Question

    import java.io.File;
    import java.io.FileOutputStream;
    import java.io.IOException;
    import java.util.Arrays;
    import java.util.List;

    import javax.servlet.ServletException;
    import javax.servlet.http.HttpServlet;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;

    import org.apache.poi.hssf.usermodel.HSSFWorkbook;
    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.ss.usermodel.Workbook;
    import org.apache.poi.xssf.usermodel.XSSFWorkbook;

    public class ExcelWriter extends HttpServlet {
        private void writeExcel(List<Book> listBook, String excelFilePath)
                throws IOException {
            Workbook workbook = getWorkbook(excelFilePath);
            Sheet sheet = workbook.createSheet();

            int rowCount = 0;

            for (Book aBook : listBook) {
                Row row = sheet.createRow(++rowCount);
                writeBook(aBook, row);
            }

            try (FileOutputStream outputStream = new FileOutputStream(new File(
                    excelFilePath))) {
                workbook.write(outputStream);
            }
        }

        private void writeBook(Book aBook, Row row) {
            Cell cell = row.createCell(1);
            cell.setCellValue(aBook.getTitle());

            cell = row.createCell(2);
            cell.setCellValue(aBook.getAuthor());

            cell = row.createCell(3);
            cell.setCellValue(aBook.getPrice());
        }

        private List<Book> getListBook() {
            Book book1 = new Book("Head  Java", "Anot Serria", 79);
            Book book2 = new Book("Effective Java 1", "Bnot Bloch", 36);
            Book book3 = new Book("Clean Code 1", "Cnot Martin", 42);
            Book book4 = new Book("Thinking in Java 2", "D Eckel", 35);

            List<Book> listBook = Arrays.asList(book1, book2, book3, book4);

            return listBook;
        }

        private Workbook getWorkbook(String excelFilePath) throws IOException {
            Workbook workbook = null;

            if (excelFilePath.endsWith("xlsx")) {
                workbook = new XSSFWorkbook();
            } else if (excelFilePath.endsWith("xls")) {
                workbook = new HSSFWorkbook();
            } else {
                throw new IllegalArgumentException(
                        "The specified file is not Excel file");
            }

            return workbook;

        }

        public void doGet(HttpServletRequest request, HttpServletResponse response)
                throws ServletException, IOException {

            try {
                String excelFilePath = "C:\\Users\\A7369241\\Desktop\\Temp.xls";
                response.setContentType("application/octet-stream");
                response.setHeader("Content-Disposition", "attachment;filename="
                        + excelFilePath);
                ExcelWriter excelWriter = new ExcelWriter();
                List<Book> listBook = excelWriter.getListBook();
                excelWriter.writeExcel(listBook, excelFilePath);
                System.out.println("Excel file written successfully");
            } catch (Exception e) {
                System.out.println(e.getMessage());
            }
        }
    }

public class Book {
    private String title,author;
    private float price;
    public Book(String title, String author, float price) {
        super();
        this.title = title;
        this.author = author;
        this.price = price;
    }
    public String getTitle() {
        return title;
    }
    public void setTitle(String title) {
        this.title = title;
    }
    public String getAuthor() {
        return author;
    }
    public void setAuthor(String author) {
        this.author = author;
    }
    public float getPrice() {
        return price;
    }
    public void setPrice(float price) {
        this.price = price;
    }

}

因此，在ExcelWriter文件中，应按指定的路径在指定的文件路径下载该文件。浏览器中会生成一个弹出窗口，但是打开的Excel文件已损坏，并且不存储硬编码数据。另一方面，数据位于Excel文件中的指定位置，该位置不会显示在弹出窗口中，并且EXCEL文件处于兼容模式。

有人可以帮我吗？

Answer 1

尝试一下：

public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {

        try {
            ExcelWriter excelWriter = new ExcelWriter();
            List<Book> listBook = excelWriter.getListBook();
            excelWriter.writeExcel(listBook, excelFilePath);
            System.out.println("Excel file written successfully");

            String excelFilePath = "C:\\Users\\A7369241\\Desktop\\Temp.xls";
            response.setContentType("application/octet-stream");
            response.setHeader("Content-Disposition", "attachment;filename=temp.xls");

            OutputStream out = response.getOutputStream();
            try (FileInputStream in = new FileInputStream(file)) {
                byte[] buffer = new byte[4096];
                int length;
                while ((length = in.read(buffer)) > 0) {
                    out.write(buffer, 0, length);
                }
            }
            out.flush();

        } catch (Exception e) {
            System.out.println(e.getMessage());
        }
    }

如果您只想创建excel，则无需使用响应。并且文件名应为xlsx类型。这就是为什么您收到兼容模式消息的原因。

try {
            String excelFilePath = "C:\\Users\\A7369241\\Desktop\\Temp.xlsx";
            ExcelWriter excelWriter = new ExcelWriter();
            List<Book> listBook = excelWriter.getListBook();
            excelWriter.writeExcel(listBook, excelFilePath);
            System.out.println("Excel file written successfully");
        } catch (Exception e) {
            System.out.println(e.getMessage());
        }

如果仍然存在问题，则意味着servlet无法正常工作。只需尝试使用main方法和main方法类型创建类：

String excelFilePath = "D:\\Temp.xls";
Test excelWriter = new Test();
List<Book> listBook = excelWriter.getListBook();
try {
    excelWriter.writeExcel(listBook, excelFilePath);
    System.out.println("Excel file written successfully");
} catch (IOException e) {
    e.printStackTrace();
}

通过POI下载的文件已损坏，并且不通过弹出窗口存储数据

1 个答案: