導(dǎo)出的時(shí)候如果對(duì)Excel版本要求為xls版本時(shí)，大數(shù)據(jù)量時(shí)會(huì)比較慢逗柴，甚至出現(xiàn)內(nèi)存溢出蛹头，這里沒有去研究怎么實(shí)現(xiàn)xls實(shí)現(xiàn)大數(shù)據(jù)量導(dǎo)出，甚至輪子中連達(dá)到一定數(shù)量就新建sheet的操作都沒有戏溺，因?yàn)闆]有必要渣蜗，大數(shù)據(jù)我會(huì)選擇SXSSF導(dǎo)出。

當(dāng)導(dǎo)出為xlsx時(shí)旷祸，我沒有選擇用XSSF耕拷，而是選擇的SXSSF，這樣能減少內(nèi)存消耗托享，降低了內(nèi)存溢出的風(fēng)險(xiǎn)骚烧。

導(dǎo)出Excel輪子

package me.cf81.onestep.util;

import me.cf81.onestep.epc.Exceptions;
import org.apache.poi.hssf.usermodel.HSSFCellStyle;
import org.apache.poi.hssf.usermodel.HSSFFont;
import org.apache.poi.hssf.usermodel.HSSFPalette;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.*;
import org.apache.poi.ss.util.CellRangeAddress;
import org.apache.poi.xssf.streaming.SXSSFWorkbook;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.lang.reflect.Method;
import java.net.URLEncoder;
import java.text.DecimalFormat;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;

/**
 * @Author: yh
 * @Description: excel導(dǎo)出輪子
 * @Date: Created in 14:29  2018/11/27.
 */
public class ExcelExport {
    private static final Logger logger = LoggerFactory.getLogger(ExcelExport.class);
    HttpServletResponse response;
    // 文件名  
    private String fileName;
    //文件保存路徑  
    private String fileDir;
    //sheet名  
    private String sheetName;
    //表頭字體  
    private String titleFontType = "Arial Unicode MS";
    //表頭背景色  
    private String titleBackColor = "C1FBEE";
    //表頭字號(hào)  
    private short titleFontSize = 12;
    //添加自動(dòng)篩選的列 如 A:M  
    private String address = "";
    //正文字體  
    private String contentFontType = "Arial Unicode MS";
    //正文字號(hào)  
    private short contentFontSize = 12;
    //Float類型數(shù)據(jù)小數(shù)位  
    private String floatDecimal = "0.00";
    //Double類型數(shù)據(jù)小數(shù)位  
    private String doubleDecimal = "0.00";
    //設(shè)置列的公式  
    private String colFormula[] = null;

    DecimalFormat floatDecimalFormat = new DecimalFormat(floatDecimal);
    DecimalFormat doubleDecimalFormat = new DecimalFormat(doubleDecimal);

    private HSSFWorkbook workbook = null;

    public ExcelExport() {

    }

    public ExcelExport(String fileDir, String sheetName) {
        this.fileDir = fileDir;
        this.sheetName = sheetName;
        workbook = new HSSFWorkbook();
    }

    public ExcelExport(HttpServletResponse response, String fileName, String sheetName) {
        this.fileName = fileName;
        this.response = response;
        this.sheetName = sheetName;
        workbook = new HSSFWorkbook();
    }

    /**
     * 設(shè)置表頭字體.
     *
     * @param titleFontType
     */
    public void setTitleFontType(String titleFontType) {
        this.titleFontType = titleFontType;
    }

    /**
     * 設(shè)置表頭背景色.
     *
     * @param titleBackColor 十六進(jìn)制
     */
    public void setTitleBackColor(String titleBackColor) {
        this.titleBackColor = titleBackColor;
    }

    /**
     * 設(shè)置表頭字體大小.
     *
     * @param titleFontSize
     */
    public void setTitleFontSize(short titleFontSize) {
        this.titleFontSize = titleFontSize;
    }

    /**
     * 設(shè)置表頭自動(dòng)篩選欄位,如A:AC.
     *
     * @param address
     */
    public void setAddress(String address) {
        this.address = address;
    }

    /**
     * 設(shè)置正文字體.
     *
     * @param contentFontType
     */
    public void setContentFontType(String contentFontType) {
        this.contentFontType = contentFontType;
    }

    /**
     * 設(shè)置正文字號(hào).
     *
     * @param contentFontSize
     */
    public void setContentFontSize(short contentFontSize) {
        this.contentFontSize = contentFontSize;
    }

