Technical Details Analysis of Implementing Lightweight Excel Reader in Java Class Library
Technical Details Analysis of Implementing Lightweight Excel Reader in Java Class Library
In the actual development process, we often need to read data from Excel files. There are many mature Excel readers in the Java class library that can help us easily achieve this function. This article will analyze the technical details of implementing lightweight Excel readers in Java class libraries and provide corresponding Java code examples.
1、 Selection of Excel Reader
The commonly used Excel readers in Java class libraries include Apache POI, JExcel, EasyExcel, etc. This article will use Apache POI as an example to explain. Apache POI is a popular and powerful Java class library that can handle Microsoft Office format files, including Excel.
2、 Introducing Dependencies
Using Apache POI for Excel reading requires adding relevant dependencies to the project. In the Maven project, Apache POI can be introduced by adding the following dependencies in the pom.xml file:
<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi</artifactId>
<version>4.1.2</version>
</dependency>
<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi-ooxml</artifactId>
<version>4.1.2</version>
</dependency>
3、 Read Excel file
The main steps for using Apache POI to read Excel files are as follows:
1. Create a Workbook object for loading Excel files.
FileInputStream fileInputStream = new FileInputStream("path/to/excel/file.xlsx");
Workbook workbook = WorkbookFactory.create(fileInputStream);
2. Obtain the Sheet object that needs to be read.
Sheet sheet=workbook. getSheetAt (0)// Get the first sheet
3. Traverse each row and read the data for each column.
for (Row row : sheet) {
for (Cell cell : row) {
String cellValue=cell. getStringCellValue()// Read the text value of a cell
System.out.println(cellValue);
}
}
4、 Complete Example
The following is a complete Java code example that demonstrates how to use Apache POI to read data from an Excel file:
import org.apache.poi.ss.usermodel.*;
import java.io.FileInputStream;
import java.io.IOException;
public class ExcelReaderExample {
public static void main(String[] args) {
try {
FileInputStream fileInputStream = new FileInputStream("path/to/excel/file.xlsx");
Workbook workbook = WorkbookFactory.create(fileInputStream);
Sheet sheet = workbook.getSheetAt(0);
for (Row row : sheet) {
for (Cell cell : row) {
String cellValue = cell.getStringCellValue();
System.out.println(cellValue);
}
}
workbook.close();
fileInputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
Through the above code example, we can easily achieve the reading operation of Excel files.
Summary:
This article introduces the technical details of using Apache POI as a lightweight Excel reader in Java class libraries, and provides corresponding Java code examples. I hope readers can easily read Excel files through the introduction and sample code in this article.
