Java+EasyExcel实现文件的导入导出

<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>easyexcel</artifactId>
    <version>2.1.6</version>
</dependency>

package com.wanshi.spring.entity;

import com.alibaba.excel.annotation.ExcelIgnore;
import com.alibaba.excel.annotation.ExcelProperty;
import com.alibaba.excel.annotation.write.style.ColumnWidth;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

@Data
@NoArgsConstructor
@AllArgsConstructor
public class Employee {

    @ExcelIgnore
    private String noid;

    @ColumnWidth(20)
    @ExcelProperty("员工姓名")
    private String emp_name;

    @ColumnWidth(20)
    @ExcelProperty("员工年龄")
    private Integer emp_age;

    @ExcelIgnore
    private Integer emp_sex;

    //冗余字段
    @ColumnWidth(20)
    @ExcelProperty("员工性别")
    private String str_emp_sex;

    @ColumnWidth(20)
    @ExcelProperty("员工工资")
    private Double emp_salary;

    @ColumnWidth(20)
    @ExcelProperty("员工住址")
    private String emp_address;

    @ColumnWidth(20)
    @ExcelProperty("员工岗位")
    private String emp_position;

    //分页相关，当前页与每页的数据条数
    @ExcelIgnore
    private Integer pageNum;
    @ExcelIgnore
    private Integer pageSize;
}

package com.wanshi.spring.listener;

import com.alibaba.excel.context.AnalysisContext;
import com.alibaba.excel.event.AnalysisEventListener;
import com.wanshi.spring.entity.Employee;

import java.util.ArrayList;
import java.util.List;

public class EmployeeReadListener extends AnalysisEventListener<Employee> {

    //员工集合
    private static List<Employee> employeeList = new ArrayList<>();

    // 每读一样，会调用该invoke方法一次
    @Override
    public void invoke(Employee data, AnalysisContext context) {
        employeeList.add(data);
        System.out.println("解析到一条数据：" + data);
    }

    // 全部读完之后，会调用该方法
    @Override
    public void doAfterAllAnalysed(AnalysisContext context) {
        System.out.println("全部解析完成");
    }

    /**
     * 返回读取到的员工集合
     * @return
     */
    public static List<Employee> getStudentList() {
        return employeeList;
    }
}

@Test
public void test1(){
    ExcelReaderBuilder workBook = EasyExcel.read
        ("C:\\Users\\王会称\\Desktop\\员工.xlsx", Employee.class, new EmployeeReadListener());

    // 封装工作表
    ExcelReaderSheetBuilder sheet1 = workBook.sheet();
    // 读取
    sheet1.doRead();

    //写入数据库
    List<Employee> studentList = EmployeeReadListener.getStudentList();
    for (Employee employee : studentList) {
        employee.setNoid(PbSecretUtils.uuid());
        employeeMapper.insert(employee);
    }
}

@PostMapping("/import_employee_excel")
public String importEmployeeExcel(MultipartFile emp_excel) {
    employeeService.importExcel(emp_excel);
    return "redirect:/employee/list";
}

/**
     * 获取用户选择的文件并将文件存入指定位置再将数据存入数据库
     * @param emp_excel
     * @return
     */
public Integer importExcel(MultipartFile emp_excel) {
    try {
        String fileName = FileUploadUtil.upload(emp_excel, "");
        ExcelReaderBuilder workBook = EasyExcel.read
            (GlobalSet.upload_url+fileName, Employee.class, new EmployeeReadListener());

        // 封装工作表
        ExcelReaderSheetBuilder sheet1 = workBook.sheet();
        // 读取
        sheet1.doRead();

        List<Employee> studentList = EmployeeReadListener.getStudentList();
        for (Employee employee : studentList) {
            employee.setNoid(PbSecretUtils.uuid());
            if ("男".equals(employee.getStr_emp_sex())) {
                employee.setEmp_sex(1);
            } else {
                employee.setEmp_sex(2);
            }
            employeeMapper.insert(employee);
        }
    } catch (IOException e) {
        e.printStackTrace();
    }
    return 0;
}

@Test
public void test2() throws FileNotFoundException {

    List<Employee> employeeList = initData();


    ExcelWriterBuilder workBook = EasyExcel.write(GlobalSet.download_url, Employee.class);

    // sheet方法参数： 工作表的顺序号（从0开始）或者工作表的名字
    workBook.sheet("测试数据表").doWrite(employeeList);
    System.out.println("写入完成！");
}

/**
     * 生成测试数据
     * @return
     */
public List<Employee> initData() {
    List<Employee> employeeList = new ArrayList<>();
    for (int i = 1; i < 100; i++) {
        Employee employee = new Employee();
        employee.setEmp_name("小王说："+i);
        employee.setEmp_age(19);
        if (i % 10 == 0) {
            employee.setEmp_sex(1);
        } else {
            employee.setEmp_sex(2);
        }
        employee.setEmp_salary(19999.00+i);
        employee.setEmp_address("北京市朝阳区"+i);
        employee.setEmp_position("Java高级工程师");
        employeeList.add(employee);
    }
    return employeeList;
}

@GetMapping("/export_employee_excel")
    public void exportEmployeeExcel(HttpServletResponse response) {
        try {
            employeeService.exportEmployeeExcel(response);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

public void exportEmployeeExcel(HttpServletResponse response) throws IOException {
        List<Employee> kspwStudentSeatList = list();
        try {
            ExcelWriterBuilder workBook = EasyExcel.write(GlobalSet.download_url, Employee.class);
            // sheet方法参数： 工作表的顺序号（从0开始）或者工作表的名字
            workBook.sheet("员工信息").doWrite(kspwStudentSeatList);
            downloadTempalate(response);
            System.out.println("写入完成！");
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * 下载文件
     * @param response
     * @throws IOException
     */
    public static void downloadTempalate(HttpServletResponse response) throws IOException {
        // 告诉浏览器用什么软件可以打开此文件
        response.setHeader("content-Type", "application/vnd.ms-excel");
        // 下载文件的默认名称
        response.setHeader("Content-Disposition", "attachment;filename=" + URLEncoder.encode("员工信息.xlsx", "utf-8"));
        //4. 创建输入、输出流
        FileInputStream input = new FileInputStream(GlobalSet.download_url);
        ServletOutputStream sos = response.getOutputStream();

        //IO流获取文件的字节流，然后再响应给浏览器
        byte[] arr = new byte[1024];
        int res = 0;
        while((res = input.read(arr)) > 0){
            //将读取的内容输出到输出流中
            sos.write(arr, 0, res);
        }

        input.close();
        sos.close();
    }