web开发使用poi 导出excel

1： 添加jar依赖

<dependency>
      <groupId>org.apache.poi</groupId>
      <artifactId>poi-ooxml</artifactId>
   <version>3.9</version>
</dependency>

2：编写工具类

import java.io.IOException;
import java.io.OutputStream;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.sql.Date;
import java.text.SimpleDateFormat;
import java.util.Collection;
import java.util.Iterator;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.apache.commons.lang.ObjectUtils.Null;
import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFCellStyle;
import org.apache.poi.hssf.usermodel.HSSFClientAnchor;
import org.apache.poi.hssf.usermodel.HSSFComment;
import org.apache.poi.hssf.usermodel.HSSFFont;
import org.apache.poi.hssf.usermodel.HSSFPatriarch;
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;

public class ExportExcel<T> {

   public void exportExcel(Collection<T> dataset, OutputStream out) {
       exportExcel("测试POI导出EXCEL文档", null, dataset, out, "yyyy-MM-dd");
   }

   public void exportExcel(String[] headers, Collection<T> dataset,
           OutputStream out) {
       exportExcel("测试POI导出EXCEL文档", headers, dataset, out, "yyyy-MM-dd");
   }
   public HSSFWorkbook exportExcel(String[] headers, Collection<T> dataset) {
     return exportExcel("测试POI导出EXCEL文档", headers, dataset, "yyyy-MM-dd");
   }

   public void exportExcel(String[] headers, Collection<T> dataset,
           OutputStream out, String pattern) {
       exportExcel("测试POI导出EXCEL文档", headers, dataset, out, pattern);
   }

   /**
    * 这是一个通用的方法，利用了JAVA的反射机制，可以将放置在JAVA集合中并且符号一定条件的数据以EXCEL 的形式输出到指定IO设备上
    * 
    * @param title
    *            表格标题名
    * @param headers
    *            表格属性列名数组
    * @param dataset
    *            需要显示的数据集合,集合中一定要放置符合javabean风格的类的对象。此方法支持的
    *            javabean属性的数据类型有基本数据类型及String,Date,byte[](图片数据)
    * @param out
    *            与输出设备关联的流对象，可以将EXCEL文档导出到本地文件或者网络中
    * @param pattern
    *            如果有时间数据，设定输出格式。默认为"yyy-MM-dd"
    */
   @SuppressWarnings("unchecked")
   public void exportExcel(String title, String[] headers,
           Collection<T> dataset, OutputStream out, String pattern) {
       // 声明一个工作薄
       HSSFWorkbook workbook = new HSSFWorkbook();
       // 生成一个表格
       HSSFSheet sheet = workbook.createSheet(title);
       // 设置表格默认列宽度为15个字节
       sheet.setDefaultColumnWidth((short) 15);
       // 生成一个样式
       HSSFCellStyle style = workbook.createCellStyle();
       // 设置这些样式
       style.setFillForegroundColor(HSSFColor.SKY_BLUE.index);
       style.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND);
       style.setBorderBottom(HSSFCellStyle.BORDER_THIN);
       style.setBorderLeft(HSSFCellStyle.BORDER_THIN);
       style.setBorderRight(HSSFCellStyle.BORDER_THIN);
       style.setBorderTop(HSSFCellStyle.BORDER_THIN);
       style.setAlignment(HSSFCellStyle.ALIGN_CENTER);
       // 生成一个字体
       HSSFFont font = workbook.createFont();
       font.setColor(HSSFColor.VIOLET.index);
       font.setFontHeightInPoints((short) 12);
       font.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
       // 把字体应用到当前的样式
       style.setFont(font);
       // 生成并设置另一个样式
       HSSFCellStyle style2 = workbook.createCellStyle();
       style2.setFillForegroundColor(HSSFColor.LIGHT_YELLOW.index);
       style2.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND);
       style2.setBorderBottom(HSSFCellStyle.BORDER_THIN);
       style2.setBorderLeft(HSSFCellStyle.BORDER_THIN);
       style2.setBorderRight(HSSFCellStyle.BORDER_THIN);
       style2.setBorderTop(HSSFCellStyle.BORDER_THIN);
       style2.setAlignment(HSSFCellStyle.ALIGN_CENTER);
       style2.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);
       // 生成另一个字体
       HSSFFont font2 = workbook.createFont();
       font2.setBoldweight(HSSFFont.BOLDWEIGHT_NORMAL);
       // 把字体应用到当前的样式
       style2.setFont(font2);

