使用POI导出excel，完美兼容2003及2007以上版本，购物车原理

工作需要。话不多说。

我们来看传统的poi。使用HSSFWorkbook创建2003格式为xls后缀的文档。如下：

public String toTotal() {
		String strs = "'40288b163a72fd15013a730d44430004','40288b163a72fd15013a730d44430004'," + "'40288b163a72fd15013a730d44430004','40288b163a72fd15013a730d44430004',"
				+ "'40288b163a72fd15013a730d44430004','40288b163a72fd15013a730d44430004'," + "'40288b163a72fd15013a730d44430004','40288b163a72fd15013a730d44430004',"
				+ "'40288b163a72fd15013a730d44430004','40288b163a72fd15013a730d44430004'";
		String sql1 = "select id,question_note,item1,item2,item3,item4,item5,item6,item7,item8" + ",item9,item10,item11 from PR_VOTE_QUESTION where FK_VOTE_PAPER_ID in (" + strs + ")";
		String s1 = "SELECT DISTINCT ip from pr_vote_ANSWER where questionid=";
		dbpool db = new dbpool();
		MyResultSet m1 = null;
		MyResultSet y1 = null;
		MyResultSet x1 = null;
		try {
			m1 = db.executeQuery(sql1);
			HSSFWorkbook wb = new HSSFWorkbook();// 建立新HSSFWorkbook对象
			HSSFSheet sheet = wb.createSheet("total");// 建立新的sheet对象
			// HSSFCellStyle cellStyle = wb.createCellStyle();//建立新的cell样式---日期用
			// cellStyle.setDataFormat(HSSFDataFormat.getFormat("m/d/yy
			// h:mm"));//设置cell样式为定制的日期格式
			// HSSFCell dCell =row.createCell((short)4);
			// dCell.setCellvalue(new Date());//设置cell为日期类型的值
			// dCell.setCellStyle(cellStyle); //设置该cell日期的显示格式
			HSSFRow row = sheet.createRow(0);
			setCellGBKValue(row.createCell((short) 0), "用户IP");
			setCellGBKValue(row.createCell((short) 1), "题目");
			setCellGBKValue(row.createCell((short) 2), "选项");
			// 四个参数分别是：起始行，起始列，结束行，结束列
			sheet.addMergedRegion(new Region(0, (short) 2, 0, (short) 13));
			int i = 1;
			while (m1.next()) {
				String id = m1.getString("id");
				String question_note = m1.getString("question_note");
				question_note = question_note.replace("
", "").replace("
", "").replace(" ", "").replace("
", "");
				System.out.println("题目：" + question_note);
				HSSFRow row2 = sheet.createRow((short) i);// 建立新行
				HSSFCell cell = row2.createCell((short) 1);// 建立新cell
				setCellGBKValue(cell, question_note);// 设置cell的整数类型的值
				// HSSFRow row1 = sheet.createRow(++i);
				// setCellGBKValue(row2.createCell((short) 1),"");
				setCellGBKValue(row2.createCell((short) 2), m1.getString("item1"));
				setCellGBKValue(row2.createCell((short) 3), m1.getString("item2"));
				setCellGBKValue(row2.createCell((short) 4), m1.getString("item3"));
				setCellGBKValue(row2.createCell((short) 5), m1.getString("item4"));
				setCellGBKValue(row2.createCell((short) 6), m1.getString("item5"));
				setCellGBKValue(row2.createCell((short) 7), m1.getString("item6"));
				setCellGBKValue(row2.createCell((short) 8), m1.getString("item7"));
				setCellGBKValue(row2.createCell((short) 9), m1.getString("item8"));
				setCellGBKValue(row2.createCell((short) 10), m1.getString("item9"));
				setCellGBKValue(row2.createCell((short) 11), m1.getString("item10"));
				setCellGBKValue(row2.createCell((short) 12), m1.getString("item11"));
				y1 = db.executeQuery(s1 + "'" + id + "'");
				while (y1.next()) {
					String str = "select a.ANSWERID ans,case when a.ANSWERID='1' then Q1.item1 " + " when a.ANSWERID='2' then Q1.item2 when a.ANSWERID='3' then Q1.item3 "
							+ " when a.ANSWERID='4' then Q1.item4 when a.ANSWERID='5' then Q1.item5 " + " when a.ANSWERID='6' then Q1.item6 when a.ANSWERID='7' then Q1.item7 "
							+ " when a.ANSWERID='8' then Q1.item8 when a.ANSWERID='9' then Q1.item9 " + " when a.ANSWERID='10' then Q1.item10 when a.ANSWERID='11' then Q1.item11 "
							+ " end usr_get from pr_vote_ANSWER a " + "INNER JOIN  PR_VOTE_QUESTION q1 on q1.id=a.questionid ";
					String ip = y1.getString("ip");
					System.out.println("用户ip:" + ip);
					HSSFRow row3 = sheet.createRow((short) ++i);// 建立新行
					HSSFCell cell3 = row3.createCell((short) 0);// 建立新cell
					setCellGBKValue(cell3, ip);// 设置cell的整数类型的值
					str += " where questionid='" + id + "' and ip='" + ip + "'";
					x1 = db.executeQuery(str);
					while (x1.next()) {
						int ans = Integer.valueOf(x1.getString("ans"));
						System.out.println("用户选项：" + ans);
						HSSFCell cell4 = row3.createCell((short) (ans + 1));// 建立新cell
						setCellGBKValue(cell4, x1.getString("usr_get"));// 设置cell的值
					}
					db.close(x1);
				}
				db.close(y1);
				i++;
			}
			db.close(m1);
			FileOutputStream fileOut = new FileOutputStream("E:\\调查问卷-统计信息.xls");
			wb.write(fileOut);
			fileOut.close();

