使用easyexcel将csv转为excel

背景

供应商系统下载的csv文件不支持域控（主要是第三方wps服务不能对csv文件加密，但是可以对office系列产品进行权限访问的加密控制）。因此思路就改为现将csv文件转为excel文件，然后对excel文件进行加域控制。本文主要介绍如何将csv文件转为excel文件。

要求

Csv文件可能比较大，达到40-60M，需要控制内存使用率;
1. 考虑接口的并发，需要进行接口的限流

方案

采用alibaba的easyexcel，降低内存占用率，根据压测结果，设置合理的接口限流参数（限流
本文不再介绍，可以使用java注解+redis+lua, 或者nginx限流等）

  #### 代码

CsvController

java 复制代码

package com.xxx.xxx.controller;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Future;

import javax.annotation.Resource;
import javax.servlet.http.HttpServletResponse;

import com.xxx.xxx.common.utils.EasyExcelUtil;
import com.xxx.xxx.common.utils.ObjectUtil;
import com.xxx.xxx.service.ExcelAnalysisService;

import lombok.extern.slf4j.Slf4j;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

/**
 * description:
 *
 * @author: lgq
 * @create: 2024-04-16 11:06
 */
@Slf4j
@RestController
@RequestMapping("/csv")
public class CsvController {
    @Resource
    private ExcelAnalysisService excelAnalysisService;

    /**
     * 读取传入的csv  文本的内容可以存入数据库
     *
     * @param file
     * @return
     */
    @PostMapping("/uploadCsvAndImportExcel")
    public void uploadCsvAndImportExcel(@RequestParam("file") MultipartFile file, HttpServletResponse response) {
        String[] splitName = file.getOriginalFilename().split(".csv");
        if (ObjectUtil.isEmpty(splitName) || ObjectUtil.isEmpty(splitName[0])) {
            return;
        }
        EasyExcelUtil.setResponseParam(response, splitName[0]);
        long startTime = System.currentTimeMillis();
        log.info("导出开始时间:{}", startTime);

        try {
            // 输出流可以为本地文件
//          OutputStream outputStream = new FileOutputStream("D:\\templateExcel\\filename.xlsx");
            OutputStream outputStream = response.getOutputStream();
            InputStream inputStream = file.getInputStream();
            Future<String> future = excelAnalysisService.csv2Excel(inputStream, outputStream);
            future.get();
        } catch (IOException ioException) {
            log.error("csv转为excel出错！", ioException.getMessage());
            ioException.printStackTrace();
        } catch (InterruptedException interruptedException) {
            log.error("csv转为excel出错！", interruptedException.getMessage());
            interruptedException.printStackTrace();
        } catch (ExecutionException executionException) {
            log.error("csv转为excel出错！", executionException.getMessage());
            executionException.printStackTrace();
        }
        // 导出时间结束
        long endTime = System.currentTimeMillis();
        log.info("导出结束时间:{}", endTime + "ms");
        log.info("导出所用时间:{}", (endTime - startTime) / 1000 + "秒");
    }

}

EasyExcelGeneralCsvListener
4.

java 复制代码

package com.xxx.xxx.listener;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Map;

import com.alibaba.excel.ExcelWriter;
import com.alibaba.excel.context.AnalysisContext;
import com.alibaba.excel.event.AnalysisEventListener;
import com.alibaba.excel.write.metadata.WriteSheet;
import com.xxx.xxx.constants.ExcelConstants;

/**
 * description:
 *
 * @author: lgq
 * @create: 2024-04-16 11:25
 */
public class EasyExcelGeneralCsvListener extends AnalysisEventListener<Map<Integer, String>>  {
    /**
     * 用于存储读取的数据
     */
    private List<Map<Integer, String>> dataList = new ArrayList<>();

    private ExcelWriter excelWriter;

    private WriteSheet writeSheet;

    public EasyExcelGeneralCsvListener() {
    }

    public EasyExcelGeneralCsvListener(ExcelWriter excelWriter, WriteSheet writeSheet) {
        this.excelWriter = excelWriter;
        this.writeSheet = writeSheet;
    }

    @Override
    public void invoke(Map<Integer, String> data, AnalysisContext context) {
        // 数据add进入集合
        dataList.add(data);
        // size是否为2000条:这里其实就是分批.当数据等于2k的时候执行一次写入excel
        if (dataList.size() >= ExcelConstants.PER_WRITE_EXCEL_ROW_COUNT) {
            save2Excel();
            // 清理集合便于GC回收
            dataList.clear();
        }
    }

