java 导出多个发票格式excel的代码

好的，下面是一个简单的Java代码示例，可以实现导出多个发票格式的Excel文件。

import java.io.FileOutputStream;
import java.util.ArrayList;
import java.util.List;

import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

public class InvoiceExporter {
    
    public static void main(String[] args) {
        // 创建需要导出的发票数据
        List<Invoice> invoices = createInvoices();
        
        // 导出Excel文件
        try (XSSFWorkbook workbook = new XSSFWorkbook()) {
            // 创建新的工作表
            Sheet sheet = workbook.createSheet("发票列表");
            
            // 创建表头行
            Row headerRow = sheet.createRow(0);
            Cell cell = headerRow.createCell(0);
            cell.setCellValue("发票号码");
            cell = headerRow.createCell(1);
            cell.setCellValue("客户名称");
            cell = headerRow.createCell(2);
            cell.setCellValue("发票金额");
            
            // 填充数据行
            int rowNum = 1;
            for (Invoice invoice : invoices) {
                Row row = sheet.createRow(rowNum++);
                row.createCell(0).setCellValue(invoice.getNumber());
                row.createCell(1).setCellValue(invoice.getCustomer());
                row.createCell(2).setCellValue(invoice.getAmount());
            }
            
            // 将数据写入Excel文件
            FileOutputStream outputStream = new FileOutputStream("invoices.xlsx");
            workbook.write(outputStream);
            workbook.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
    
    // 创建发票数据
    private static List<Invoice> createInvoices() {
        List<Invoice> invoices = new ArrayList<>();
        invoices.add(new Invoice("001", "客户A", 1000));
        invoices.add(new Invoice("002", "客户B", 2000));
        invoices.add(new Invoice("003", "客户C", 3000));
        return invoices;
    }
    
    // 发票类
    private static class Invoice {
        private String number;
        private String customer;
        private double amount;
        
        public Invoice(String number, String customer, double amount) {
            this.number = number;
            this.customer = customer;
            this.amount = amount;
        }
        
        public String getNumber() {
            return number;
        }
        
        public String getCustomer() {
            return customer;
        }
        
        public double getAmount() {
            return amount;
        }
    }

}

这个示例程序创建了一个包含3个发票的列表，并将列表中的发票信息导出为一个Excel文件。你可以根据需要修改代码，实现更加复杂的发票导出功能。