Spring Boot 数据导入导出与报表生成实战

应用配置

H2 内存数据库适合演示，配置简单。记得开启控制台以便调试。

server.port=8080
spring.datasource.url=jdbc:h2:mem:testdb
spring.datasource.driver-class-name=org.h2.Driver
spring.datasource.username=sa
spring.datasource.password=password
spring.jpa.hibernate.ddl-auto=update
spring.jpa.show-sql=true
spring.h2.console.enabled=true
spring.h2.console.path=/h2-console

实体与仓库层

定义一个产品实体，注意字段映射要准确。Repository 接口继承 JpaRepository 即可获得基础 CRUD 能力。

import javax.persistence.*;
import java.util.Objects;

@Entity
@Table(name = "product")
public class Product {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    private String productId;
    private String productName;
    private double price;
    private int sales;

    // 构造函数
    public Product() {}

    public Product(String productId, String productName, double price, int sales) {
        this.productId = productId;
        this.productName = productName;
        this.price = price;
        this.sales = sales;
    }

    // Getter 和 Setter
    public Long getId() { return id; }
    public void setId(Long id) { this.id = id; }
    public String getProductId() { return productId; }
    public void setProductId(String productId) { this.productId = productId; }
    public String getProductName() { return productName; }
    public void setProductName(String productName) { this.productName = productName; }
    public double getPrice() { return price; }
    public void setPrice(double price) { this.price = price; }
    public int getSales() { return sales; }
    public void setSales(int sales) { this.sales = sales; }

    @Override
    public String toString() {
        return "Product{" +
                "id=" + id +
                ", productId='" + productId + '\'' +
                ", productName='" + productName + '\'' +
                ", price=" + price +
                ", sales=" + sales +
                '}';
    }
}

业务逻辑实现

Service 层是核心。导入时需要注意跳过表头，导出时要设置列宽以便阅读。资源关闭（Workbook）务必放在 finally 块或使用 try-with-resources，防止内存泄漏。

import org.apache.poi.ss.usermodel.*;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.web.multipart.MultipartFile;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

@Service
public class ProductService {

    @Autowired
    private ProductRepository productRepository;

    @Transactional
    public void importProducts(MultipartFile file) throws IOException {
        List<Product> products = new ArrayList<>();
        Workbook workbook = null;
        try {
            workbook = new XSSFWorkbook(file.getInputStream());
            Sheet sheet = workbook.getSheetAt(0);
            Iterator<Row> iterator = sheet.iterator();
            if (iterator.hasNext()) {
                iterator.next(); // 跳过标题行
            }
            while (iterator.hasNext()) {
                Row currentRow = iterator.next();
                Product product = new Product();
                product.setProductId(currentRow.getCell(0).getStringCellValue());
                product.setProductName(currentRow.getCell(1).getStringCellValue());
                product.setPrice(currentRow.getCell(2).getNumericCellValue());
                product.setSales((int) currentRow.getCell(3).getNumericCellValue());
                products.add(product);
            }
            productRepository.saveAll(products);
        } finally {
            if (workbook != null) {
                workbook.close();
            }
        }
    }

    @Transactional(readOnly = true)
    public byte[] exportProducts() throws IOException {
        List<Product> products = productRepository.findAll();
        Workbook workbook = new XSSFWorkbook();
        Sheet sheet = workbook.createSheet("Products");

        Row headerRow = sheet.createRow(0);
        Cell headerCell0 = headerRow.createCell(0); headerCell0.setCellValue("Product ID");
        Cell headerCell1 = headerRow.createCell(1); headerCell1.setCellValue("Product Name");
        Cell headerCell2 = headerRow.createCell(2); headerCell2.setCellValue("Price");
        Cell headerCell3 = headerRow.createCell(3); headerCell3.setCellValue("Sales");

        int rowNum = 1;
        for (Product product : products) {
            Row row = sheet.createRow(rowNum++);
            row.createCell(0).setCellValue(product.getProductId());
            row.createCell(1).setCellValue(product.getProductName());
            row.createCell(2).setCellValue(product.getPrice());
            row.createCell(3).setCellValue(product.getSales());
        }

        // 自动调整列宽
        for (int i = 0; i < 4; i++) {
            sheet.autoSizeColumn(i);
        }

        ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
        workbook.write(outputStream);
        workbook.close();
        return outputStream.toByteArray();
    }

    @Transactional
    public Product addProduct(Product product) {
        return productRepository.save(product);
    }

    @Transactional(readOnly = true)
    public List<Product> getAllProducts() {
        return productRepository.findAll();
    }
}

控制器接口

Controller 负责接收请求并返回响应。导出时需要设置正确的 Content-Type 和 Content-Disposition 以触发浏览器下载。

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.web.bind.annotation.*;
import org.springframework.web.multipart.MultipartFile;

import java.io.IOException;
import java.util.List;

@RestController
@RequestMapping("/api/products")
public class ProductController {

