标签:blog thold 像素 指定位置 功能 content 对象 beans class
之前写过一篇文章 《超详细的java生成excel文件并下载》,该文章虽然够详细,也行得通,但还是有一定的缺陷,该文章可以拆分成两个部分,一是指定位置生成excel文件,二是根据地址下载文件。缺陷的部分是会产生中间文件,而这个中间文件我们并不需要,如果每次下载的时候都会生成一个这样的文件,那久而久之岂不是浪费空间,而且生成文件之后再读取输出这样也耗时间。所以今天就对之前的文章进行优化处理下。
package com.test.demo.controllers; import com.test.demo.domain.entities.Address; import com.test.demo.services.ExcelService; import jxl.Workbook; import jxl.format.Alignment; import jxl.format.Border; import jxl.format.BorderLineStyle; import jxl.format.Colour; import jxl.format.*; import jxl.format.VerticalAlignment; import jxl.write.*; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; import org.springframework.web.context.request.RequestContextHolder; import org.springframework.web.context.request.ServletRequestAttributes; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.File; import java.io.FileInputStream; import java.io.InputStream; import java.io.OutputStream; import java.text.SimpleDateFormat; import java.util.List; /** * @author dyh * @create 2018-11-15 下午10:20 * @desc excle表格功能编写 **/ @RestController @RequestMapping("/excel") public class ExcelController { @Autowired private ExcelService excelService; /** * 下载文件 * * @return */ @RequestMapping({"/download"}) public void download() { ServletRequestAttributes requestAttributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes(); HttpServletResponse response = requestAttributes.getResponse(); HttpServletRequest request = requestAttributes.getRequest(); // 文件名 String filename = "地址列表.xls"; OutputStream out = null; try { // 下面几行是为了解决文件名乱码的问题 httpServletResponse.setHeader("Content-Disposition", "attachment;filename=" + new String(filename.getBytes(), "iso-8859-1")); httpServletResponse.setContentType("application/vnd.ms-excel;charset=UTF-8"); httpServletResponse.setHeader("Pragma", "no-cache"); httpServletResponse.setHeader("Cache-Control", "no-cache"); httpServletResponse.setDateHeader("Expires", 0); out = httpServletResponse.getOutputStream(); // 创建写工作簿对象,这里直接采用流输出,而不会再生成一个文件 WritableWorkbook workbook = Workbook.createWorkbook(out); // 工作表 WritableSheet sheet = workbook.createSheet("地址列表", 0); // 设置字体; WritableFont font = new WritableFont(WritableFont.ARIAL, 14, WritableFont.BOLD, false, UnderlineStyle.NO_UNDERLINE, Colour.BLACK); WritableCellFormat cellFormat = new WritableCellFormat(font); // 设置背景颜色; cellFormat.setBackground(Colour.WHITE); // 设置边框; cellFormat.setBorder(Border.ALL, BorderLineStyle.DASH_DOT); // 设置文字居中对齐方式; cellFormat.setAlignment(Alignment.CENTRE); // 设置垂直居中; cellFormat.setVerticalAlignment(VerticalAlignment.CENTRE); // 分别给1,5,6列设置不同的宽度; sheet.setColumnView(0, 15); sheet.setColumnView(4, 60); sheet.setColumnView(5, 35); // 给sheet电子版中所有的列设置默认的列的宽度; sheet.getSettings().setDefaultColumnWidth(20); // 给sheet电子版中所有的行设置默认的高度,高度的单位是1/20个像素点,但设置这个貌似就不能自动换行了 // sheet.getSettings().setDefaultRowHeight(30 * 20); // 设置自动换行; cellFormat.setWrap(true); // 单元格 Label label0 = new Label(0, 0, "ID", cellFormat); Label label1 = new Label(1, 0, "省", cellFormat); Label label2 = new Label(2, 0, "市", cellFormat); Label label3 = new Label(3, 0, "区", cellFormat); Label label4 = new Label(4, 0, "详细地址", cellFormat); Label label5 = new Label(5, 0, "创建时间", cellFormat); sheet.addCell(label0); sheet.addCell(label1); sheet.addCell(label2); sheet.addCell(label3); sheet.addCell(label4); sheet.addCell(label5); // 给第二行设置背景、字体颜色、对齐方式等等; WritableFont font2 = new WritableFont(WritableFont.ARIAL, 14, WritableFont.NO_BOLD, false, UnderlineStyle.NO_UNDERLINE, Colour.BLACK); WritableCellFormat cellFormat2 = new WritableCellFormat(font2); // 设置文字居中对齐方式; cellFormat2.setAlignment(Alignment.CENTRE); // 设置垂直居中; cellFormat2.setVerticalAlignment(VerticalAlignment.CENTRE); cellFormat2.setBackground(Colour.WHITE); cellFormat2.setBorder(Border.ALL, BorderLineStyle.THIN); cellFormat2.setWrap(true); // 记录行数 int n = 1; // 查找所有地址 List<Address> addressList = excelService.findAll(); if (addressList != null && addressList.size() > 0) { // 遍历 for (Address a : addressList) { SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); String createTime = sdf.format(a.getCreateTime()); Label lt0 = new Label(0, n, a.getId() + "", cellFormat2); Label lt1 = new Label(1, n, a.getProvince(), cellFormat2); Label lt2 = new Label(2, n, a.getCity(), cellFormat2); Label lt3 = new Label(3, n, a.getArea(), cellFormat2); Label lt4 = new Label(4, n, a.getAddress(), cellFormat2); Label lt5 = new Label(5, n, createTime, cellFormat2); sheet.addCell(lt0); sheet.addCell(lt1); sheet.addCell(lt2); sheet.addCell(lt3); sheet.addCell(lt4); sheet.addCell(lt5); n++; } } //开始执行写入操作 workbook.write(); //关闭流 workbook.close(); out.close(); } catch (Exception e) { e.printStackTrace(); } } }
上面的代码就是关键的文件,至于一些其它的配置,以及可用的demo,可在前一篇文章 《超详细的java生成excel文件并下载》 上下载下来稍稍一下。
生成 excel 直接用 httpServletResponse 输出
标签:blog thold 像素 指定位置 功能 content 对象 beans class
原文地址:https://www.cnblogs.com/dyh2025/p/9966793.html