Apache POI 4.0.1版本寫入普通Excel文件(兼容 xls 和 xlsx)(三)

基於最新的Apache POI 4.0.1版本來總結一下寫入Excel的過程。

代碼前准備：

添加4.0.1 poi maven依賴

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.springbootemaildemo</groupId>
    <artifactId>springboot-email-demo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>
    <name>springboot-email-demo</name>
    <description>Demo project for Spring Boot</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.6.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-mail</artifactId>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>io.springfox</groupId>
            <artifactId>springfox-swagger2</artifactId>
            <version>2.7.0</version>
        </dependency>
        <dependency>
            <groupId>io.springfox</groupId>
            <artifactId>springfox-swagger-ui</artifactId>
            <version>2.7.0</version>
        </dependency>

        <dependency>
            <groupId>org.jsoup</groupId>
            <artifactId>jsoup</artifactId>
            <version>1.11.3</version>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.41</version>
        </dependency>

        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-lang3</artifactId>
            <version>3.10</version>
        </dependency>

        <dependency>
            <groupId>commons-beanutils</groupId>
            <artifactId>commons-beanutils</artifactId>
            <version>1.8.3</version>
        </dependency>
        <dependency>
            <groupId>javax.persistence</groupId>
            <artifactId>persistence-api</artifactId>
            <version>1.0</version>
        </dependency>

<!--poi --> <dependency> <groupId>org.apache.poi</groupId> <artifactId>poi</artifactId> <version>4.0.1</version> </dependency> <dependency> <groupId>org.apache.poi</groupId> <artifactId>poi-ooxml</artifactId> <version>4.0.1</version> </dependency>

    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
</project>

DataVo（數據封裝類）

package com.springbootemaildemo.excel.b;

/**
 * 讀取Excel時，封裝讀取的每一行的數據
 */
public class DataVo {
    /**
     * 姓名
     */
    private String name;

    /**
     * 年齡
     */
    private Integer age;

    public String getName() {
        return name;
    }

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

    public Integer getAge() {
        return age;
    }

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

}

ExcelWriter（寫入excel文件主要代碼類）

package com.springbootemaildemo.excel.b;

import org.apache.poi.ss.usermodel.*;
import org.apache.poi.xssf.streaming.SXSSFWorkbook;

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

public class ExcelWriter {
    private static List<String> CELL_HEADS; //列頭

    static {
        // 類裝載時就載入指定好的列頭信息，如有需要，可以考慮做成動態生成的列頭
        CELL_HEADS = new ArrayList<>();
        CELL_HEADS.add("姓名");
        CELL_HEADS.add("年齡");
    }

    /**
     * 生成Excel並寫入數據信息
     *
     * @param dataList 數據列表
     * @return 寫入數據后的工作簿對象
     */
    public static Workbook exportData(List<DataVo> dataList) {
        // 生成xlsx的Excel
        Workbook workbook = new SXSSFWorkbook();

        // 如需生成xls的Excel，請使用下面的工作簿對象，注意后續輸出時文件后綴名也需更改為xls
        //Workbook workbook = new HSSFWorkbook();

        // 生成Sheet表，寫入第一行的列頭
        Sheet sheet = buildDataSheet(workbook);
        //構建每行的數據內容
        int rowNum = 1;
        for (Iterator<DataVo> it = dataList.iterator(); it.hasNext(); ) {
            DataVo data = it.next();
            if (data == null) {
                continue;
            }
            //輸出行數據
            Row row = sheet.createRow(rowNum++);
            convertDataToRow(data, row);
        }
        return workbook;
    }

    /**
     * 生成sheet表，並寫入第一行數據（列頭）
     *
     * @param workbook 工作簿對象
     * @return 已經寫入列頭的Sheet
     */
    private static Sheet buildDataSheet(Workbook workbook) {
        Sheet sheet = workbook.createSheet();
        // 設置列頭寬度
        for (int i = 0; i < CELL_HEADS.size(); i++) {
            sheet.setColumnWidth(i, 4000);
        }
        // 設置默認行高
        sheet.setDefaultRowHeight((short) 400);
        // 構建頭單元格樣式
        CellStyle cellStyle = buildHeadCellStyle(sheet.getWorkbook());
        // 寫入第一行各列的數據
        Row head = sheet.createRow(0);
        for (int i = 0; i < CELL_HEADS.size(); i++) {
            Cell cell = head.createCell(i);
            cell.setCellValue(CELL_HEADS.get(i));
            cell.setCellStyle(cellStyle);
        }
        return sheet;
    }

