通用型——excel导出/下载工具类

 工具类代码：

package com.eden.smarthome.common.util;

import java.io.IOException;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.List;

import javax.servlet.http.HttpServletResponse;

import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFCellStyle;
import org.apache.poi.hssf.usermodel.HSSFFont;
import org.apache.poi.hssf.usermodel.HSSFRichTextString;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.hssf.util.HSSFColor;
import org.apache.poi.ss.util.CellRangeAddress;

/**
 * @FileName ExcelUtil.java
 * @Description:
 *
 * @Date 2019年1月17日 下午1:31:06
 * @author Eden
 * @version 1.0
 */
public class ExcelUtil {
    //显示的导出表的标题
    private String title;
    //导出表的列名
    private String[] rowName ;
    
    private List<Object[]>  dataList = new ArrayList<Object[]>();
    
    HttpServletResponse  response;
    
    //构造方法，传入要导出的数据
    public ExcelUtil(String title,String[] rowName,List<Object[]>  dataList){
        this.dataList = dataList;
        this.rowName = rowName;
        this.title = title;
    }
            
    /*
     * 导出数据
     * */
    public void export(HttpServletResponse response) throws Exception{
        try{
            HSSFWorkbook workbook = new HSSFWorkbook();                        // 创建工作簿对象
            HSSFSheet sheet = workbook.createSheet(title);                     // 创建工作表
            
            // 产生表格标题行
            HSSFRow rowm = sheet.createRow(0);
            HSSFCell cellTiltle = rowm.createCell(0);
            
            //sheet样式定义【getColumnTopStyle()/getStyle()均为自定义方法 - 在下面  - 可扩展】
            HSSFCellStyle columnTopStyle = this.getColumnTopStyle(workbook);//获取列头样式对象
            HSSFCellStyle style = this.getStyle(workbook);                    //单元格样式对象
            
            sheet.addMergedRegion(new CellRangeAddress(0, 1, 0, (rowName.length-1)));  
            cellTiltle.setCellStyle(columnTopStyle);
            cellTiltle.setCellValue(title);
            
            // 定义所需列数
            int columnNum = rowName.length;
            HSSFRow rowRowName = sheet.createRow(2);                // 在索引2的位置创建行(最顶端的行开始的第二行)
            
            // 将列头设置到sheet的单元格中
            for(int n=0;n<columnNum;n++){
                HSSFCell  cellRowName = rowRowName.createCell(n);                //创建列头对应个数的单元格
                cellRowName.setCellType(HSSFCell.CELL_TYPE_STRING);                //设置列头单元格的数据类型
                HSSFRichTextString text = new HSSFRichTextString(rowName[n]);
                cellRowName.setCellValue(text);                                    //设置列头单元格的值
                cellRowName.setCellStyle(columnTopStyle);                        //设置列头单元格样式
            }
            
            //将查询出的数据设置到sheet对应的单元格中
            for(int i=0;i<dataList.size();i++){
                
                Object[] obj = dataList.get(i);//遍历每个对象
                HSSFRow row = sheet.createRow(i+3);//创建所需的行数
                
                for(int j=0; j<obj.length; j++){
                    HSSFCell  cell = null;   //设置单元格的数据类型
                    if(j == 0){
                        cell = row.createCell(j,HSSFCell.CELL_TYPE_NUMERIC);
                        cell.setCellValue(i+1);    
                    }else{
                        cell = row.createCell(j,HSSFCell.CELL_TYPE_STRING);
                        if(!"".equals(obj[j]) && obj[j] != null){
                            cell.setCellValue(obj[j].toString());                        //设置单元格的值
                        }
                    }
                    cell.setCellStyle(style);                                    //设置单元格样式
                }
            }
            //让列宽随着导出的列长自动适应
            for (int colNum = 0; colNum < columnNum; colNum++) {
                int columnWidth = sheet.getColumnWidth(colNum) / 256;
                for (int rowNum = 0; rowNum < sheet.getLastRowNum(); rowNum++) {
                    HSSFRow currentRow;
                    //当前行未被使用过
                    if (sheet.getRow(rowNum) == null) {
                        currentRow = sheet.createRow(rowNum);
                    } else {
                        currentRow = sheet.getRow(rowNum);
                    }
                    if (currentRow.getCell(colNum) != null) {
                        HSSFCell currentCell = currentRow.getCell(colNum);
                        if (currentCell.getCellType() == HSSFCell.CELL_TYPE_STRING) {
                            int length = currentCell.getStringCellValue().getBytes().length;
                            if (columnWidth < length) {
                                columnWidth = length;
                            }
                        }
                    }
                }
                if(colNum == 0){
                    sheet.setColumnWidth(colNum, (columnWidth-2) * 256);
                }else{
                    sheet.setColumnWidth(colNum, (columnWidth+4) * 256);
                }
            }
            
            if(workbook !=null){
                try{
                    String fileName = title + String.valueOf(System.currentTimeMillis()).substring(4, 13) + ".xls";
                    String headStr = "attachment; filename=\"" + fileName + "\"";
                    response.setContentType("APPLICATION/OCTET-STREAM");
                    response.setHeader("Content-Disposition", headStr);
                    OutputStream out = response.getOutputStream();
                    workbook.write(out);
                }catch (IOException e){
                    e.printStackTrace();
                }
            }
        }catch(Exception e){
            e.printStackTrace();
        }
        
