导出html文件数据

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前言

springBoot项目实现在线导出html文件数据的功能。

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一、实现代码

1.controller层

@GetMapping("/record/_export")
@ApiOperation("查询记录导出")
public void recordExport(HttpServletResponse response, RecordSearchRequest query) throws IOException {
        ruleVerifyResultService.recordExport(response, query);
    }

RecordSearchRequest为请求查询条件，根据条件导出对应的记录。

2.接口层

public interface ResultService extends IService<RuleVerifyResultEntity> {
 /**
     * 记录导出
     * @param query
     * @return
     */
    void recordExport(HttpServletResponse response, RecordSearchRequest query) throws IOException;
}

3.接口实现类

@Override
public void queryRecordExport(HttpServletResponse response, RuleVerifyRecordSearchRequest query) throws IOException {
        LocalDateTime startExecuteTime = null;
        LocalDateTime endExecuteTime = null;
        //设置导出文件名称
        String fileName = "检验记录列表数据";
        if (ObjectUtils.isNotEmpty(query.getExecuteStartTime())) {
            startExecuteTime = query.getExecuteStartTime().atStartOfDay();
            endExecuteTime = query.getExecuteStartTime().atTime(23, 59, 59);
        }
       //查询需要导出的数据，用list集合接收
        List<RuleVerifyRecordEntity> recordList = ruleVerifyRecordMapper.selectList(Wrappers.<RuleVerifyRecordEntity>lambdaQuery().
                // 关键字搜索
                and(StringUtils.isNotEmpty(query.getKeywords()), wrapper -> 
	          wrapper.like(RuleVerifyRecordEntity::getTableName, query.getKeywords()).
                        or().like(RuleVerifyRecordEntity::getTableRemark, query.getKeywords()).
                        or().like(RuleVerifyRecordEntity::getDatasourceName, query.getKeywords())
                )
                orderByDesc(RuleVerifyRecordEntity::getExecuteStartTime)
        );

        //2.导出html数据
        if (ObjectUtils.equals(ExportTypeEnum.HTML.getValue(), query.getExportType())) {
            //构建文件信息
            StringBuilder table = this.buildTableInfo(recordList);
            InputStream inputStream = null;
            FileInputStream fileInputStream = null;
            ServletOutputStream outputStream = null;
            try {
                //string字符串转输入流
                inputStream = FileUtil.getInputStream(table.toString());
                //字节输入流转文件输入流
                fileInputStream = FileUtil.convertToFileInputStream(inputStream);
                //给浏览器设置响应头：Content-Disposition告诉浏览器以附件的形式打开这个文件
                response.setHeader("Content-Disposition", "attachment;filename=" + URLEncoder.encode(fileName + ".html", "UTF-8"));
                //给浏览器设置响应头：文件类型
                response.setContentType("application/octet-stream;charset=utf-8");
                //从response中获取输出流
                outputStream = response.getOutputStream();
                //进行流拷贝操作
                FileUtil.copyStream(fileInputStream, outputStream);
                outputStream.flush();
            } catch (IOException e) {
                log.error(e.getMessage());
                e.printStackTrace();
            } finally {
               //关闭资源文件
                try{
                    inputStream.close();
                    fileInputStream.close();
                    outputStream.close();
                }catch(Exception e){
                    e.printStackTrace();
                }
            }
        }


	   private StringBuilder buildTableInfo(List<RuleVerifyRecordEntity> recordList){
        StringBuilder table = new StringBuilder();
        // 添加table标签
        table.append("<table>\n");
        // 生成表头
        table.append("<tr>\n");
        table.append("<th>" + "表名称" + "</th>");
        table.append("<th>" + "规则异常" + "</th>");
        table.append("<th>" + "执行状态" + "</th>");
        table.append("<th>" + "调度信息" + "</th>");
        table.append("<th>" + "开始时间" + "</th>");
        table.append("<th>" + " " + "</th>\n");
        table.append("<th>" + "结束时间" + "</th>");
        table.append("</tr>\n");
        // 生成HTML表格
        // 生成表格数据
        for (RuleVerifyRecordEntity row : recordList) {
            table.append("<tr>\n");
            table.append("<td>" + row.getTableName() + "</td>\n");
            table.append("<td>" + row.getRuleCount()) + "</td>\n");
            table.append("<td>" + (ObjectUtils.isNotEmpty(row.getExecuteStatus()) ? row.getExecuteStatus().toString() : null) + "</td>\n");
            table.append("<td>" + row.getSchedulerInfo() + " " + "</td>\n");
            table.append("<td>" + DateTimeUtil.toDateTimeStr(ObjectUtils.isNotEmpty(row.getExecuteStatus()) ? row.getExecuteStartTime() : LocalDateTime.now()) + "</td>\n");
            table.append("<td>" + " " + "</td>\n");
            table.append("<td>" + DateTimeUtil.toDateTimeStr(ObjectUtils.isNotEmpty(row.getExecuteEndTime()) ? row.getExecuteEndTime() : LocalDateTime.now()) + "</td>\n");
            table.append("</tr>\n");
        }
        table.append("</table>");
        return table;
    }
}


    

4.FileUtil 工具类

import javax.servlet.ServletOutputStream;
import java.io.*;
import java.nio.charset.StandardCharsets;


public class FileUtil {
    //string字符串转输入流
    public static InputStream getInputStream(String str) {
        if (str != null && !"".equals(str.trim())) {
            try {
                ByteArrayInputStream inputStream = new ByteArrayInputStream(str.getBytes(StandardCharsets.UTF_8));
                return inputStream;
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
        return null;
    }

    //字节输入流转文件输入流
    public static FileInputStream convertToFileInputStream(InputStream inputStream) throws IOException {
        File tempFile = File.createTempFile("temp", ".tmp");
        tempFile.deleteOnExit();

        try (FileOutputStream outputStream = new FileOutputStream(tempFile)) {
            byte[] buffer = new byte[1024];
            int bytesRead;
            while ((bytesRead = inputStream.read(buffer)) != -1) {
                outputStream.write(buffer, 0, bytesRead);
            }
        }
        return new FileInputStream(tempFile);
    }

    //数据写入输出流
    public static void copyStream(FileInputStream fileInputStream, ServletOutputStream outputStream) throws IOException {
        int len = 0;
        byte[] arr = new byte[1024];
        while ((len = fileInputStream.read(arr)) != -1) {
            outputStream.write(arr, 0, len);
        }
    }
}

二、文件导出效果

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总结

本次实现了html文件的导出功能，下节接着实现xml文件的导出功能。