       // 声明一个画图的顶级管理器
       HSSFPatriarch patriarch = sheet.createDrawingPatriarch();
       // 定义注释的大小和位置,详见文档
       HSSFComment comment = patriarch.createComment(new HSSFClientAnchor(0,
               0, 0, 0, (short) 4, 2, (short) 6, 5));
       // 设置注释内容
       comment.setString(new HSSFRichTextString("可以在POI中添加注释！"));
       // 设置注释作者，当鼠标移动到单元格上是可以在状态栏中看到该内容.
       comment.setAuthor("leno");

       // 产生表格标题行
       HSSFRow row = sheet.createRow(0);
       for (short i = 0; i < headers.length; i++) {
           HSSFCell cell = row.createCell(i);
           cell.setCellStyle(style);
           HSSFRichTextString text = new HSSFRichTextString(headers[i]);
           cell.setCellValue(text);
       }

       // 遍历集合数据，产生数据行
       Iterator<T> it = dataset.iterator();
       int index = 0;
       while (it.hasNext()) {
           index++;
           row = sheet.createRow(index);
           T t = (T) it.next();
           // 利用反射，根据javabean属性的先后顺序，动态调用getXxx()方法得到属性值
           Field[] fields = t.getClass().getDeclaredFields();
           for (short i = 0; i < fields.length; i++) {
               HSSFCell cell = row.createCell(i);
               cell.setCellStyle(style2);
               Field field = fields[i];
               String fieldName = field.getName();
               String getMethodName = "get"
                       + fieldName.substring(0, 1).toUpperCase()
                       + fieldName.substring(1);
               try {
                   Class tCls = t.getClass();
                   Method getMethod = tCls.getMethod(getMethodName,
                           new Class[] {});
                   Object value = getMethod.invoke(t, new Object[] {});
                   // 判断值的类型后进行强制类型转换
                   String textValue = null;
                   // if (value instanceof Integer) {
                   // int intValue = (Integer) value;
                   // cell.setCellValue(intValue);
                   // } else if (value instanceof Float) {
                   // float fValue = (Float) value;
                   // textValue = new HSSFRichTextString(
                   // String.valueOf(fValue));
                   // cell.setCellValue(textValue);
                   // } else if (value instanceof Double) {
                   // double dValue = (Double) value;
                   // textValue = new HSSFRichTextString(
                   // String.valueOf(dValue));
                   // cell.setCellValue(textValue);
                   // } else if (value instanceof Long) {
                   // long longValue = (Long) value;
                   // cell.setCellValue(longValue);
                   // }
                   if (value instanceof Boolean) {
                       boolean bValue = (Boolean) value;
                       textValue = "男";
                       if (!bValue) {
                           textValue = "女";
                       }
                   } else if (value instanceof Date) {
                       Date date = (Date) value;
                       SimpleDateFormat sdf = new SimpleDateFormat(pattern);
                       textValue = sdf.format(date);
                   } else if (value instanceof byte[]) {
                       // 有图片时，设置行高为60px;
                       row.setHeightInPoints(60);
                       // 设置图片所在列宽度为80px,注意这里单位的一个换算
                       sheet.setColumnWidth(i, (short) (35.7 * 80));
                       // sheet.autoSizeColumn(i);
                       byte[] bsValue = (byte[]) value;
                       HSSFClientAnchor anchor = new HSSFClientAnchor(0, 0,
                               1023, 255, (short) 6, index, (short) 6, index);
                       anchor.setAnchorType(2);
                       patriarch.createPicture(anchor, workbook.addPicture(
                               bsValue, HSSFWorkbook.PICTURE_TYPE_JPEG));
                   } else {
                       // 其它数据类型都当作字符串简单处理
                       textValue = value.toString();
                   }
                   // 如果不是图片数据，就利用正则表达式判断textValue是否全部由数字组成
                   if (textValue != null) {
                       Pattern p = Pattern.compile("^//d+(//.//d+)?$");
                       Matcher matcher = p.matcher(textValue);
                       if (matcher.matches()) {
                           // 是数字当作double处理
                           cell.setCellValue(Double.parseDouble(textValue));
                       } else {
                           HSSFRichTextString richString = new HSSFRichTextString(
                                   textValue);
                           HSSFFont font3 = workbook.createFont();
                           font3.setColor(HSSFColor.BLUE.index);
                           richString.applyFont(font3);
                           cell.setCellValue(richString);
                       }
                   }
               } catch (SecurityException e) {
                   // TODO Auto-generated catch block
                   e.printStackTrace();
               } catch (NoSuchMethodException e) {
                   // TODO Auto-generated catch block
                   e.printStackTrace();
               } catch (IllegalArgumentException e) {
                   // TODO Auto-generated catch block
                   e.printStackTrace();
               } catch (IllegalAccessException e) {
                   // TODO Auto-generated catch block
                   e.printStackTrace();
               } catch (InvocationTargetException e) {
                   // TODO Auto-generated catch block
                   e.printStackTrace();
               } finally {
                   // 清理资源
               }
           }

