java中使用jxl匯出excel時，需指定WritableSheet物件中對應於每個單元格的資料。List型別是一種常用的資料型別，它裡面的元素是實體物件，當將它建立為WritableSheet物件時，它的每個實體元素可以通過簡單索引迴圈的形式遍歷到，但對實體每個屬性的遍歷，卻不能以簡單索引迴圈的形式實現，而只能用getter方法去逐一獲取，這樣，對不同的實體，均需特定的實現程式碼與之對應，勢必會造成大量的程式碼冗餘。
    一種有效的策略是，將List轉化為jsonArray，把實體物件的屬性名構造為一個字串陣列，那麼，只需使用該陣列的索引，對每個json物件迴圈訪問它的字串形式的鍵，便可完成對屬性值的遍歷。

示例：

實體類Student

public class Student {
    private String name;
    private String gender;
    private int age;

    public Student(String name, String gender, int age) {
        this.name = name;
        this.gender = gender;
        this.age = age;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getGender() {
        return gender;
    }

    public void setGender(String gender) {
        this.gender = gender;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }
}

 

JsonArray匯出為Exclel

import jxl.Workbook;
import jxl.write.Label;
import jxl.write.WritableSheet;
import jxl.write.WritableWorkbook;
import net.sf.json.JSONArray;
import net.sf.json.JSONObject;

import java.io.File;
import java.lang.reflect.Field;
import java.util.ArrayList;
import java.util.List;

public class JSONArrayToExcel {
    public static void main(String[] args) {

        Student student1 = new Student("張三","男",18);
        Student student2 = new Student("李四","男",19);
        Student student3 = new Student("小花","女",20);

        //實體List
        List<Student> studentList = new ArrayList<>();
        studentList.add(student1);
        studentList.add(student2);
        studentList.add(student3);

        //List轉為JSONArray
        JSONArray jsonArray = JSONArray.fromObject(studentList);

        //實體屬性名稱陣列
        Field[] fields = null;
        try {
            Class clazz = Class.forName("Student");
            fields = clazz.getDeclaredFields();
        }catch (Exception e){
            e.printStackTrace();
        }

        if (fields != null){
            String fileName = "jsonarrayToExcelTest.xls"; //檔名
            File myFile = new File("./"+fileName);

            try {
                WritableWorkbook writableWorkbook = Workbook.createWorkbook(myFile); //定義工作簿物件
                WritableSheet writableSheet = writableWorkbook.createSheet("sheet1",0); //定義sheet物件

                for (int i = 0; i < fields.length; i++) { //加入表頭單元格內容
                    writableSheet.addCell(new Label(i,0,fields[i].getName()));
                }

                for (int i = 0; i < jsonArray.size(); i++) { //加入資料單元格內容
                    JSONObject json = jsonArray.getJSONObject(i);
                    for (int j = 0; j < fields.length; j++) {
                        writableSheet.addCell(new Label(j,i+1,json.get(fields[j].getName()).toString()));
                    }
                }

                writableWorkbook.write();
                writableWorkbook.close();
            }catch (Exception e){
                e.printStackTrace();
            }

        }

    }
}

 

參考：

1. https://blog.csdn.net/Albert201605/article/details/120331212
2. https://blog.csdn.net/WangKun_0612/article/details/83618094
3. https://blog.csdn.net/qqllife/article/details/77237969?spm=1001.2101.3001.6650.10&utm_medium=distribute.pc_relevant.none-task-blog-2~default~CTRLIST~default-10.highlightwordscore&depth_1-utm_source=distribute.pc_relevant.none-task-blog-2~default~CTRLIST~default-10.highlightwordscore