		} catch (SQLException e) {
			e.printStackTrace();
			if (db != null && x1 != null) {
				db.close(x1);
			}
			if (db != null && y1 != null) {
				db.close(y1);
			}
			if (db != null && m1 != null) {
				db.close(m1);
			}
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		} finally {
			if (db != null && x1 != null) {
				db.close(x1);
			}
			if (db != null && y1 != null) {
				db.close(y1);
			}
			if (db != null && m1 != null) {
				db.close(m1);
			}
		}
		return null;
	}

类似的创建2007以及版本的xlsx则为XSSFWorkbook。

当然除此之外，我们可以有其它的选择。使用SXSSFWorkbook。目前我只知道poi3.8以上版本有这个玩意。其它没试过。

下载下来后，你可以看有关它的记录。用来输出W级别以上的sql是个不错的选择。数据保存在内存中，它可以及时输出缓冲数据，指定内存中可以放入的数据，超过这个数据我们就进行输出。

//导出每个IP用户的调查问卷 lizhuang
	public String toDo() {
		String strs = "'40288b163a72fd15013a730d44430004','40288b163a72fd15013a730d44430004'," + "'40288b163a72fd15013a730d44430004','40288b163a72fd15013a730d44430004',"
				+ "'40288b163a72fd15013a730d44430004','40288b163a72fd15013a730d44430004'," + "'40288b163a72fd15013a730d44430004','40288b163a72fd15013a730d44430004',"
				+ "'40288b163a72fd15013a730d44430004','40288b163a72fd15013a730d44430004'";
		String sql1 = "select id,question_note,item1,item2,item3,item4,item5,item6,item7,item8" + ",item9,item10,item11 from PR_VOTE_QUESTION where FK_VOTE_PAPER_ID in (" + strs + ")";
		String s1 = "SELECT DISTINCT ip from pr_vote_ANSWER where questionid=";
		dbpool db = new dbpool();
		MyResultSet m1 = null;
		MyResultSet y1 = null;
		MyResultSet x1 = null;
		Map ips = new HashMap();//string对应用户IP，row存储用户所在的行。购物车原型【存储用户ID和商品】
		BufferedInputStream bis = null;
		BufferedOutputStream bos = null;
		try {
			m1 = db.executeQuery(sql1);
			SXSSFWorkbook wb = new SXSSFWorkbook(100);// 只在内存中保留100行数据，大数据时使用。兼容HSSFWorkbook2003和XSSFWorkbook2007
			wb.setCompressTempFiles(true); // temp files will be gzipped
			Sheet sheet = wb.createSheet("total");// 建立新的sheet对象
			sheet.setDefaultColumnWidth((short) 15);
			Row row = sheet.createRow(0);
			setCellGBKValue(row.createCell((short) 0), "用户IP");
			// 合并单元格四个参数分别是：起始行，起始列，结束行，结束列
			// sheet.addMergedRegion(new Region(0,(short)2,0,(short)13));
			int j = 1;//列的坐标，递增
			int k=1;//每个用户一行数据
			int cols = 2;// 默认4列
			while (m1.next()) {
				String id = m1.getString("id");
				//取标题
				String question_note = m1.getString("question_note");
				question_note = question_note.replace("
", "").replace("
", "").replace(" ", "").replace("
", "");
				setCellGBKValue(row.createCell((short) j++), "");
				setCellGBKValue(row.createCell((short) j++), question_note);
				//取出选项，最多11个，可扩展。
				setCellGBKValue(row.createCell((short) j++), m1.getString("item1"));
				setCellGBKValue(row.createCell((short) j++), m1.getString("item2"));
				String item3 = m1.getString("item3");
				String item4 = m1.getString("item4");
				String item5 = m1.getString("item5");
				String item6 = m1.getString("item6");
				String item7 = m1.getString("item7");
				String item8 = m1.getString("item8");
				String item9 = m1.getString("item9");
				String item10 = m1.getString("item10");
				String item11 = m1.getString("item11");
				if (item3 != null) {
					cols = 3;
					setCellGBKValue(row.createCell((short) j++), item3);
				}
				if (item4 != null) {
					cols = 4;
					setCellGBKValue(row.createCell((short) j++), item4);
				}
				if (item5 != null) {
					cols = 5;
					setCellGBKValue(row.createCell((short) j++), item5);
				}
				if (item6 != null) {
					cols = 6;
					setCellGBKValue(row.createCell((short) j++), item6);
				}
				if (item7 != null) {
					cols = 7;
					setCellGBKValue(row.createCell((short) j++), item7);
				}
				if (item8 != null) {
					cols = 8;
					setCellGBKValue(row.createCell((short) j++), item8);
				}
				if (item9 != null) {
					cols = 9;
					setCellGBKValue(row.createCell((short) j++), item9);
