简单导出更新版---详细

1.导入依赖

<!--easy-poi-->
<dependency>
    <groupId>cn.afterturn</groupId>
    <artifactId>easypoi-spring-boot-starter</artifactId>
    <version>4.3.0</version>
</dependency>
2.编写一个导出的类的方法

package com.jx.util.api.util;
import cn.afterturn.easypoi.excel.ExcelExportUtil;
import cn.afterturn.easypoi.excel.entity.ExportParams;
import org.apache.poi.ss.usermodel.Workbook;
import org.springframework.stereotype.Component;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.ByteArrayOutputStream;
import java.net.URLEncoder;
import java.util.List;

@Component
public class MyExcelImportUtil {


    /**
     * 简单导出数据
     * @param tage 导出的表的名称
     * @param list 要导出的数据
     * @param t 导出表的实体
     * @param response 响应流
     * @param <T>
     * @throws Exception
     */
    public static <T> void simplyExportExcel(String tage,List<T> list, T t, HttpServletResponse response) throws Exception {
        ExportParams params = new ExportParams();
        params.setSheetName(tage);
        params.setStyle(ExcelStyleUtil.class);
        Workbook workbook = ExcelExportUtil.exportExcel(params, t.getClass(), list);

        // 设置响应的ContentType和Header，告诉浏览器下载文件
        response.setContentType("application/vnd.ms-excel");
        response.setHeader("Access-Control-Expose-Headers","Content-Disposition");
        response.setHeader("Content-Disposition", "attachment;filename=" + URLEncoder.encode(tage+".xls", "UTF-8"));


        ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
        workbook.write(byteArrayOutputStream);
        byte[] bytes = byteArrayOutputStream.toByteArray();

        ServletOutputStream servletOutputStream = response.getOutputStream();

        int bufferSize = 1024 * 1024; // 1 兆字节
        int offset = 0;

        while (offset < bytes.length) {
            int remaining = bytes.length - offset;
            int chunkSize = Math.min(remaining, bufferSize);
            servletOutputStream.write(bytes, offset, chunkSize);
            offset += chunkSize;
            servletOutputStream.flush();
        }

        servletOutputStream.close();
    }
}
额外附加处理样式的类

package com.jx.util.api.util;

import cn.afterturn.easypoi.excel.entity.params.ExcelExportEntity;
import cn.afterturn.easypoi.excel.entity.params.ExcelForEachParams;
import cn.afterturn.easypoi.excel.export.styler.IExcelExportStyler;
import org.apache.poi.ss.usermodel.*;

/**
 * @author 丁庆洋
 */
public class ExcelStyleUtil implements IExcelExportStyler {
    private static final short STRING_FORMAT = (short) BuiltinFormats.getBuiltinFormat("TEXT");
    private static final short FONT_SIZE_TEN = 11;
    private static final short FONT_SIZE_ELEVEN = 13;
    private static final short FONT_SIZE_TWELVE = 10;
    /**
     * 大标题样式
     */
    private CellStyle headerStyle;
    /**
     * 每列标题样式
     */
    private CellStyle titleStyle;
    /**
     * 数据行样式
     */
    private CellStyle styles;

    public ExcelStyleUtil(Workbook workbook) {
        this.init(workbook);
    }

    /**
     * 初始化样式
     *
     * @param workbook
     */
    private void init(Workbook workbook) {
        this.headerStyle = initHeaderStyle(workbook);
        this.titleStyle = initTitleStyle(workbook);
        this.styles = initStyles(workbook);
    }

    /**
     * 大标题样式
     *
     * @param color
     * @return
     */
    @Override
    public CellStyle getHeaderStyle(short color) {
        return headerStyle;
    }

    /**
     * 每列标题样式
     *
     * @param color
     * @return
     */
    @Override
    public CellStyle getTitleStyle(short color) {
        return titleStyle;
    }

    /**
     * 数据行样式
     *
     * @param parity 可以用来表示奇偶行
     * @param entity 数据内容
     * @return 样式
     */
    @Override
    public CellStyle getStyles(boolean parity, ExcelExportEntity entity) {
        return styles;
    }

    /**
     * 获取样式方法
     *
     * @param dataRow 数据行
     * @param obj     对象
     * @param data    数据
     */
    @Override
    public CellStyle getStyles(Cell cell, int dataRow, ExcelExportEntity entity, Object obj, Object data) {
        return getStyles(true, entity);
    }

    /**
     * 模板使用的样式设置
     */
    @Override
    public CellStyle getTemplateStyles(boolean isSingle, ExcelForEachParams excelForEachParams) {
        return null;
    }

    /**
     * 初始化--大标题样式
     *
     * @param workbook
     * @return
     */
    private CellStyle initHeaderStyle(Workbook workbook) {
        CellStyle style = getBaseCellStyle(workbook);
        Font font = getFont(workbook, FONT_SIZE_TWELVE, true);
        font.setColor(Font.COLOR_RED);
        style.setFont(font);
        return style;
    }

    /**
     * 初始化--每列标题样式
     *
     * @param workbook
     * @return
     */
    private CellStyle initTitleStyle(Workbook workbook) {
        CellStyle style = getBaseCellStyle(workbook);
        style.setFont(getFont(workbook, FONT_SIZE_ELEVEN, true));
        //背景色
        style.setFillForegroundColor(IndexedColors.GREY_25_PERCENT.getIndex());
        style.setFillPattern(FillPatternType.SOLID_FOREGROUND);
        return style;
    }

    /**
     * 初始化--数据行样式
     *
     * @param workbook
     * @return
     */
    private CellStyle initStyles(Workbook workbook) {
        CellStyle style = getBaseCellStyle(workbook);
        style.setFont(getFont(workbook, FONT_SIZE_TEN, false));
        style.setDataFormat(STRING_FORMAT);
        return style;
    }

    /**
     * 基础样式
     *
     * @return
     */
    private CellStyle getBaseCellStyle(Workbook workbook) {
        CellStyle style = workbook.createCellStyle();
        //下边框
        style.setBorderBottom(BorderStyle.THIN);
        //左边框
        style.setBorderLeft(BorderStyle.THIN);
        //上边框
        style.setBorderTop(BorderStyle.THIN);
        //右边框
        style.setBorderRight(BorderStyle.THIN);
        //水平居中
        style.setAlignment(HorizontalAlignment.CENTER);
        //上下居中
        style.setVerticalAlignment(VerticalAlignment.CENTER);
        //设置自动换行
        style.setWrapText(false);
        return style;
    }

    /**
     * 字体样式
     *
     * @param size   字体大小
     * @param isBold 是否加粗
     * @return
     */
    private Font getFont(Workbook workbook, short size, boolean isBold) {
        Font font = workbook.createFont();
        //字体样式
        font.setFontName("宋体");
        //是否加粗
        font.setBold(isBold);
        //字体大小
        font.setFontHeightInPoints(size);
        return font;
    }
}

3.接下来就是正式开始处理数据
（1）对导出的实体进行处理

 时间的格式一样要注意 格式不对 会导致 解析错误 导出不合理的数据

 一定记得加produces="application/octet-stream" 切记！！！！！！！

 处理数据 如果想要文字 进行封装方法处理 

 当查询条件是ids时 用

  来处理

 这是用的时候注意事项

还有就是如果入参是多个id的时候 用post请求来写 要不前端笨比不好处理