       }
       try {
           workbook.write(out);
       } catch (IOException e) {
           // TODO Auto-generated catch block
           e.printStackTrace();
       }

   }
   
   
   public HSSFWorkbook exportExcel(String title, String[] headers,
           Collection<T> dataset, String pattern) {
       // 声明一个工作薄
       HSSFWorkbook workbook = new HSSFWorkbook();
       // 生成一个表格
       HSSFSheet sheet = workbook.createSheet(title);
       // 设置表格默认列宽度为15个字节
       sheet.setDefaultColumnWidth((short) 15);
       // 生成一个样式
       HSSFCellStyle style = workbook.createCellStyle();
       // 设置这些样式
       style.setFillForegroundColor(HSSFColor.SKY_BLUE.index);
       style.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND);
       style.setBorderBottom(HSSFCellStyle.BORDER_THIN);
       style.setBorderLeft(HSSFCellStyle.BORDER_THIN);
       style.setBorderRight(HSSFCellStyle.BORDER_THIN);
       style.setBorderTop(HSSFCellStyle.BORDER_THIN);
       style.setAlignment(HSSFCellStyle.ALIGN_CENTER);
       // 生成一个字体
       HSSFFont font = workbook.createFont();
       font.setColor(HSSFColor.VIOLET.index);
       font.setFontHeightInPoints((short) 12);
       font.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
       // 把字体应用到当前的样式
       style.setFont(font);
       // 生成并设置另一个样式
       HSSFCellStyle style2 = workbook.createCellStyle();
       style2.setFillForegroundColor(HSSFColor.LIGHT_YELLOW.index);
       style2.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND);
       style2.setBorderBottom(HSSFCellStyle.BORDER_THIN);
       style2.setBorderLeft(HSSFCellStyle.BORDER_THIN);
       style2.setBorderRight(HSSFCellStyle.BORDER_THIN);
       style2.setBorderTop(HSSFCellStyle.BORDER_THIN);
       style2.setAlignment(HSSFCellStyle.ALIGN_LEFT);
       style2.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);
       // 生成另一个字体
       HSSFFont font2 = workbook.createFont();
       font2.setBoldweight(HSSFFont.BOLDWEIGHT_NORMAL);
       // 把字体应用到当前的样式
       style2.setFont(font2);

       // 声明一个画图的顶级管理器
       HSSFPatriarch patriarch = sheet.createDrawingPatriarch();
       // 定义注释的大小和位置,详见文档
       HSSFComment comment = patriarch.createComment(new HSSFClientAnchor(0,
               0, 0, 0, (short) 4, 2, (short) 6, 5));
       // 设置注释内容
       comment.setString(new HSSFRichTextString("可以在POI中添加注释！"));
       // 设置注释作者，当鼠标移动到单元格上是可以在状态栏中看到该内容.
       comment.setAuthor("leno");

       // 产生表格标题行
       HSSFRow row = sheet.createRow(0);
       for (short i = 0; i < headers.length; i++) {
           HSSFCell cell = row.createCell(i);
           cell.setCellStyle(style);
           HSSFRichTextString text = new HSSFRichTextString(headers[i]);
           cell.setCellValue(text);
       }