    }
    
    /* 
     * 列头单元格样式
     */    
      public HSSFCellStyle getColumnTopStyle(HSSFWorkbook workbook) {
          
            // 设置字体
          HSSFFont font = workbook.createFont();
          //设置字体大小
          font.setFontHeightInPoints((short)11);
          //字体加粗
          font.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
          //设置字体名字 
          font.setFontName("Courier New");
          //设置样式; 
          HSSFCellStyle style = workbook.createCellStyle();
          //设置底边框; 
          style.setBorderBottom(HSSFCellStyle.BORDER_THIN);
          //设置底边框颜色;  
          style.setBottomBorderColor(HSSFColor.BLACK.index);
          //设置左边框;   
          style.setBorderLeft(HSSFCellStyle.BORDER_THIN);
          //设置左边框颜色; 
          style.setLeftBorderColor(HSSFColor.BLACK.index);
          //设置右边框; 
          style.setBorderRight(HSSFCellStyle.BORDER_THIN);
          //设置右边框颜色; 
          style.setRightBorderColor(HSSFColor.BLACK.index);
          //设置顶边框; 
          style.setBorderTop(HSSFCellStyle.BORDER_THIN);
          //设置顶边框颜色;  
          style.setTopBorderColor(HSSFColor.BLACK.index);
          //在样式用应用设置的字体;  
          style.setFont(font);
          //设置自动换行; 
          style.setWrapText(false);
          //设置水平对齐的样式为居中对齐;  
          style.setAlignment(HSSFCellStyle.ALIGN_CENTER);
          //设置垂直对齐的样式为居中对齐; 
          style.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);
          
          return style;
          
      }
      
      /*  
     * 列数据信息单元格样式
     */  
      public HSSFCellStyle getStyle(HSSFWorkbook workbook) {
            // 设置字体
            HSSFFont font = workbook.createFont();
            //设置字体大小
            //font.setFontHeightInPoints((short)10);
            //字体加粗
            //font.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
            //设置字体名字 
            font.setFontName("Courier New");
            //设置样式; 
            HSSFCellStyle style = workbook.createCellStyle();
            //设置底边框; 
            style.setBorderBottom(HSSFCellStyle.BORDER_THIN);
            //设置底边框颜色;  
            style.setBottomBorderColor(HSSFColor.BLACK.index);
            //设置左边框;   
            style.setBorderLeft(HSSFCellStyle.BORDER_THIN);
            //设置左边框颜色; 
            style.setLeftBorderColor(HSSFColor.BLACK.index);
            //设置右边框; 
            style.setBorderRight(HSSFCellStyle.BORDER_THIN);
            //设置右边框颜色; 
            style.setRightBorderColor(HSSFColor.BLACK.index);
            //设置顶边框; 
            style.setBorderTop(HSSFCellStyle.BORDER_THIN);
            //设置顶边框颜色;  
            style.setTopBorderColor(HSSFColor.BLACK.index);
            //在样式用应用设置的字体;  
            style.setFont(font);
            //设置自动换行; 
            style.setWrapText(false);
            //设置水平对齐的样式为居中对齐;  
            style.setAlignment(HSSFCellStyle.ALIGN_CENTER);
            //设置垂直对齐的样式为居中对齐; 
            style.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);
           
            return style;
      
      }
}

调用代码示例：

String title = Message.getString("manifestIExportTitle");
String[] rowsName = new String[]{"序号","货物运输批次号","提运单号","状态","录入人","录入时间"};
List<Object[]>  dataList = new ArrayList<Object[]>();
Object[] objs = null;
for (int i = 0; i < manifestIMainList.size(); i++) {
    ManifestIMain man = manifestIMainList.get(i);
    objs = new Object[rowsName.length];
    objs[0] = i;
    objs[1] = man.getTranNo();
   objs[2] = man.getBillNo();
   objs[3] = man.getStatusFlagCnName();
   objs[4] = man.getLoginName();
   SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
   String date = df.format(man.getModiDate());
   objs[5] = date;
   dataList.add(objs);
}
ExportExcel ex = new ExportExcel(title, rowsName, dataList);
ex.export();