    /**
     * 設(shè)置float類型數(shù)據(jù)小數(shù)位 默認(rèn).00
     *
     * @param doubleDecimal 如 ".00"
     */
    public void setDoubleDecimal(String doubleDecimal) {
        this.doubleDecimal = doubleDecimal;
    }

    /**
     * 設(shè)置doubel類型數(shù)據(jù)小數(shù)位 默認(rèn).00
     *
     * @param floatDecimalFormat 如 ".00
     */
    public void setFloatDecimalFormat(DecimalFormat floatDecimalFormat) {
        this.floatDecimalFormat = floatDecimalFormat;
    }

    /**
     * 設(shè)置列的公式
     *
     * @param colFormula 存儲(chǔ)i-1列的公式 涉及到的行號(hào)使用@替換 如A@+B@
     */
    public void setColFormula(String[] colFormula) {
        this.colFormula = colFormula;
    }

    /**
     * 寫excel.
     * xls方式
     *
     * @param titleColumn 對(duì)應(yīng)bean的屬性名
     * @param titleName   excel要導(dǎo)出的列名
     * @param titleSize   列寬
     * @param dataList    數(shù)據(jù)
     */
    public void writeExcel(String titleColumn[], String titleName[], int titleSize[], List<?> dataList) {
        //添加Worksheet（不添加sheet時(shí)生成的xls文件打開時(shí)會(huì)報(bào)錯(cuò))  
        Sheet sheet = workbook.createSheet(this.sheetName);
        //新建文件  
        OutputStream out = null;
        try {
            if (fileDir != null) {
                //有文件路徑  
                out = new FileOutputStream(fileDir);
            } else {
                //否則，直接寫到輸出流中
                out = response.getOutputStream();
                fileName = fileName + ".xls";
                response.setContentType("application/msexcel;charset=UTF-8");
                response.setHeader("Content-Disposition", "attachment; filename="
                        + URLEncoder.encode(fileName, "UTF-8"));
            }

            //寫入excel的表頭  
            Row titleNameRow = workbook.getSheet(sheetName).createRow(0);
            //設(shè)置樣式  
            CellStyle titleStyle = workbook.createCellStyle();
            titleStyle = (HSSFCellStyle) setFontAndBorder(titleStyle, titleFontType, (short) titleFontSize);
            titleStyle = (HSSFCellStyle) setColor(titleStyle, titleBackColor, (short) 10);

            for (int i = 0; i < titleName.length; i++) {
                sheet.setColumnWidth(i, titleSize[i] * 256);    //設(shè)置寬度
                Cell cell = titleNameRow.createCell(i);
                cell.setCellStyle(titleStyle);
                cell.setCellValue(titleName[i].toString());
            }

            //為表頭添加自動(dòng)篩選  
            if (!"".equals(address)) {
                CellRangeAddress c = (CellRangeAddress) CellRangeAddress.valueOf(address);
                sheet.setAutoFilter(c);
            }

            //通過反射獲取數(shù)據(jù)并寫入到excel中  
            if (dataList != null && dataList.size() > 0) {
                //設(shè)置樣式  
                HSSFCellStyle dataStyle = workbook.createCellStyle();
                titleStyle = (HSSFCellStyle) setFontAndBorder(titleStyle, contentFontType, (short) contentFontSize);

                if (titleColumn.length > 0) {
                    for (int rowIndex = 1; rowIndex <= dataList.size(); rowIndex++) {
                        Object obj = dataList.get(rowIndex - 1);     //獲得該對(duì)象
                        Class clsss = obj.getClass();     //獲得該對(duì)對(duì)象的class實(shí)例  
                        Row dataRow = workbook.getSheet(sheetName).createRow(rowIndex);
                        for (int columnIndex = 0; columnIndex < titleColumn.length; columnIndex++) {
                            String title = titleColumn[columnIndex].toString().trim();
                            if (!"".equals(title)) {  //字段不為空
                                //使首字母大寫  
                                String UTitle = Character.toUpperCase(title.charAt(0)) + title.substring(1, title.length()); // 使其首字母大寫;
                                String methodName = "get" + UTitle;

                                // 設(shè)置要執(zhí)行的方法  
                                Method method = clsss.getDeclaredMethod(methodName);

                                //獲取返回類型  
                                String returnType = method.getReturnType().getName();
                                Object object = method.invoke(obj);
                                String data = method.invoke(obj) == null ? "" : object.toString();
                                Cell cell = dataRow.createCell(columnIndex);
                                if (data != null && !"".equals(data)) {
                                    if ("int".equals(returnType)) {
                                        cell.setCellValue(Integer.parseInt(data));
                                    } else if ("long".equals(returnType)) {
                                        cell.setCellValue(Long.parseLong(data));
                                    } else if ("float".equals(returnType)) {
                                        cell.setCellValue(floatDecimalFormat.format(Float.parseFloat(data)));
                                    } else if ("double".equals(returnType)) {
                                        cell.setCellValue(doubleDecimalFormat.format(Double.parseDouble(data)));
                                    } else if (Date.class.getName().equals(returnType)) {
                                        cell.setCellValue(new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(object));
                                    } else {
                                        cell.setCellValue(data);
                                    }
                                }
                            } else {   //字段為空 檢查該列是否是公式
                                if (colFormula != null) {
                                    String sixBuf = colFormula[columnIndex].replace("@", (rowIndex + 1) + "");
                                    Cell cell = dataRow.createCell(columnIndex);
                                    cell.setCellFormula(sixBuf);
                                }
                            }
                        }
                    }
                }
            }
            workbook.write(out);
        } catch (Exception e) {
            e.printStackTrace();
            throw Exceptions.ERROR.buildException();
        } finally {
            if (out != null) {
                try {
                    out.close();
                } catch (IOException e) {
                    logger.debug("導(dǎo)出寫Excel異常");
                }
            }
        }
    }


    /**
     * xlsx方式
     *
     * @param response
     * @param fileName
     * @param titleColumn
     * @param titleName
     * @param titleSize
     * @param dataList
     */
    public void writeBigExcel(HttpServletResponse response, String fileName, String titleColumn[],
                              String titleName[], int titleSize[], List<?> dataList) {
        try {
            SXSSFWorkbook workbook = new SXSSFWorkbook(100);
            OutputStream out = response.getOutputStream();
            String lastFileName = fileName + ".xlsx";
            response.setContentType("application/msexcel;charset=UTF-8");
            response.setHeader("Content-Disposition", "attachment; filename="
                    + URLEncoder.encode(lastFileName, "UTF-8"));
            int k = 0;
            int rowIndex;
            Sheet sheet = workbook.createSheet(fileName + (k + 1));
            //寫入excel的表頭
            Row titleNameRow = workbook.getSheet(fileName + (k + 1)).createRow(0);
            for (int i = 0; i < titleName.length; i++) {
                sheet.setColumnWidth(i, titleSize[i] * 256);    //設(shè)置寬度
                Cell cell = titleNameRow.createCell(i);
                cell.setCellValue(titleName[i]);
            }
            //寫入到excel中
            if (dataList != null && dataList.size() > 0) {
                if (titleColumn.length > 0) {
                    for (int index = 0; index < dataList.size(); index++) {
                        //每個(gè)sheet3W條數(shù)據(jù)
                        if (index != 0 && (index) % 30000 == 0) {
                            k = k + 1;
                            sheet = workbook.createSheet(fileName + (k + 1));
                            //寫入excel的表頭
                            titleNameRow = workbook.getSheet(fileName + (k + 1)).createRow(0);
                            for (int i = 0; i < titleName.length; i++) {
                                sheet.setColumnWidth(i, titleSize[i] * 256);    //設(shè)置寬度
                                Cell cell = titleNameRow.createCell(i);
                                cell.setCellValue(titleName[i]);
                            }
                        }
                        if (index < 30000) {
                            rowIndex = index + 1;
                        } else {
                            rowIndex = index - 30000 * ((index) / 30000) + 1;
                        }
                        Object obj = dataList.get(index);
                        Class clazz = obj.getClass();
                        Row dataRow = workbook.getSheet(fileName + (k + 1)).createRow(rowIndex);
                        for (int columnIndex = 0; columnIndex < titleColumn.length; columnIndex++) {
                            String title = titleColumn[columnIndex].trim();
                            if (!"".equals(title)) {
                                // 獲取返回類型
                                String UTitle = Character.toUpperCase(title.charAt(0)) + title.substring(1, title.length()); // 使其首字母大寫;
                                String methodName = "get" + UTitle;
                                Method method = clazz.getDeclaredMethod(methodName);
                                String returnType = method.getReturnType().getName();
                                Object object = method.invoke(obj);
                                String data = method.invoke(obj) == null ? "" : object.toString();
                                Cell cell = dataRow.createCell(columnIndex);
                                if (data != null && !"".equals(data)) {
                                    if ("int".equals(returnType)) {
                                        cell.setCellValue(Integer.parseInt(data));
                                    } else if ("long".equals(returnType)) {
                                        cell.setCellValue(Long.parseLong(data));
                                    } else if ("float".equals(returnType)) {
                                        cell.setCellValue(new DecimalFormat("0.00").format(Float.parseFloat(data)));
                                    } else if ("double".equals(returnType)) {
                                        cell.setCellValue(new DecimalFormat("0.00").format(Double.parseDouble(data)));
                                    } else if (Date.class.getName().equals(returnType)) {
                                        cell.setCellValue(new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(object));
                                    } else {
                                        cell.setCellValue(data);
                                    }
                                } else {   //字段為空 檢查該列是否是公式
                                    if (colFormula != null) {
                                        String sixBuf = colFormula[columnIndex].replace("@", (rowIndex + 1) + "");
                                        cell = dataRow.createCell(columnIndex);
                                        cell.setCellFormula(sixBuf);
                                    }
                                }
                            }
                        }
                    }
                }
            }
            workbook.write(out);
            out.flush();
            out.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * 將16進(jìn)制的顏色代碼寫入樣式中來設(shè)置顏色
     *
     * @param style 保證style統(tǒng)一
     * @param color 顏色：66FFDD
     * @param index 索引 8-64 使用時(shí)不可重復(fù)
     * @return
     */
    public CellStyle setColor(CellStyle style, String color, short index) {
        if ("".equals(color)) {
            //轉(zhuǎn)為RGB碼  
            int r = Integer.parseInt((color.substring(0, 2)), 16);   //轉(zhuǎn)為16進(jìn)制
            int g = Integer.parseInt((color.substring(2, 4)), 16);
            int b = Integer.parseInt((color.substring(4, 6)), 16);
            //自定義cell顏色  
            HSSFPalette palette = workbook.getCustomPalette();
            palette.setColorAtIndex((short) index, (byte) r, (byte) g, (byte) b);

            style.setFillPattern(FillPatternType.SOLID_FOREGROUND);
            style.setFillForegroundColor(index);
        }
        return style;
    }

    /**
     * 設(shè)置字體并加外邊框
     *
     * @param style 樣式
     * @param style 字體名
     * @param style 大小
     * @return
     */
    public CellStyle setFontAndBorder(CellStyle style, String fontName, short size) {
        HSSFFont font = workbook.createFont();
        font.setFontHeightInPoints(size);
        font.setFontName(fontName);
        font.setBold(true);
        style.setFont(font);
        style.setBorderBottom(BorderStyle.THIN); //下邊框
        style.setBorderLeft(BorderStyle.THIN);//左邊框
        style.setBorderTop(BorderStyle.THIN);//上邊框
        style.setBorderRight(BorderStyle.THIN);//右邊框
        return style;
    }
}

調(diào)用的例子

 /**
     * 保有量-導(dǎo)出Excel
     *
     * @param response
     */
    @Override
    public void exportInventoryResult(HttpServletResponse response, Map map, Long companyId) {
        List<InventoryDto> inventoryDtoList = inventoryMapper.selectExportInventoryResult(map, companyId);
        try {
            ExcelExport excelExport = new ExcelExport();
            excelExport.writeBigExcel(response, "保有量導(dǎo)出數(shù)據(jù)", new String[]{"materialCode", "materialName", "number", "countryArea"}
                    , new String[]{"物料號(hào)", "物料名稱", "數(shù)量", "國家大區(qū)"}
                    , new int[]{30, 30, 30, 30}, inventoryDtoList);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

/**
     * 導(dǎo)出Excel所有
     *
     * @param response
     */
    @Override
    public void exportExcel(HttpServletResponse response, Long companyId) {
        List<EpcSystemDictionary> epcSystemDictionaryList = epcSystemDictionaryMapper.getAll(companyId);
        ExcelExport excelExport = new ExcelExport(response, "數(shù)據(jù)字典總數(shù)據(jù)", "sheet1");
        excelExport.writeExcel(new String[]{"code", "name", "enName", "level", "sort"}
                , new String[]{"編號(hào)", "名稱", "英文名稱", "層級(jí)", "排序"}
                , new int[]{30, 30, 30, 30, 30}, epcSystemDictionaryList);
    }

? 其實(shí)代碼沒有很復(fù)雜闰围，也是比較簡單的赃绊。我遇到的難點(diǎn)就是分sheet的時(shí)候，就這么簡單的東西羡榴，算了接近兩個(gè)小時(shí)碧查，數(shù)學(xué)太差了。這一點(diǎn)似乎也沒有救了校仑。