       // 遍历集合数据，产生数据行
       Iterator<T> it = dataset.iterator();
       int index = 0;
       while (it.hasNext()) {
           index++;
           row = sheet.createRow(index);
           T t = (T) it.next();
           // 利用反射，根据javabean属性的先后顺序，动态调用getXxx()方法得到属性值
           Field[] fields = t.getClass().getDeclaredFields();
           for (short i = 0; i < fields.length; i++) {
               HSSFCell cell = row.createCell(i);
               cell.setCellStyle(style2);
               Field field = fields[i];
               String fieldName = field.getName();
               String getMethodName = "get"
                       + fieldName.substring(0, 1).toUpperCase()
                       + fieldName.substring(1);
               try {
                   Class tCls = t.getClass();
                   Method getMethod = tCls.getMethod(getMethodName,
                           new Class[] {});
                   Object value = getMethod.invoke(t, new Object[] {});
                   // 判断值的类型后进行强制类型转换
                   String textValue = null;    
                   if (value==null) {
                       textValue = null;
                   }else if (value instanceof Boolean) {
                       boolean bValue = (Boolean) value;
                       textValue = "男";
                       if (!bValue) {
                           textValue = "女";
                       }
                   } else if (value instanceof Date) {
                       Date date = (Date) value;
                       SimpleDateFormat sdf = new SimpleDateFormat(pattern);
                       textValue = sdf.format(date);
                   } else if (value instanceof byte[]) {
                       // 有图片时，设置行高为60px;
                       row.setHeightInPoints(60);
                       // 设置图片所在列宽度为80px,注意这里单位的一个换算
                       sheet.setColumnWidth(i, (short) (35.7 * 80));
                       // sheet.autoSizeColumn(i);
                       byte[] bsValue = (byte[]) value;
                       HSSFClientAnchor anchor = new HSSFClientAnchor(0, 0,
                               1023, 255, (short) 6, index, (short) 6, index);
                       anchor.setAnchorType(2);
                       patriarch.createPicture(anchor, workbook.addPicture(
                               bsValue, HSSFWorkbook.PICTURE_TYPE_JPEG));
                   } else {
                       // 其它数据类型都当作字符串简单处理
                       textValue = value.toString();
                   }
                   // 如果不是图片数据，就利用正则表达式判断textValue是否全部由数字组成
                   if (textValue != null) {
                       Pattern p = Pattern.compile("^//d+(//.//d+)?$");
                       Matcher matcher = p.matcher(textValue);
                       if (matcher.matches()) {
                           // 是数字当作double处理
                           cell.setCellValue(Double.parseDouble(textValue));
                       } else {
                           HSSFRichTextString richString = new HSSFRichTextString(
                                   textValue);
                           HSSFFont font3 = workbook.createFont();
                           font3.setColor(HSSFColor.BLUE.index);
                           richString.applyFont(font3);
                           cell.setCellValue(richString);
                       }
                   }
               } catch (SecurityException e) {
                   // TODO Auto-generated catch block
                   e.printStackTrace();
               } catch (NoSuchMethodException e) {
                   // TODO Auto-generated catch block
                   e.printStackTrace();
               } catch (IllegalArgumentException e) {
                   // TODO Auto-generated catch block
                   e.printStackTrace();
               } catch (IllegalAccessException e) {
                   // TODO Auto-generated catch block
                   e.printStackTrace();
               } catch (InvocationTargetException e) {
                   // TODO Auto-generated catch block
                   e.printStackTrace();
               } finally {
                   // 清理资源
               }
           }
       }
       return workbook;        
   }   
}

3：在web controller 里获得数据源后直接调用工具类（注意：在前台点击事件导出表格的时候， 点击事件要使用 location.href="/bmw/ex?city="+id; 发送请求，不然不会出现下载界面）

 @Get("/ex")
   public void getexcle2(HttpServletRequest request,
           HttpServletResponse response, @Param("city") int city) {
       ExportExcel<BmwEntity> ex = new ExportExcel<BmwEntity>();
       String[] headers = { "id", "车源型号", "卖家名称", "电话", "地址","城市" };
       //这里获得数据源
               List<BmwEntity> dataset = bmwService.getData(city);
       HSSFWorkbook book = ex.exportExcel(headers, dataset);
       response.setContentType("application/vnd.ms-excel");
       response.setHeader("Content-disposition",
               "attachment;filename=bmw.xls");
       OutputStream ouputStream;
       try {
           ouputStream = response.getOutputStream();
           book.write(ouputStream);
           ouputStream.flush();
           ouputStream.close();
       } catch (IOException e) {
           // TODO Auto-generated catch block
           e.printStackTrace();
       }

   }