    @Override
    public void invokeHeadMap(Map<Integer, String> headers, AnalysisContext context) {
        List<List<String>> titles = new ArrayList<>();
        for (int i = 0; i < headers.size(); i++) {
            titles.add(Collections.singletonList(headers.get(i)));
        }
        this.writeSheet.setHead(titles);
    }

    /**
     * 保存数据到 excel
     */
    private void save2Excel() {
        if (dataList.size() > 0) {
            List<List<String>> consumerDataList = new ArrayList<>();
            dataList.stream().forEach( e ->
                    {
                        List<String> objects = new ArrayList<>();
                        for (int i = 0; i < e.size(); i++) {
                            objects.add(e.get(i));
                        }
                        consumerDataList.add(objects);
                    }

            );
            this.excelWriter.write(consumerDataList, writeSheet);
        }
    }

    /**
     * Excel 中所有数据解析完毕会调用此方法
     */
    @Override
    public void doAfterAllAnalysed(AnalysisContext context) {
        save2Excel();
        dataList.clear();
    }

}

VisiableThreadPoolTaskExecutor
5.

java 复制代码

package com.xxx.xxx.task;

import java.util.concurrent.Callable;
import java.util.concurrent.Future;
import java.util.concurrent.ThreadPoolExecutor;

import lombok.extern.slf4j.Slf4j;
import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;
import org.springframework.util.concurrent.ListenableFuture;

/**
 * description:VisiableThreadPoolTaskExecutor
 *
 * @author: lgq
 * @create: 2024-04-17 10:52
 */
@Slf4j
public class VisiableThreadPoolTaskExecutor extends ThreadPoolTaskExecutor {
    private void showThreadPoolInfo(String prefix){
        ThreadPoolExecutor threadPoolExecutor = getThreadPoolExecutor();

        if(null==threadPoolExecutor){
            return;
        }

        log.info("{}, {},taskCount [{}], completedTaskCount [{}], activeCount [{}], queueSize [{}]",
                this.getThreadNamePrefix(),
                prefix,
                threadPoolExecutor.getTaskCount(),
                threadPoolExecutor.getCompletedTaskCount(),
                threadPoolExecutor.getActiveCount(),
                threadPoolExecutor.getQueue().size());
    }

    @Override
    public void execute(Runnable task) {
        showThreadPoolInfo("1. do execute");
        super.execute(task);
    }

    @Override
    public void execute(Runnable task, long startTimeout) {
        showThreadPoolInfo("2. do execute");
        super.execute(task, startTimeout);
    }

    @Override
    public Future<?> submit(Runnable task) {
        showThreadPoolInfo("1. do submit");
        return super.submit(task);
    }

    @Override
    public <T> Future<T> submit(Callable<T> task) {
        showThreadPoolInfo("2. do submit");
        return super.submit(task);
    }

    @Override
    public ListenableFuture<?> submitListenable(Runnable task) {
        showThreadPoolInfo("1. do submitListenable");
        return super.submitListenable(task);
    }

    @Override
    public <T> ListenableFuture<T> submitListenable(Callable<T> task) {
        showThreadPoolInfo("2. do submitListenable");
        return super.submitListenable(task);
    }
}

复制代码

ExcelAnalysisService

java 复制代码

package com.xxx.xxx.service;

import java.io.OutputStream;
import java.io.InputStream;
import java.util.concurrent.Future;

/**
 * description:excel文档分析处理类
 *
 * @author: lgq
 * @create: 2024-04-17 11:42
 */
public interface ExcelAnalysisService {
    /**
     * csv文档转为excel文档
     */
    Future<String> csv2Excel(InputStream inputStream, OutputStream outputStream);
}

ExcelAnalysisServiceImpl
7.

java 复制代码

package com.xxx.xxx.service.impl;

import java.io.OutputStream;
import java.nio.charset.Charset;

import com.alibaba.excel.EasyExcel;
import com.alibaba.excel.ExcelWriter;
import com.alibaba.excel.support.ExcelTypeEnum;
import com.alibaba.excel.write.metadata.WriteSheet;
import com.xxx.xxx.listener.EasyExcelGeneralCsvListener;
import com.xxx.xxx.service.ExcelAnalysisService;

import lombok.extern.slf4j.Slf4j;
import java.io.InputStream;
import java.util.concurrent.Future;

import org.springframework.scheduling.annotation.Async;
import org.springframework.scheduling.annotation.AsyncResult;
import org.springframework.stereotype.Service;

