excel导出实例 - 技术栈

技术方案	最大记录数	内存占用特点
SSF（2003）	65,536	全内存操作，易溢出
XSSF（2007）	1,048,576	全内存操作，大文件仍会溢出
SXSSF（POI3.8+）	无硬性限制	通过临时文件缓存数据

基础XSSF导出（适合小数据量）

java 复制代码

public class BasicExcelExport {
    public static void export(HttpServletResponse response, 
                            Map<String, Object[]> data, 
                            String fileName) throws IOException {
        XSSFWorkbook workbook = new XSSFWorkbook();
        XSSFSheet sheet = workbook.createSheet("Sheet1");
        
        // 填充数据
        Set<String> keys = data.keySet();
        int rowNum = 0;
        for (String key : keys) {
            Row row = sheet.createRow(rowNum++);
            Object[] objArr = data.get(key);
            for (int i = 0; i < objArr.length; i++) {
                Cell cell = row.createCell(i);
                cell.setCellValue(objArr[i].toString());
            }
        }

        // 设置响应头
        response.setContentType("application/vnd.ms-excel");
        response.setHeader("Content-disposition", "attachment;filename=" + fileName);
        
        // 输出流
        workbook.write(response.getOutputStream());
        workbook.close();
    }
}

SXSSF流式导出（适合大数据量）

java 复制代码

public class BigDataExcelExport {
    public static void exportLargeData(HttpServletResponse response, 
                                     List<Map<String, Object>> dataList,
                                     String fileName) throws IOException {
        // 设置内存中保留1000行，超出部分写入临时文件
        SXSSFWorkbook workbook = new SXSSFWorkbook(1000); 
        Sheet sheet = workbook.createSheet("Data");
        
        // 表头
        Row headerRow = sheet.createRow(0);
        Set<String> keys = dataList.get(0).keySet();
        int colNum = 0;
        for (String key : keys) {
            headerRow.createCell(colNum++).setCellValue(key);
        }

        // 数据行
        int rowNum = 1;
        for (Map<String, Object> data : dataList) {
            Row row = sheet.createRow(rowNum++);
            colNum = 0;
            for (String key : keys) {
                row.createCell(colNum++).setCellValue(data.get(key).toString());
            }
        }

        // 输出
        response.setContentType("application/vnd.ms-excel");
        response.setHeader("Content-disposition", "attachment;filename=" + fileName);
        workbook.write(response.getOutputStream());
        workbook.dispose(); // 清理临时文件
    }
}

CSV格式导出（最高性能方案）

java 复制代码

public class CsvExport {
    public static void exportToCsv(HttpServletResponse response,
                                  List<String[]> dataLines,
                                  String fileName) throws IOException {
        // 设置响应头
        response.setContentType("text/csv");
        response.setHeader("Content-disposition", "attachment;filename=" + fileName);
        
        // 使用try-with-resources自动关闭流
        try (PrintWriter writer = response.getWriter()) {
            // 写入CSV内容
            for (String[] line : dataLines) {
                writer.println(String.join(",", line));
            }
        }
    }
}

代码封装

业务调用

java 复制代码

@GetMapping("/exportMemberExcle")
public void exportMemberExcle(HttpServletResponse response) {
    String fileName = "会员数据.xlsx";
    String sheetName = "会员列表";
    
    // 列宽配置（单位：字符数）
    int[] columnWidths = {20, 30, 20}; 
    
    // 构建数据（TreeMap自动排序）
    Map<String, Object[]> data = new TreeMap<>();
    data.put("1", new Object[]{"会员ID", "手机号", "注册时间"}); // 表头
    
    // 模拟数据填充（实际应从数据库获取）
    List<Member> members = memberService.getAllMembers();
    int rowNum = 2;
    for (Member member : members) {
        data.put(String.valueOf(rowNum++), 
            new Object[]{
                member.getId(),
                member.getPhone(),
                member.getRegisterTime()
            });
    }

    try {
        ExportExcel.generateExcel(response, data, fileName, sheetName, columnWidths);
    } catch (IOException e) {
        log.error("导出失败", e);
    }
}

工具类

java 复制代码

import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import javax.servlet.http.HttpServletResponse;
import java.io.OutputStream;
import java.util.Map;
import java.util.Set;

public class ExportExcel {
    public static void generateExcel(HttpServletResponse response, 
                                   Map<String, Object[]> data, 
                                   String fileName, 
                                   String sheetName,
                                   int[] columnWidths) throws IOException {
        // 创建工作簿和工作表
        XSSFWorkbook workbook = new XSSFWorkbook();
        XSSFSheet sheet = workbook.createSheet(sheetName);

        // 设置列宽（单位：字符数*256）
        for (int i = 0; i < columnWidths.length; ++i) {
            sheet.setColumnWidth(i, columnWidths[i] * 256);
        }

        // 填充数据
        Set<String> keyset = data.keySet();
        int rownum = 0;
        for (String key : keyset) {
            Row row = sheet.createRow(rownum++);
            Object[] objArr = data.get(key);
            int cellnum = 0;
            for (Object obj : objArr) {
                Cell cell = row.createCell(cellnum++);
                setCellValue(obj, cell); // 类型安全设置单元格值
            }
        }

        // 设置响应头（解决中文文件名乱码）
        fileName = new String(fileName.getBytes("GBK"), "ISO-8859-1");
        response.setContentType("application/vnd.ms-excel");
        response.setHeader("Content-disposition", "attachment;filename=" + fileName);

        // 流式输出
        OutputStream ouputStream = response.getOutputStream();
        workbook.write(ouputStream);
        ouputStream.flush();
        ouputStream.close();
    }

    private static void setCellValue(Object obj, Cell cell) {
        if (obj instanceof String) {
            cell.setCellValue((String) obj);
        } else if (obj instanceof Integer) {
            cell.setCellValue((Integer) obj);
        } else if (obj instanceof BigDecimal) {
            cell.setCellValue(obj.toString());
        }
    }
}