Cell cell) {
		String result = new String();
		if (HSSFDateUtil.isCellDateFormatted(cell)) {
			// 处理日期格式、时间格式
			SimpleDateFormat sdf = null;
			if (cell.getCellStyle().getDataFormat() == HSSFDataFormat.getBuiltinFormat("h:mm")) {
				sdf = new SimpleDateFormat("HH:mm");
			} else {// 日期
				sdf = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
			}
			Date date = cell.getDateCellValue();
			result = sdf.format(date);
		} else if (cell.getCellStyle().getDataFormat() == 58) {
			// 处理自定义日期格式：m月d日(通过判断单元格的格式id解决，id的值是58)
			SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
			double value = cell.getNumericCellValue();
			Date date = org.apache.poi.ss.usermodel.DateUtil
				.getJavaDate(value);
			result = sdf.format(date);
		} else {
			double value = cell.getNumericCellValue();
			CellStyle style = cell.getCellStyle();
			DecimalFormat format = new DecimalFormat();
			String temp = style.getDataFormatString();
			// 单元格设置成常规
			if ("General".equals(temp)) {
				int decimalPlaces = countDecimalPlaces(value);
				StringBuilder pattern = new StringBuilder("#.");
				for (int i = 0; i < decimalPlaces; i++) {
					pattern.append("#");
				}
				format.applyPattern(pattern.toString());
			}
			result = format.format(value);
		}

		return result;
	}

	public static int countDecimalPlaces(double value) {
		String stringValue = Double.toString(value);
		int integerPlaces = stringValue.indexOf('.');
		return stringValue.length() - integerPlaces - 1;
	}

	/**
	 * @return * @param null
	 * @Author
	 * @Description //TODO 判断excel的row是否全为空
	 * @Date 2019/12/2 19:30
	 * @Param
	 */
	public static boolean rowIsEmpty(Row row) {
		if (null == row) {
			return true;
		}
		for (int c = row.getFirstCellNum(); c < row.getLastCellNum(); c++) {
			Cell cell = row.getCell(c);
			if (cell != null && cell.getCellTypeEnum() != CellType.BLANK) {
				return false;
			}
		}
		return true;
	}

	/**
	 * 模板下载
	 * @param response
	 * @param request
	 * @param filename
	 * @param path
	 * @throws IOException
	 */
	public void downloadTemplate(HttpServletResponse response, HttpServletRequest request, String filename, String path) throws IOException {

		InputStream inputStream = null;
		ServletOutputStream servletOutputStream = null;
		try {
			org.springframework.core.io.Resource resource = resourceLoader.getResource("classpath:" + path);

			response.setContentType("application/vnd.ms-excel");
			response.addHeader("Cache-Control", "no-cache, no-store, must-revalidate");
			response.addHeader("charset", "utf-8");
			response.addHeader("Pragma", "no-cache");
			String encodeName = URLEncoder.encode(filename, StandardCharsets.UTF_8.toString());
			response.setHeader("Content-Disposition", "attachment; filename=\"" + encodeName + "\"; filename*=utf-8''" + encodeName);

			inputStream = resource.getInputStream();
			servletOutputStream = response.getOutputStream();
			IOUtils.copy(inputStream, servletOutputStream);
			response.flushBuffer();
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			try {
				if (servletOutputStream != null) {
					servletOutputStream.close();
				}
				if (inputStream != null) {
					inputStream.close();
				}
				// jvm的垃圾回收
				System.gc();
			} catch (Exception e) {
				e.printStackTrace();
			}
		}
	}
}

控制层接口

package com.yutu.garden.controller;

import com.yutu.garden.utils.ExcelUtilsWP;
import io.swagger.annotations.Api;
import io.swagger.annotations.ApiOperation;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import javax.annotation.Resource;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

@RestController
@RequestMapping("excel")
@Api(tags = "Excel模板下载")
public class ExcelTemplateController {

	@Resource
	private ExcelUtilsWP excelUtils;

	@ApiOperation("下载苗木计划清单模板")
	@GetMapping("/downloadPunishTemplate")
	public void downloadPunishTemplate(HttpServletResponse response, HttpServletRequest request) throws IOException {
		String filename = "苗木计划清单模板.xlsx";
		String path = "template/苗木计划清单模板.xlsx";
		excelUtils.downloadTemplate(response,request,filename,path);
	}
}