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  • java实现Excel数据导出

    java实现Excel数据导出:

         目前,比较常用的实现Java导入、导出Excel的技术有两种Jakarta POI和Java Excel

    Jakarta POI 是一套用于访问微软格式文档的Java API。Jakarta POI有很多组件组成,其中有用于操作Excel格式文件的HSSF和用于操作Word的HWPF,在各种组件中目前只有用于操作Excel的HSSF相对成熟。官方主页http://poi.apache.org/index.html,API文档http://poi.apache.org/apidocs/index.html

    Jakarta POI HSSF API组件

    HSSF(用于操作Excel的组件)提供给用户使用的对象在rg.apache.poi.hssf.usermodel包中,主要部分包括Excel对象,样式和格式,还有辅助操作。有以下几种对象: 

    2.3 基本操作步骤

    首先,理解一下一个Excel的文件的组织形式,一个Excel文件对应于一个workbook(HSSFWorkbook),一个workbook可以有多个sheet(HSSFSheet)组成,一个sheet是由多个row(HSSFRow)组成,一个row是由多个cell(HSSFCell)组成。

    基本操作步骤:

     下面来看一个动态生成Excel文件的例子:

     1 //创建HSSFWorkbook对象
     2 HSSFWorkbook wb = new HSSFWorkbook();
     3 //创建HSSFSheet对象
     4 HSSFSheet sheet = wb.createSheet("sheet0");
     5 //创建HSSFRow对象
     6 HSSFRow row = sheet.createRow(0);
     7 //创建HSSFCell对象
     8 HSSFCell cell=row.createCell(0);
     9 //设置单元格的值
    10 cell.setCellValue("单元格中的中文");
    11 //输出Excel文件
    12 FileOutputStream output=new FileOutputStream("d:\workbook.xls");
    13 wkb.write(output);
    14 output.flush();

          HSSF读取文件同样还是使用这几个对象,只是把相应的createXXX方法变成了getXXX方法即可。可见只要理解了其中原理,不管是读还是写亦或是特定格式都可以轻松实现,正所谓知其然更要知其所以然。

     2:导出Excel应用实例:

     <!--导出文件-->
            <dependency>
                <groupId>org.apache.poi</groupId>
                <artifactId>poi</artifactId>
                <version>3.17</version>
            </dependency>
            <dependency>
                <groupId>org.apache.poi</groupId>
                <artifactId>poi-ooxml</artifactId>
                <version>3.17</version>
            </dependency>
            <dependency>
                <groupId>commons-io</groupId>
                <artifactId>commons-io</artifactId>
                <version>2.4</version>
            </dependency>

     3:导出表格的工具类:

    excelUtil:  

    package com.zhl.push.Utils;
    
    import com.google.common.base.Strings;
    import org.apache.poi.hssf.usermodel.*;
    import org.apache.poi.hssf.util.HSSFColor;
    import org.apache.poi.ss.usermodel.VerticalAlignment;
    import org.apache.poi.ss.util.CellRangeAddress;
    
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    import java.io.IOException;
    import java.io.OutputStream;
    import java.math.BigDecimal;
    import java.util.List;
    import java.util.Map;
    
    public class ExcelExportUtil {
        //表头
        private String title;
        //各个列的表头
        private String[] heardList;
        //各个列的元素key值
        private String[] heardKey;
        //需要填充的数据信息
        private List<Map> data;
        //字体大小
        private int fontSize = 14;
        //行高
        private int rowHeight = 30;
        //列宽
        private int columWidth = 200;
        //工作表
        private String sheetName = "sheet1";
    
        public String getTitle() {
            return title;
        }
    
        public void setTitle(String title) {
            this.title = title;
        }
    
        public String[] getHeardList() {
            return heardList;
        }
    
        public void setHeardList(String[] heardList) {
            this.heardList = heardList;
        }
    
        public String[] getHeardKey() {
            return heardKey;
        }
    
        public void setHeardKey(String[] heardKey) {
            this.heardKey = heardKey;
        }
    
        public List<Map> getData() {
            return data;
        }
    
        public void setData(List<Map> data) {
            this.data = data;
        }
    
        public int getFontSize() {
            return fontSize;
        }
    
        public void setFontSize(int fontSize) {
            this.fontSize = fontSize;
        }
    
        public int getRowHeight() {
            return rowHeight;
        }
    
        public void setRowHeight(int rowHeight) {
            this.rowHeight = rowHeight;
        }
    
        public int getColumWidth() {
            return columWidth;
        }
    
        public void setColumWidth(int columWidth) {
            this.columWidth = columWidth;
        }
    
        public String getSheetName() {
            return sheetName;
        }
    
        public void setSheetName(String sheetName) {
            this.sheetName = sheetName;
        }
    
