Java的Excel导出功能

以前用到的：

	<servlet>
		<description>
		</description>
		<display-name>ExcelServlet</display-name>
		<servlet-name>ExcelServlet</servlet-name>
		<servlet-class>
		*.excel.ExcelServlet</servlet-class>
	</servlet>
	<servlet-mapping>
		<servlet-name>ExcelServlet</servlet-name>
		<url-pattern>*.xls</url-pattern>
	</servlet-mapping>

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.log4j.Logger;
public class ExcelServlet extends HttpServlet {
	private final Logger log = Log4jUtil.getLogger(ExcelServlet.class);
	public void init() throws ServletException {
	}
	public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		response.setContentType("application/vnd.ms-excel");
		RequestPage page = new RequestPage(request, response, request.getSession());
		ExcelOperator operator = null;
		try {
			operator = getOperator(request.getServletPath());
			if (operator != null) {
				operator.execute(page);
			}
		} catch (Exception ex) {
			log.debug("导出excel出错：" + ex.toString());
			ex.printStackTrace();
		}
	}
	/**
	 * 根据不同的请求path获取不同的导出excel操作
	 * 
	 * @param path
	 * @return
	 */
	public ExcelOperator getOperator(String path) {
			return new ReportExcelExport();
		
	}
	
	public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		doGet(request, response);
	}
	public void destroy() {
	}
}

import java.io.IOException;
import jxl.write.WriteException;

public abstract class ExcelOperator {
	
	jxl.write.WritableWorkbook excel = null;
	int fieldCount = 0;
	public RequestPage page;
	public void execute(RequestPage page) throws WriteException,
			IndexOutOfBoundsException, IOException {
		this.page = page;
		excel = jxl.Workbook.createWorkbook(this.page.getResponse()
				.getOutputStream());
		excel.createSheet("sheet1", 0);
		setTitle(getTitle());
		writeContent(getContent());
		write();
	}
	private void setTitle(String[] fields) throws IndexOutOfBoundsException,
			WriteException {
		this.fieldCount = fields.length;
		for (int i = 0; i < fields.length; i++) {
			excel.getSheet(0).addCell(new jxl.write.Label(i, 0, fields[i]));
		}
	}
	private void writeContent(java.util.ArrayList cells)
			throws IndexOutOfBoundsException, WriteException {
		if (cells == null)
			return;
		for (int i = 1; i <= cells.size(); i++) {
			Object obj = cells.get(i - 1);
			for (int j = 0; j < fieldCount; j++) {
				excel.getSheet(0).addCell(
						new jxl.write.Label(j, i, getValue(obj, j)));
			}
		}
	}
	public abstract String getValue(Object obj, int index);
	public abstract String[] getTitle();
	public abstract java.util.ArrayList getContent();
	private void write() throws IOException, WriteException, IOException {
		excel.write();
		excel.close();
	}
}

import java.util.ArrayList;
import java.util.HashMap;
public class ReportExcelExport extends ExcelOperator {
	@Override
	public ArrayList getContent() {
	}
	/**
	 * 报表表头
	 */
	@Override
	public String[] getTitle() {
		return new String[] { "责任人ID","责任人","责任人角色","年份" };
	}
	/**
	 * 单元格的值
	 */
	@Override
	public String getValue(Object obj, int index) {
		switch (index) {
		case 0:
			return values.getUserId();
		
		default:
			return "";
		}
	}
}

ref:

		if (request.getHeader("User-Agent").indexOf("MSIE 5.5") != -1) {
			response.setHeader("Content-Disposition", "filename=" + fileName);
		} else {
			response.addHeader("Content-Disposition", "attachment;filename=" + fileName);
		}
		response.setCharacterEncoding("GBK");
		//response.setContentType("text/html;charset=GBK");
		ServletOutputStream stream = null;
		BufferedInputStream buf = null;
		FileInputStream fis = null;
		try {
			stream = response.getOutputStream();
			fis = new FileInputStream(file);
			buf = new BufferedInputStream(fis);
			byte[] readBytes = new byte[4096];
			int len = 0;
			while ((len = buf.read(readBytes)) != -1) {
				stream.write(readBytes, 0, len);
			}
			stream.flush();
			response.setStatus(HttpServletResponse.SC_OK);
			response.flushBuffer();
		} catch (Exception ex) {
			logger.info(ex.toString());
		} finally {
			if (stream != null) {
				try {
					stream.close();
				} catch (IOException e) {
					logger.info(e.toString());
					e.printStackTrace();
				}
			}
			if (buf != null) {
				try {
					buf.close();
				} catch (IOException e) {
					logger.info(e.toString());
					e.printStackTrace();
				}
			}
			if (fis != null) {
				try {
					fis.close();
				} catch (IOException e) {
					logger.info(e.toString());
					e.printStackTrace();
				}
			}
		}