报名系统网站开发,wordpress占用id,网站标题改动,个人网站做导购可以吗为什么要使用EasyExcel easyExcel是阿里巴巴下在POI的基础上二次开发的开源api#xff0c;以使用简单、节省内存著称。 POI由于在操作excel时是先将所有数据都读入内存后#xff0c;再写入文件#xff0c;比较消耗内存#xff0c;特别是大数据量时#xff0c;容易出现OOM…为什么要使用EasyExcel easyExcel是阿里巴巴下在POI的基础上二次开发的开源api以使用简单、节省内存著称。 POI由于在操作excel时是先将所有数据都读入内存后再写入文件比较消耗内存特别是大数据量时容易出现OOM EasyExcel 能大大减少占用内存的主要原因是在解析 Excel 时没有将文件数据一次性全部加载到内存中而是从磁盘上一行行读取数据逐个解析 而使用EasyExcel进行导出Excel时候可以根据模板进行生成Excel具体操作如下 maven依赖 dependencygroupIdcom.alibaba/groupIdartifactIdeasyexcel/artifactIdversion2.2.4/version /dependency注意easyexcel2.2.4版本的依赖包含poi的3.1.7版本的依赖 最终下载的Excel文件效果 1.根据要生成的文件格式创建模板文件放到resource目录下 2.创建对应数据实体类注意字段排序要和标题头排列顺序一致 package cn.test.user.excel;import com.alibaba.excel.annotation.format.DateTimeFormat; import com.alibaba.excel.annotation.format.NumberFormat; import com.alibaba.excel.annotation.write.style.ContentFontStyle; import com.alibaba.excel.annotation.write.style.ContentRowHeight; import com.alibaba.excel.annotation.write.style.ContentStyle; import lombok.AllArgsConstructor; import lombok.Data; import lombok.NoArgsConstructor; import org.apache.poi.ss.usermodel.HorizontalAlignment; import org.apache.poi.ss.usermodel.VerticalAlignment;import java.math.BigDecimal; import java.util.Date;/*** Author mark* CreateTime: 2023-12-12 14:59*/ Data NoArgsConstructor AllArgsConstructor ContentRowHeight(value (short)13.5) ContentFontStyle(fontName 宋体,fontHeightInPoints 11) public class TransactionDto {/*** 付款单号*/ContentStyle(horizontalAlignment HorizontalAlignment.LEFT,verticalAlignment VerticalAlignment.CENTER,wrapped true)private String paymentId;/*** 交易状态*/ContentStyle(horizontalAlignment HorizontalAlignment.LEFT,verticalAlignment VerticalAlignment.CENTER,wrapped true)ContentFontStyle(color 10,fontHeightInPoints 11)//红色private String tranState;/*** 交易金额*/ContentStyle(horizontalAlignment HorizontalAlignment.RIGHT,verticalAlignment VerticalAlignment.CENTER,wrapped true)NumberFormat(###,###,##0.00)private BigDecimal transAmt;/*** 交易时间*/ContentStyle(horizontalAlignment HorizontalAlignment.LEFT,verticalAlignment VerticalAlignment.CENTER,wrapped true)DateTimeFormat(yyyy-MM-dd HH:mm:ss)private Date transDate; } 3.编写下载excel代码 package cn.test.user.excel;import com.alibaba.excel.EasyExcel; import com.alibaba.excel.support.ExcelTypeEnum; import com.sun.deploy.net.URLEncoder;import javax.servlet.http.HttpServletResponse; import java.io.InputStream; import java.math.BigDecimal; import java.util.ArrayList; import java.util.Date;/*** Author mark* CreateTime: 2023-12-12 15:06*/ public class DownloadExcel {public static void main(String[] args) {}public static void downExcel(HttpServletResponse response){//构造数据ArrayListTransactionDto list new ArrayList();list.add(new TransactionDto(FX202311051000001, 交易成功, new BigDecimal(12202.15), new Date()));list.add(new TransactionDto(FX202311051000002, 交易失败, new BigDecimal(156.15), new Date()));list.add(new TransactionDto(FX202311051000003, 处理中, new BigDecimal(212202.15), new Date()));list.add(new TransactionDto(FX202311051000004, 交易成功, new BigDecimal(1889.15), new Date()));list.add(new TransactionDto(FX202311051000005, 交易成功, new BigDecimal(65.15), new Date()));//获取模板文件InputStream inputStream null;try {inputStream Thread.currentThread().getContextClassLoader().getResourceAsStream(template/交易信息下载模板.xlsx);} catch (Exception e) {//读取模板文件失败}//根据模板生成excel文件try {response.setHeader(Connection,keep-alive);response.addHeader(Content-Type,application/octet-stream;charsetutf-8);response.addHeader(Content-Disposition,attachment:filename URLEncoder.encode(交易信息下载.xlsx,utf-8));EasyExcel.write(response.getOutputStream(), TransactionDto.class).autoCloseStream(true).withTemplate(inputStream).excelType(ExcelTypeEnum.XLSX)//excel格式.needHead(false).sheet(交易信息).doWrite(list);} catch (Exception e) {//出错}} }