EasyExcel自定义样式生成Excel

EasyExcel是一个基于Java的简单、省内存的读写excel的开源项目。在尽可能节约内存的情况下支持读写百M的excel.官方文档地址为：https://www.yuque.com/easyexcel/doc/easyexcel

 EasyExcel生成excel

1、定义实体类（模板）

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

@Data
public class StudentTable {

    @ColumnWidth(20)
    @ExcelProperty(value="姓名",index=0)
    private String studentName;

    @ColumnWidth(20)
    @ExcelProperty(value = "年龄",index = 1)
    private int studentAge;

    @ColumnWidth(20)
    @ExcelProperty(value = "年级",index = 2)
    private String studentGrade;

    @ColumnWidth(20)
    @ExcelProperty(value = "家庭住址",index = 3)
    private String studentAdress;
}

2、 excel生成方法

import com.alibaba.excel.EasyExcel;
import com.alibaba.excel.write.metadata.style.WriteCellStyle;
import com.alibaba.excel.write.metadata.style.WriteFont;
import com.alibaba.excel.write.style.HorizontalCellStyleStrategy;
import com.example.page.domain.StudentTable;
import com.example.page.utils.FileUtil;
import org.apache.poi.ss.usermodel.HorizontalAlignment;
import org.apache.poi.ss.usermodel.IndexedColors;
import org.apache.poi.ss.usermodel.VerticalAlignment;

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

/**
 * easyexcel生成excel
 */
public class StudentTableService {

    /**
     * 拦截器形式自定义样式
     */
    public static void ExcelWrite(List<StudentTable> list){
        //存储路径
        String fileName = FileUtil.getPath() + "student" + System.currentTimeMillis()+".xlsx";
        System.out.println(fileName);
        //设置excel的头策略
        WriteCellStyle headWriteCellStyle = new WriteCellStyle();
        //设置背景颜色
        headWriteCellStyle.setFillForegroundColor(IndexedColors.BLUE_GREY.getIndex());
        //设置字体大小
        WriteFont headWriteFont = new WriteFont();
        headWriteFont.setFontHeightInPoints((short)20);
        headWriteCellStyle.setWriteFont(headWriteFont);
        //设置内容策略
        WriteCellStyle contentWriteCellStyle = new WriteCellStyle();
        //设置字体
        WriteFont contentWriteFont = new WriteFont();
        contentWriteFont.setFontHeightInPoints((short)12);
        contentWriteCellStyle.setWriteFont(contentWriteFont);
        //设置自动换行
        contentWriteCellStyle.setWrapped(true);
        //设置垂直居中
        contentWriteCellStyle.setVerticalAlignment(VerticalAlignment.CENTER);
        //设置水平居中
        contentWriteCellStyle.setHorizontalAlignment(HorizontalAlignment.LEFT);
        //分别实现头和正文的样式
        HorizontalCellStyleStrategy horizontalCellStyleStrategy = new
                HorizontalCellStyleStrategy(headWriteCellStyle,contentWriteCellStyle);
        //这里需要指定用哪个class去写，然后写到第一个sheet上，名字为sheet1 然后文件流会自动关闭
        EasyExcel.write(fileName, StudentTable.class).registerWriteHandler(horizontalCellStyleStrategy).sheet("sheet1").doWrite(list);
    }

    public static List<StudentTable> data(){
        StudentTable studentTable = new StudentTable();
        List<StudentTable> list = new ArrayList<StudentTable>();
        //姓名
        studentTable.setStudentName("小明");
        //年龄
        studentTable.setStudentAge(10);
        //年级
        studentTable.setStudentGrade("三年级");
        //家庭住址
        studentTable.setStudentAdress("中国北京海淀区人民广场幸福里小区");
        list.add(studentTable);
        return list;
    }

    public static void main(String[] args){
        List<StudentTable> list = data();
        ExcelWrite(list);
    }
}

其中用到一个getPath()方法，该方法在FileUtil中定义

import java.io.File;
import java.io.InputStream;

public class FileUtil {

    public static InputStream getResourcesFileInputStream(String fileName){
        return Thread.currentThread().getContextClassLoader().getResourceAsStream(""+fileName);
    }

    public static String getPath(){
        return FileUtil.class.getResource("/").getPath();
    }

    public static File createNewFile(String pathName){
        File file = new File(getPath()+pathName);
        if (file.exists()){
            file.delete();
        }else{
            if(!file.getParentFile().exists()){
                file.getParentFile().mkdirs();
            }
        }
        return file;
    }

    public static File readFile(String pathName){
        return new File(getPath()+pathName);
    }

    public static File readUserHomeFile(String pathName){
        return new File(System.getProperty("user.home")+File.separator+pathName);
    }
}

在target/class目录下生成后的excel：