Java实现导出Excel

      本文将介绍在Java Web中使用Apache POI实现管理系统中常见的导出Excel功能。

      首先在pom.xml中导入poi的依赖包：

	org.apache.poi
	poi
	3.6

      然后编写工具类ExcelUtil.java，具体内容及解释如下：

import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFCellStyle;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;

public class ExcelUtil {

	public static HSSFWorkbook getHSSFWorkbook(String sheetName, String[] title, String[][] values, HSSFWorkbook wb) {

		// 第一步，创建一个HSSFWorkbook，对应一个Excel文件
		if (wb == null) {
			wb = new HSSFWorkbook();
		}

		// 第二步，在workbook中添加一个sheet,对应Excel文件中的sheet
		HSSFSheet sheet = wb.createSheet(sheetName);

		// 第三步，在sheet中添加表头第0行,注意老版本poi对Excel的行数列数有限制
		HSSFRow row = sheet.createRow(0);

		// 第四步，创建单元格，并设置值表头 设置表头居中
		HSSFCellStyle style = wb.createCellStyle();
		style.setAlignment(HSSFCellStyle.ALIGN_CENTER); // 创建一个居中格式

		// 声明列对象
		HSSFCell cell = null;

		// 创建标题
		for (int i = 0; i < title.length; i++) {
			cell = row.createCell(i);
			cell.setCellValue(title[i]);
			cell.setCellStyle(style);
		}

		// 创建内容
		for (int i = 0; i < values.length; i++) {
			row = sheet.createRow(i + 1);
			for (int j = 0; j < values[i].length; j++) {
				// 将内容按顺序赋给对应的列对象
				row.createCell(j).setCellValue(values[i][j]);
			}
		}
		return wb;
	}
}

      最后直接在controller中使用即可，这里笔者使用购房网站的信息作为例子，在实现时需要根据业务的数据修改下面方法：

@RequestMapping(value = "/export")
@ResponseBody
public void export(HttpServletRequest request, HttpServletResponse response) throws Exception {
	//获取数据
	Map data = requirementService.query(null);
	List list = (List) data.get("requirements");
	//excel标题
	String[] title = {"id","姓名","手机号","城市","县区","房源","地铁线","地铁站","售价","面积","房型","用途","权属","楼层","朝向",
			"楼龄","有无电梯","装修","咨询时间","备注"};
	//excel文件名
	String fileName = "购房需求信息表"+System.currentTimeMillis()+".xls";
	//sheet名
	String sheetName = "购房需求信息表";
	
	String[][] content = new String[list.size()+1][title.length];
	for (int i = 0; i < list.size(); i++) {
		Requirement r = list.get(i);
		System.out.println(r.toString());
		content[i][0] = r.getId()+"";
		content[i][1] = r.getUsername();
		content[i][2] = r.getPhone();
		content[i][3] = r.getCity();
		content[i][4] = r.getDistrict();
		content[i][5] = r.getVillage();
		content[i][6] = r.getLineNum();
		content[i][7] = r.getStationName();
		content[i][8] = r.getPrice();
		content[i][9] = r.getSquareMeter();
		content[i][10] = r.getHouseKind();
		content[i][11] = r.getUasge();
		content[i][12] = r.getOwnerShip();
		content[i][13] = r.getFloor();
		content[i][14] = r.getDirection();
		content[i][15] = r.getAge();
		content[i][16] = r.getElevator();
		content[i][17] = r.getDecoration();
		content[i][18] = sdf.format(r.getDate());
		content[i][19] = r.getRemark();
		}
	//创建HSSFWorkbook 
	HSSFWorkbook wb = ExcelUtil.getHSSFWorkbook(sheetName, title, content, null);
	//响应到客户端
	try {
		this.setResponseHeader(response, fileName);
		OutputStream os = response.getOutputStream();
			wb.write(os);
			os.flush();
			os.close();
 	} catch (Exception e) {
 		e.printStackTrace();
 	}
}

//发送响应流方法
public void setResponseHeader(HttpServletResponse response, String fileName) {
    try {
        try {
            fileName = new String(fileName.getBytes(),"ISO8859-1");
        } catch (UnsupportedEncodingException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        response.setContentType("application/octet-stream;charset=ISO8859-1");
        response.setHeader("Content-Disposition", "attachment;filename="+ fileName);
        response.addHeader("Pargam", "no-cache");
        response.addHeader("Cache-Control", "no-cache");
    } catch (Exception ex) {
        ex.printStackTrace();
    }
}

      部署Java Web后直接访问就可以生成并下载Excel表格了。So easy !