/**
 * description:ExcelAnalysisService实现类
 *
 * @author: lgq
 * @create: 2024-04-17 14:53
 */
@Service
@Slf4j
public class ExcelAnalysisServiceImpl implements ExcelAnalysisService {

    @Async("asyncExcelAnalysisServiceExecutor")
    @Override
    public Future<String> csv2Excel(InputStream inputStream, OutputStream outputStream) {
        try {
            ExcelWriter writer = EasyExcel.write(outputStream).excelType(ExcelTypeEnum.XLSX).build();

            EasyExcel.read(inputStream, new EasyExcelGeneralCsvListener(writer, new WriteSheet()))
                    .excelType(ExcelTypeEnum.CSV)
                    .charset(Charset.forName("UTF-8"))
                    .sheet()
                    .doRead();

            writer.finish();
            outputStream.flush();
        } catch (Exception e) {
            log.error("csv转为excel出错！", e.getMessage());
            e.printStackTrace();
        } finally {
            if (outputStream != null) {
                try {
                    outputStream.close();
                } catch (Exception e) {
                    log.error("outputStream.close() -> csv转为excel出错！", e.getMessage());
                    e.printStackTrace();
                }
            }
            if (inputStream != null) {
                try {
                    inputStream.close();
                } catch (Exception e) {
                    log.error("inputStream.close() -> csv转为excel出错！", e.getMessage());
                    e.printStackTrace();
                }
            }
        }
        return new AsyncResult<>("task complete!");
    }
}

ExecutorConfig
8.

java 复制代码

package com.xxx.xxx.config;

import java.util.concurrent.Executor;
import java.util.concurrent.ThreadPoolExecutor;


import com.xxx.xxx.task.VisiableThreadPoolTaskExecutor;

import lombok.extern.slf4j.Slf4j;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.scheduling.annotation.EnableAsync;
import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;

/**
 * description:线程池配置类
 *
 * @author: lgq
 * @create: 2024-04-17 10:28
 */
@Configuration
@Slf4j
@EnableAsync
public class ExecutorConfig {
    private static int corePoolSize = Runtime.getRuntime().availableProcessors() + 1;
    private static int maxPoolSize = Runtime.getRuntime().availableProcessors() + 1;
    private static int queueCapacity = 100;
    private static final String namePrefix = "ExcelAnalysis";

    @Bean(name = "asyncExcelAnalysisServiceExecutor")
    public Executor asyncExcelServiceExecutor() {
        log.info("start asyncExcelAnalysisServiceExecutor----------------");
        //ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
        //使用可视化运行状态的线程池
        ThreadPoolTaskExecutor executor = new VisiableThreadPoolTaskExecutor();
        //配置核心线程数
        executor.setCorePoolSize(corePoolSize);
        //配置最大线程数
        executor.setMaxPoolSize(maxPoolSize);
        //配置队列大小
        executor.setQueueCapacity(queueCapacity);
        //配置线程池中的线程的名称前缀
        executor.setThreadNamePrefix(namePrefix);

        // rejection-policy：当pool已经达到max size的时候，如何处理新任务
        // CALLER_RUNS：不在新线程中执行任务，而是有调用者所在的线程来执行
        executor.setRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy());

        //执行初始化
        executor.initialize();
        log.info("end asyncExcelAnalysisServiceExecutor------------");
        return executor;
    }

}

ExcelConstants
9.

java 复制代码

package com.xxx.xxx.constants;

/**
 * description:线程池配置类
 *
 * @author: lgq
 * @create: 2024-04-17 10:28
 */
public class ExcelConstants {
    public static final Integer PER_SHEET_ROW_COUNT = 100*10000;
    public static final Integer PER_WRITE_ROW_COUNT = 20*10000;
    public static final Integer PER_WRITE_EXCEL_ROW_COUNT = 2 * 1000;
    public static final Integer GENERAL_ONCE_SAVE_TO_DB_ROWS_JDBC = 10*10000;
    public static final Integer GENERAL_ONCE_SAVE_TO_DB_ROWS_MYBATIS = 5*10000;
}

配置文件
10.

```java
spring:
  servlet:
    multipart:
      enabled: true
      max-file-size: 100MB # 单个文件的最大值
      max-request-size: 100MB # 上传文件总的最大值
```

pom依赖

```java
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>easyexcel</artifactId>
            <version>3.3.2</version>
        </dependency>
```

#### 压测

jvm参数（本地电脑，性能较差）
-Xms2g -Xmx2g
导出日志

性能监控

压测结果