        /**
         * 开始导出数据信息
         *
         */
        public byte[] exportExport(HttpServletRequest request, HttpServletResponse response) throws IOException {
            //检查参数配置信息
            checkConfig();
            //创建工作簿
            HSSFWorkbook wb = new HSSFWorkbook();
            //创建工作表
            HSSFSheet wbSheet = wb.createSheet(this.sheetName);
            //设置默认行宽
            wbSheet.setDefaultColumnWidth(20);
    
            // 标题样式(加粗,垂直居中)
            HSSFCellStyle cellStyle = wb.createCellStyle();
            cellStyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);//水平居中
            cellStyle.setVerticalAlignment(VerticalAlignment.CENTER);//垂直居中
            HSSFFont fontStyle = wb.createFont();
            fontStyle.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
            fontStyle.setBold(true);   //加粗
            fontStyle.setFontHeightInPoints((short)16);  //设置标题字体大小
            cellStyle.setFont(fontStyle);
    
            //在第0行创建rows  (表标题)
            HSSFRow title = wbSheet.createRow((int) 0);
            title.setHeightInPoints(30);//行高
            HSSFCell cellValue = title.createCell(0);
            cellValue.setCellValue(this.title);
            cellValue.setCellStyle(cellStyle);
            wbSheet.addMergedRegion(new CellRangeAddress(0,0,0,(this.heardList.length-1)));
            //设置表头样式,表头居中
            HSSFCellStyle style = wb.createCellStyle();
            //设置单元格样式
            style.setAlignment(HSSFCellStyle.ALIGN_CENTER);
            style.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);
            //设置字体
            HSSFFont font = wb.createFont();
            font.setFontHeightInPoints((short) this.fontSize);
            style.setFont(font);
            //在第1行创建rows
            HSSFRow row = wbSheet.createRow((int) 1);
            //设置列头元素
            HSSFCell cellHead = null;
            for (int i = 0; i < heardList.length; i++) {
                cellHead = row.createCell(i);
                cellHead.setCellValue(heardList[i]);
                cellHead.setCellStyle(style);
            }
    
            //设置每格数据的样式 (字体红色)
            HSSFCellStyle cellParamStyle = wb.createCellStyle();
            HSSFFont ParamFontStyle = wb.createFont();
            cellParamStyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);
            cellParamStyle.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);
            ParamFontStyle.setColor(HSSFColor.DARK_RED.index);   //设置字体颜色 (红色)
            ParamFontStyle.setFontHeightInPoints((short) this.fontSize);
            cellParamStyle.setFont(ParamFontStyle);
            //设置每格数据的样式2(字体蓝色)
            HSSFCellStyle cellParamStyle2 = wb.createCellStyle();
            cellParamStyle2.setAlignment(HSSFCellStyle.ALIGN_CENTER);
            cellParamStyle2.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);
            HSSFFont ParamFontStyle2 = wb.createFont();
            ParamFontStyle2.setColor(HSSFColor.BLUE.index);   //设置字体颜色 (蓝色)
            ParamFontStyle2.setFontHeightInPoints((short) this.fontSize);
            cellParamStyle2.setFont(ParamFontStyle2);
            //开始写入实体数据信息
            int a = 2;
            for (int i = 0; i < data.size(); i++) {
                HSSFRow roww = wbSheet.createRow((int) a);
                Map map = data.get(i);
                HSSFCell cell = null;
                for (int j = 0; j < heardKey.length; j++) {
                    cell = roww.createCell(j);
                    cell.setCellStyle(style);
                    Object valueObject = map.get(heardKey[j]);
                    String value = null;
                    if (valueObject == null) {
                        valueObject = "";
                    }
                    if (valueObject instanceof String) {
                        //取出的数据是字符串直接赋值
                        value = (String) map.get(heardKey[j]);
                    } else if (valueObject instanceof Integer) {
                        //取出的数据是Integer
                        value = String.valueOf(((Integer) (valueObject)).floatValue());
                    } else if (valueObject instanceof BigDecimal) {
                        //取出的数据是BigDecimal
                        value = String.valueOf(((BigDecimal) (valueObject)).floatValue());
                    } else {
                        value = valueObject.toString();
                    }
                    //设置单个单元格的字体颜色
                    if(heardKey[j].equals("ddNum") || heardKey[j].equals("sjNum")){
                    if((Long)map.get("ddNum")!=null){
                        if((Long)map.get("sjNum")==null){
                            cell.setCellStyle(cellParamStyle);
                        } else if((Long) map.get("ddNum") != (Long) map.get("sjNum")){
                            if ((Long) map.get("ddNum") > (Long) map.get("sjNum")) {
                                cell.setCellStyle(cellParamStyle);
                            }
                            if ((Long) map.get("ddNum") < (Long) map.get("sjNum")) {
                                cell.setCellStyle(cellParamStyle2);
                            }
                        }else {
                            cell.setCellStyle(style);
                        }
                    }
                    }
                    cell.setCellValue(Strings.isNullOrEmpty(value) ? "" : value);
                }
                a++;
            }
    
            //导出数据
            try {
                //设置Http响应头告诉浏览器下载这个附件
                response.setHeader("Content-Disposition", "attachment;Filename=" + System.currentTimeMillis() + ".xls");
                OutputStream outputStream = response.getOutputStream();
                wb.write(outputStream);
                outputStream.close();
                return wb.getBytes();
            } catch (Exception ex) {
                ex.printStackTrace();
                throw new IOException("导出Excel出现严重异常,异常信息:" + ex.getMessage());
            }
    
        }
    
        /**
         * 检查数据配置问题
         *
         * @throws IOException 抛出数据异常类
         */
        protected void checkConfig() throws IOException {
            if (heardKey == null || heardList.length == 0) {
                throw new IOException("列名数组不能为空或者为NULL");
            }
    
            if (fontSize < 0 || rowHeight < 0 || columWidth < 0) {
                throw new IOException("字体、宽度或者高度不能为负值");
            }
    
            if (Strings.isNullOrEmpty(sheetName)) {
                throw new IOException("工作表表名不能为NULL");
            }
        }
    }

     service :

     @Override
        public void queryProjectInfoBySchemeId(HttpServletResponse response, HttpServletRequest request,
                                                       String schemeId, String pushDate) throws IOException {
            List<Map> maps = pushMonitorDao.queryProjectInfoBySchemeId(schemeId, pushDate);
            if(maps!=null && maps.size()>0){
                 String companyName = pushMonitorDao.queryCompanyNameBySchemeId(schemeId);
                 String sheetTitle = companyName;
                 String [] title = new String[]{"城市","项目名字","合同","实际"};        //设置表格表头字段
                String [] properties = new String[]{"city","projectName","ddNum","sjNum"};  // 查询对应的字段
                ExcelExportUtil excelExport2 = new ExcelExportUtil();
                excelExport2.setData(maps);
                excelExport2.setHeardKey(properties);
                excelExport2.setFontSize(14);
                excelExport2.setSheetName(sheetTitle);
                excelExport2.setTitle(sheetTitle);
                excelExport2.setHeardList(title);
                excelExport2.exportExport(request, response);
             }
        }

     由于上面的代码不够灵活,下面加以改进:

    ExcelExportUtil:
    package com.zhl.push.Utils;
    
    import org.apache.poi.hssf.util.HSSFColor;
    import org.apache.poi.ss.usermodel.*;
    
    import javax.servlet.http.HttpServletResponse;
    import java.io.IOException;
    import java.io.OutputStream;
    import java.util.List;
    import java.util.Map;
    
    public class ExcelExportUtil {
    
        //excel表对象
        private Workbook workbook;
        //工作表对象
        private Sheet sheet;
        //标题
        private String title;
        //sheet各个列的表头
        private String[] headList;
        //各个列的元素key值
        private String[] headKey;
        //sheet需要填充的数据信息
        private List<Map> data;
        //工作表名称
    //    private String sheetName = "sheet1";
        //工作表列宽
        private Integer columnWidth=20;
        //工作表行高
        private Integer rowHeight=10;
        //字体大小
        private int fontSize = 14;
    
        public int getFontSize() {
            return fontSize;
        }
    
        public void setFontSize(int fontSize) {
            this.fontSize = fontSize;
        }
    
        public Integer getColumnWidth() {
            return columnWidth;
        }
    
        public void setColumnWidth(Integer columnWidth) {
            this.columnWidth = columnWidth;
        }
    
        public Integer getRowHeight() {
            return rowHeight;
        }
    
        public void setRowHeight(Integer rowHeight) {
            this.rowHeight = rowHeight;
        }
    
        public Workbook getWorkbook() {
            return workbook;
        }
    
        public void setWorkbook(Workbook workbook) {
            this.workbook = workbook;
        }
    
        public Sheet getSheet() {
            return sheet;
        }
    
        public void setSheet(Sheet sheet) {
            this.sheet = sheet;
        }
    
        public String[] getHeadKey() {
            return headKey;
        }
    
        public void setHeadKey(String[] headKey) {
            this.headKey = headKey;
        }
    
        public String getTitle() {
            return title;
        }
    
        public void setTitle(String title) {
            this.title = title;
        }
    
        public String[] getHeadList() {
            return headList;
        }
    
        public void setHeadList(String[] headList) {
            this.headList = headList;
        }
    
        public List<Map> getData() {
            return data;
        }
    
        public void setData(List<Map> data) {
            this.data = data;
        }
    
    
    
    
    
        /**
         * @return *
         * @Author
         * @Description //TODO 插入数据到表格(body)
         * @Date 2019/7/26 17:28
         * @Param startRow: 开始插入数据的行
         */
        public void writeMainData(Integer startRow) throws IOException {
            //设置每格数据的样式 (字体红色)
            CellStyle fontRed = ExcelStyleUtilFor2003.getFontStyle(this.workbook, this.fontSize, HSSFColor.RED.index);
            //设置每格数据的样式2(字体蓝色)
            CellStyle fontBlue = ExcelStyleUtilFor2003.getFontStyle(this.workbook, this.fontSize, HSSFColor.BLUE.index);
            //设置body样式
            CellStyle bodyStyle = ExcelStyleUtilFor2003.getBodyStyle(this.workbook, this.fontSize);
    
            //开始写入实体数据信息
            if (data.size() > 0 && null != data.get(0)) {
                for (int i = 0; i < data.size(); i++) {
                    Row row = this.sheet.createRow(startRow);
                    Map map = data.get(i);
                    map.put("index",i);
                    map.put("des","无");
                    for (int j = 0; j < headKey.length; j++) {
                        Cell cell = row.createCell(j);
                        Object value = map.get(headKey[j]);
                            if (null == value) {
                                String valueN = "";
                                cell.setCellValue(valueN);
                            } else if (value instanceof Integer) {
                                Integer valueInt = Integer.valueOf(value.toString());
                                cell.setCellValue(valueInt);
                            } else if (value instanceof String) {
                                String valueStr = String.valueOf(value);
                                cell.setCellValue(valueStr);
                            }
                        }
                    }
                    startRow++;
                }
            }
    
    
        }
    
    
        /**
         * @return * @param null
         * @Author
         * @Description //TODO 添加表格标题
         * @Date 2019/7/26 17:58
         * @Param
         */
        public void writeTitle() throws IOException {
            checkConfig();
            //设置默认行宽
            this.sheet.setDefaultColumnWidth(20);
            //在第0行创建rows  (表标题)
            Row title = this.sheet.createRow(0);
            title.setHeightInPoints(this.rowHeight);//行高
            Cell cell = title.createCell(0);
            cell.setCellValue(this.title);
            CellStyle cellStyle = ExcelStyleUtilFor2003.getTitleStyle(this.workbook,true,16);
            cell.setCellStyle(cellStyle);
            ExcelStyleUtilFor2003.mergeCell(sheet,0,0,0, (this.headList.length - 1));
        }
    
    
        /**
         * @Author
         * @Description //TODO 添加表头
         * @Date 2019/7/26 15:41
         * @Param headRowNum: 添加表头所在行数
         * @return  *
         */
    
        public void writeTableHead(String[] head, CellStyle cellStyle,Integer headRowNum) {
            Row row = this.sheet.createRow(headRowNum);
            if (head.length > 0) {
                for (int i = 0; i < head.length; i++) {
                    Cell cell = row.createCell(i);
                    cell.setCellValue(head[i]);
                    cell.setCellStyle(cellStyle);
                }
            }
        }
    
    
        /**
         * 检查数据配置问题
         *
         * @throws IOException 抛出数据异常类
         */
        protected void checkConfig() throws IOException {
            if (headKey == null || headList.length == 0) {
                throw new IOException("列名数组不能为空或者为NULL");
            }
            if (fontSize < 0) {
                throw new IOException("字体不能为负值");
            }
        }
    
        /**
         * @Author
         * @Description //TODO 写入拼接好的数据,不需要通过表头key值来对应
         * @Date 2019/7/27 11:01
         * @Param
         * @return  * @param null
         */
        public void writeMainData(List<List<String>> datas,Integer startRow){
            if(datas.size()>0){
                for(List<String> data : datas){
                    Row row = this.sheet.createRow(startRow);
                    for(int i =0; i<data.size(); i++){
                        Cell cell = row.createCell(i);
                        cell.setCellValue(data.get(i));
                        CellStyle cellStyle = ExcelStyleUtilFor2003.setCellBorder(this.workbook);
                        cell.setCellStyle(cellStyle);
                    }
                    startRow++;
                }
            }
        }
    
    
    
        public static void setResponseInfo(HttpServletResponse response, Workbook wb) throws IOException {
            //导出数据
            try {
                //设置Http响应头告诉浏览器下载这个附件
                response.setHeader("Content-Disposition", "attachment;Filename=" + System.currentTimeMillis() + ".xls");
                OutputStream outputStream = response.getOutputStream();
                wb.write(outputStream);
                outputStream.close();
            } catch (Exception ex) {
                ex.printStackTrace();
                throw new IOException("导出Excel出现严重异常,异常信息:" + ex.getMessage());
            }
        }
    
    }

    我们把样式单独提取成一个工具类:

    package com.zhl.push.Utils;
    
    import org.apache.poi.hssf.usermodel.HSSFCellStyle;
    import org.apache.poi.hssf.util.HSSFColor;
    import org.apache.poi.ss.usermodel.*;
    import org.apache.poi.ss.util.CellRangeAddress;
    
    /**
     * @Author
     * @ClassName ExcelStyleUtilFor2003
     * @Description TODO
     * @Date 2019/7/26 14:16
     * @Version 1.0
     */
    public class ExcelStyleUtilFor2003 {
    
    
        /**
         * @return * @param null
         * @Author
         * @Description //TODO 样式居中
         * @Date 2019/7/26 14:51
         * @Param
         */
        public static void center(CellStyle cellStyle) {
            cellStyle.setAlignment(HorizontalAlignment.CENTER);//水平居中
            cellStyle.setVerticalAlignment(VerticalAlignment.CENTER);//垂直居中
        }
    
        /**
         * @return * @param null
         * @Author
         * @Description //TODO 单元格合并
         * @Date 2019/7/26 14:54
         * @Param wbSheet :工作表对象
         * firstRow :合并的开始行
         * lastRow:合并的结束行
         * firstCol: 合并的开始列
         * lastColL: 合并的结束列
         */
        public static void mergeCell(Sheet wbSheet, int firstRow, int lastRow, int firstCol, int lastCol) {
            wbSheet.addMergedRegion(new CellRangeAddress(firstRow, lastRow, firstCol, lastCol));
        }
    