    /**
     * 設置第一行列頭的樣式
     *
     * @param workbook 工作簿對象
     * @return 單元格樣式對象
     */
    private static CellStyle buildHeadCellStyle(Workbook workbook) {
        CellStyle style = workbook.createCellStyle();
        //對齊方式設置
        style.setAlignment(HorizontalAlignment.CENTER);
        //邊框顏色和寬度設置
        style.setBorderBottom(BorderStyle.THIN);
        style.setBottomBorderColor(IndexedColors.BLACK.getIndex()); // 下邊框
        style.setBorderLeft(BorderStyle.THIN);
        style.setLeftBorderColor(IndexedColors.BLACK.getIndex()); // 左邊框
        style.setBorderRight(BorderStyle.THIN);
        style.setRightBorderColor(IndexedColors.BLACK.getIndex()); // 右邊框
        style.setBorderTop(BorderStyle.THIN);
        style.setTopBorderColor(IndexedColors.BLACK.getIndex()); // 上邊框
        //設置背景顏色
        style.setFillForegroundColor(IndexedColors.GREY_25_PERCENT.getIndex());
        style.setFillPattern(FillPatternType.SOLID_FOREGROUND);
        //粗體字設置
        Font font = workbook.createFont();
        font.setBold(true);
        style.setFont(font);
        return style;
    }

    /**
     * 將數據轉換成行
     *
     * @param data 源數據
     * @param row  行對象
     * @return
     */
    private static void convertDataToRow(DataVo data, Row row) {
        int cellNum = 0;
        Cell cell;
        // 姓名
        cell = row.createCell(cellNum++);
        cell.setCellValue(null == data.getName() ? "" : data.getName());
        // 年齡
        cell = row.createCell(cellNum++);
        if (null != data.getAge()) {
            cell.setCellValue(data.getAge());
        } else {
            cell.setCellValue("");
        }
    }
}

MyTest（測試類）

package com.springbootemaildemo.excel.b;

import org.apache.poi.ss.usermodel.Workbook;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

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

public class MyTest {
    private static final Logger logger = LoggerFactory.getLogger(MyTest.class);

    public static void main(String[] args) {
        // 創建需要寫入的數據列表
        List<DataVo> dataVOList = new ArrayList<>();
        DataVo dataVO = new DataVo();
        dataVO.setName("小明");
        dataVO.setAge(18);
        DataVo dataVO2 = new DataVo();
        dataVO2.setName("小花");
        dataVO2.setAge(19);
        dataVOList.add(dataVO);
        dataVOList.add(dataVO2);
        // 寫入數據到工作簿對象內
        Workbook workbook = ExcelWriter.exportData(dataVOList);
        // 以文件的形式輸出工作簿對象
        FileOutputStream fileOut = null;
        try {
            //E:\files\write-01.xlsx  不用創建，會自動生成的
            String exportFilePath = "E:\\files\\write-01.xlsx";
            File exportFile = new File(exportFilePath);
            if (!exportFile.exists()) {
                exportFile.createNewFile();
            }
            fileOut = new FileOutputStream(exportFilePath);
            workbook.write(fileOut);
            fileOut.flush();
        } catch (
                Exception e) {
            logger.warn("輸出Excel時發生錯誤，錯誤原因：" + e.getMessage());
        } finally {
            try {
                if (null != fileOut) {
                    fileOut.close();
                }
                if (null != workbook) {
                    workbook.close();
                }
            } catch (IOException e) {
                logger.warn("關閉輸出流時發生錯誤，錯誤原因：" + e.getMessage());
            }
        }
    }
}