    @Autowired
    private ProductService productService;

    @PostMapping("/import")
    public ResponseEntity<String> importProducts(@RequestParam("file") MultipartFile file) {
        try {
            productService.importProducts(file);
            return ResponseEntity.ok("数据导入成功");
        } catch (IOException e) {
            e.printStackTrace();
            return ResponseEntity.status(500).body("数据导入失败：" + e.getMessage());
        }
    }

    @GetMapping("/export")
    public ResponseEntity<byte[]> exportProducts() {
        try {
            byte[] bytes = productService.exportProducts();
            HttpHeaders headers = new HttpHeaders();
            headers.setContentType(MediaType.parseMediaType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"));
            headers.setContentDispositionFormData("attachment", "products.xlsx");
            headers.setCacheControl("must-revalidate, post-check=0, pre-check=0");
            return ResponseEntity.ok().headers(headers).body(bytes);
        } catch (IOException e) {
            e.printStackTrace();
            return ResponseEntity.status(500).body(null);
        }
    }

    @PostMapping("/")
    public Product addProduct(@RequestBody Product product) {
        return productService.addProduct(product);
    }

    @GetMapping("/")
    public List<Product> getAllProducts() {
        return productService.getAllProducts();
    }
}

使用 JasperReports 生成 PDF 报表

当需要生成固定格式的正式报表（如财务报表）时，Excel 可能不够美观，此时 JasperReports 是不错的选择。它支持复杂的布局设计和多种输出格式（PDF, HTML 等）。

依赖与模板

同样需要在 pom.xml 中添加 JasperReports 相关依赖。注意，JasperReports 通常需要预编译好的 .jasper 模板文件，或者在运行时加载 .jrxml 源码。

<dependency>
    <groupId>net.sf.jasperreports</groupId>
    <artifactId>jasperreports</artifactId>
    <version>6.17.0</version>
</dependency>
<dependency>
    <groupId>net.sf.jasperreports</groupId>
    <artifactId>jasperreports-fonts</artifactId>
    <version>6.17.0</version>
</dependency>

报表服务实现

Service 层负责加载模板、填充数据并导出为 PDF。这里假设模板文件位于 src/main/resources/reports/product-report.jasper。

import net.sf.jasperreports.engine.*;
import net.sf.jasperreports.engine.data.JRBeanCollectionDataSource;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.io.ByteArrayOutputStream;
import java.io.InputStream;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

@Service
public class ReportService {

    @Autowired
    private ProductRepository productRepository;

    public byte[] generateProductReport() throws JRException {
        List<Product> products = productRepository.findAll();
        InputStream templateStream = getClass().getResourceAsStream("/reports/product-report.jasper");
        JasperReport jasperReport = (JasperReport) JRLoader.loadObject(templateStream);

        Map<String, Object> parameters = new HashMap<>();
        parameters.put("Title", "产品销售报表");

        JRBeanCollectionDataSource dataSource = new JRBeanCollectionDataSource(products);
        JasperPrint jasperPrint = JasperFillManager.fillReport(jasperReport, parameters, dataSource);

        ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
        JasperExportManager.exportReportToPdfStream(jasperPrint, outputStream);
        return outputStream.toByteArray();
    }
}

报表接口

Controller 中增加一个端点来触发报表生成。

@GetMapping("/report")
public ResponseEntity<byte[]> generateProductReport() {
    try {
        byte[] bytes = reportService.generateProductReport();
        HttpHeaders headers = new HttpHeaders();
        headers.setContentType(MediaType.parseMediaType("application/pdf"));
        headers.setContentDispositionFormData("attachment", "product-report.pdf");
        headers.setCacheControl("must-revalidate, post-check=0, pre-check=0");
        return ResponseEntity.ok().headers(headers).body(bytes);
    } catch (JRException e) {
        e.printStackTrace();
        return ResponseEntity.status(500).body(null);
    }
}

实际应用场景总结

在实际项目中，这些功能通常组合使用。例如，允许管理员通过 Excel 批量更新库存，同时定期导出月度销售报表给财务部门。

• 产品信息管理：支持 Excel 导入导出，方便线下整理后批量入库。
• 用户信息管理：类似地用于会员数据迁移。
• 订单统计：结合 JasperReports 生成带图表的 PDF 订单汇总。

访问以下接口即可体验完整流程：

• GET /api/products/export：下载产品信息 Excel 文件。
• POST /api/products/import：上传产品信息 Excel 文件，导入数据。
• GET /api/products/report：下载产品销售报表（PDF 格式）。

开发建议

1. 异常处理：导入大文件时务必做好事务管理和资源释放，避免 OOM。
2. 权限控制：导入导出接口涉及敏感数据，记得加上 Spring Security 拦截。
3. 异步处理：如果数据量超过万条，建议将导入导出改为异步任务，避免阻塞主线程。
4. 模板维护：JasperReports 的模板修改较为复杂，建议建立专门的模板设计流程。