Using Alibaba EasyExcel for Reading and Writing Excel Files in Java

The article introduces Alibaba's EasyExcel library as a high‑performance solution for Excel processing in Java backend applications.

Environment Setup : It lists the required Maven dependencies for easyexcel (mandatory) and optional lombok, showing the XML snippet for inclusion in pom.xml.

<dependency>
  <groupId>com.alibaba</groupId>
  <artifactId>easyexcel</artifactId>
  <version>1.1.2-beat1</version>
</dependency>

<dependency>
  <groupId>org.projectlombok</groupId>
  <artifactId>lombok</artifactId>
  <version>1.18.2</version>
</dependency>

Reading Excel Files (less than 1000 rows) : Demonstrates default and sheet‑specific reads using ExcelUtil.readLessThan1000Row(filePath) and ExcelUtil.readLessThan1000RowBySheet(filePath, sheet). Example code shows how to specify the file path and optional Sheet object.

String filePath = "/home/chenmingjian/Downloads/学生表.xlsx";
List<Object> objects = ExcelUtil.readLessThan1000Row(filePath);

Sheet sheet = new Sheet(1, 1); // sheet index, start row
List<Object> objects = ExcelUtil.readLessThan1000RowBySheet(filePath, sheet);

Reading Excel Files (more than 1000 rows) : Uses a streaming approach with ExcelUtil.readMoreThan1000Row and ExcelUtil.readMoreThan1000RowBySheet. A custom ExcelListener class implements AnalysisEventListener to collect rows.

String filePath = "/home/chenmingjian/Downloads/学生表.xlsx";
List<Object> objects = ExcelUtil.readMoreThan1000Row(filePath);

Sheet sheet = new Sheet(1, 2);
List<Object> objects = ExcelUtil.readMoreThan1000RowBySheet(filePath, sheet);

Exporting Excel – Single Sheet : Shows two ways to write data. (1) Simple export without model mapping using writeBySimple with a list of rows and a header list. (2) Export with model mapping using a POJO annotated with @ExcelProperty and writeWithTemplate.

// Simple export
String filePath = "/home/chenmingjian/Downloads/测试.xlsx";
List<List<Object>> data = new ArrayList<>();
data.add(Arrays.asList("111", "222", "333"));
List<String> head = Arrays.asList("表头1", "表头2", "表头3");
ExcelUtil.writeBySimple(filePath, data, head);

// Model‑based export
ArrayList<TableHeaderExcelProperty> data = new ArrayList<>();
for (int i = 0; i < 4; i++) {
    TableHeaderExcelProperty p = new TableHeaderExcelProperty();
    p.setName("cmj" + i);
    p.setAge(22 + i);
    p.setSchool("清华大学" + i);
    data.add(p);
}
ExcelUtil.writeWithTemplate(filePath, data);

Exporting Excel – Multiple Sheets : Defines a model class and uses ExcelUtil.writeWithMultipleSheel to generate a workbook containing several sheets, each with its own data list and Sheet configuration.

ArrayList<ExcelUtil.MultipleSheelPropety> list1 = new ArrayList<>();
for (int j = 1; j < 4; j++) {
    ArrayList<TableHeaderExcelProperty> list = new ArrayList<>();
    // fill list with model objects …
    Sheet sheet = new Sheet(j, 0);
    sheet.setSheetName("sheet" + j);
    ExcelUtil.MultipleSheelPropety prop = new ExcelUtil.MultipleSheelPropety();
    prop.setData(list);
    prop.setSheet(sheet);
    list1.add(prop);
}
ExcelUtil.writeWithMultipleSheel("/home/chenmingjian/Downloads/aaa.xlsx", list1);

Utility Class – ExcelUtil : Provides static methods for reading ( readLessThan1000Row, readMoreThan1000Row), writing ( writeBySimple, writeWithTemplate, writeWithMultipleSheel), and internal helpers such as sheet initialization, error handling, and resource cleanup.

Test Class : Contains JUnit test methods that demonstrate each read/write scenario, ensuring the utility works as expected in a Spring Boot context.

Overall, the guide serves as a ready‑to‑use reference for developers who need fast, memory‑efficient Excel I/O in backend Java applications.