    
        /**
         * @return *
         * @Author
         * @Description //TODO 标题样式 :加粗,垂直居中
         * @Date 2019/7/26 14:21
         * @Param
         */
        public static CellStyle getTitleStyle(Workbook wb, Boolean isBold, int FontISize) {
            // 标题样式(加粗,垂直居中)
            CellStyle cellStyle = wb.createCellStyle();
            center(cellStyle);
            Font font = wb.createFont();
            font.setBold(isBold);   //加粗
            font.setFontHeightInPoints((short) FontISize);  //设置标题字体大小
            cellStyle.setFont(font);
            return cellStyle;
        }
    
        /**
         * @return *
         * @Author
         * @Description //TODO 表头样式
         * @Date 2019/7/26 14:30
         * @Param
         */
        public static CellStyle getHeadStyle(Workbook wb, int fontSize) {
            CellStyle cellStyle = wb.createCellStyle();
            cellStyle.setFillForegroundColor(HSSFColor.AQUA.index);//设置表头的背景颜色
            cellStyle.setFillPattern(FillPatternType.SOLID_FOREGROUND);
            cellStyle.setFillBackgroundColor(HSSFColor.AQUA.index); //设置表头的背景颜色
            center(cellStyle);
            //设置字体
            Font font = setFont(wb, fontSize);
            cellStyle.setFont(font);
            return cellStyle;
        }
    
        /**
         * @return * @param null
         * @Author
         * @Description //TODO body通用样式: 居中,设置字体大小
         * @Date 2019/7/26 15:11
         * @Param
         */
        public static CellStyle getBodyStyle(Workbook wb, int fontSize) {
            CellStyle cellStyle = wb.createCellStyle();
            //设置单元格样式
            center(cellStyle);
            Font font = setFont(wb, fontSize);
            cellStyle.setFont(font);
            return cellStyle;
        }
    
        /**
         * @return * @param null
         * @Author
         * @Description //TODO 设置单元格字体居中、并设置字体颜色
         * @Date 2019/7/26 15:26
         * @Param
         */
        public static CellStyle getFontStyle(Workbook wb, int fontSize, short color) {
            CellStyle cellStyle = wb.createCellStyle();
            Font font = setFont(wb, fontSize, color);
            center(cellStyle);
            cellStyle.setFont(font);
            return cellStyle;
        }
    
    
        /**
         * @return * @param null
         * @Author
         * @Description //TODO 设置单元格字体
         * @Date 2019/7/26 15:16
         * @Param
         */
        public static Font setFont(Workbook wb, int fontSize, short color) {
            //设置字体
            Font font = wb.createFont();
            font.setColor(color);
            font.setFontHeightInPoints((short) fontSize);
            return font;
        }
    
        public static Font setFont(Workbook wb, int fontSize) {
            //设置字体
            Font font = wb.createFont();
            font.setFontHeightInPoints((short) fontSize);
            return font;
        }
    
        /**
         * @Author
         * @Description //TODO 设置cell边框
         * @Date 2019/7/27 16:16
         * @Param
         * @return  * @param null
         */
        public static CellStyle setCellBorder(Workbook workbook){
            CellStyle cellStyle = workbook.createCellStyle();
            //设置了边框属性
            cellStyle.setBorderBottom(BorderStyle.THIN); //下边框
            cellStyle.setBorderLeft(BorderStyle.THIN);//左边框
            cellStyle.setBorderTop(BorderStyle.THIN);//上边框
            cellStyle.setBorderRight(BorderStyle.THIN);//右边框
            //设置边框颜色黑色
            cellStyle.setTopBorderColor(HSSFColor.BLACK.index);
            cellStyle.setBottomBorderColor(HSSFColor.BLACK.index);
            cellStyle.setLeftBorderColor(HSSFColor.BLACK.index);
            cellStyle.setRightBorderColor(IndexedColors.BLACK.index); 
    return cellStyle;
    }
    }

     =======================================================

    如果需要使用模板来导出excel可以使用jxls:

    官网:http://jxls.sourceforge.net/

    可以参考博客:  https://www.cnblogs.com/foxlee1024/p/7616987.html

    https://blog.csdn.net/sinat_15769727/article/details/78898894

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  • 原文地址:https://www.cnblogs.com/dw3306/p/9522880.html
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