				}
				if (item10 != null) {
					cols = 10;
					setCellGBKValue(row.createCell((short) j++), item10);
				}
				if (item11 != null) {
					cols = 11;
					setCellGBKValue(row.createCell((short) j++), item11);
				}
				y1 = db.executeQuery(s1 + "'" + id + "'");
				Row row3 = null;
				while (y1.next()) {
					String str = "select a.ANSWERID ans,case when a.ANSWERID='1' then Q1.item1 " + " when a.ANSWERID='2' then Q1.item2 when a.ANSWERID='3' then Q1.item3 "
							+ " when a.ANSWERID='4' then Q1.item4 when a.ANSWERID='5' then Q1.item5 " + " when a.ANSWERID='6' then Q1.item6 when a.ANSWERID='7' then Q1.item7 "
							+ " when a.ANSWERID='8' then Q1.item8 when a.ANSWERID='9' then Q1.item9 " + " when a.ANSWERID='10' then Q1.item10 when a.ANSWERID='11' then Q1.item11 "
							+ " end usr_get from pr_vote_ANSWER a " + "left JOIN  PR_VOTE_QUESTION q1 on q1.id=a.questionid ";
					String ip = y1.getString("ip");
					if (!ips.containsKey(ip)) {
						row3 = sheet.createRow((short) k++);// 建立新行，每行存储用户IP和答案
						ips.put(ip, row3);// 利用购物车原理，只不过购物车存储的是每件商品，这里记录上次的行。
					} else {
						row3 = ips.get(ip);// 如果有商品就取出商品，计算商品数量++，金额++，此处取出上次的行
					}
					setCellGBKValue(row3.createCell((short) 0), ip);// 设置IP
					str += " where questionid='" + id + "' and ip='" + ip + "'";
					x1 = db.executeQuery(str);
					while (x1.next()) {
						int ans = Integer.valueOf(x1.getString("ans"));
						setCellGBKValue(row3.createCell((short) (j - 1 - cols + ans)), x1.getString("usr_get"));
					}
					db.close(x1);
					str = null;// destroy this,collection rubbish
				}
				db.close(y1);
				if (k % 100 == 0) {
					((SXSSFSheet) sheet).flushRows(100);// flushRows(0)
				}
			}
			db.close(m1);
			ByteArrayOutputStream os = new ByteArrayOutputStream();
			wb.write(os);// 将excel写入流
			byte[] content = os.toByteArray();
			InputStream is = new ByteArrayInputStream(content);
			HttpServletResponse response = ServletActionContext.getResponse();
			response.reset();
			response.setContentType("application/vnd.ms-excel;charset=utf-8"); // msexcel
			response.setHeader("Content-Disposition", "attachment;filename=" + new String("调查问卷-统计信息.xlsx".getBytes(), "iso-8859-1"));
			ServletOutputStream out = response.getOutputStream();
			bis = new BufferedInputStream(is);
			bos = new BufferedOutputStream(out);
			byte[] buff = new byte[2048];
			int bytesRead;
			// Simple read/write loop.
			while (-1 != (bytesRead = bis.read(buff, 0, buff.length))) {
				bos.write(buff, 0, bytesRead);
			}
			out.close();
			//直接写到本地，测试用
			//FileOutputStream fileOut = new FileOutputStream("E:\\调查问卷-统计信息.xlsx");
			//wb.write(fileOut);
			//fileOut.close();
		} catch (SQLException e) {
			e.printStackTrace();
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		} finally {
			if (db != null && x1 != null) {
				db.close(x1);
			}
			if (db != null && y1 != null) {
				db.close(y1);
			}
			if (db != null && m1 != null) {
				db.close(m1);
			}
			try {
				if (bis != null) {
					bis.close();
				}
				if (bos != null) {
					bos.close();
				}
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
		return null;
	}

	private static void setCellGBKValue(Cell cell, String value) {
		cell.setCellType(Cell.CELL_TYPE_STRING);// 设置CELL的编码信息
		cell.setCellValue(value);
	}

这是依据poi的文档做出来的，相应的包路径：

import org.apache.poi.hssf.usermodel.HSSFCell;
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.Region;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.xssf.streaming.SXSSFSheet;
import org.apache.poi.xssf.streaming.SXSSFWorkbook;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;

打印后的效果为：

之所以使用2007，是因为它支持最大的列数为16000多列。而这正好符合我的需求。客户要求所有用户的回答在同一行显示。显然用2003是不够用的。2003最大才256列。

变态的需求产生这样的效果。

答案的定位显示我没有使用2维数组，因为2维数据需要循环。而我不喜欢在程序中太多的使用循环，此处使用购物车存入商品的原理实现了数据的定位。

算是一种学习吧。记录于此。