Csv--01--ExportUtil 写文件

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ExportUtil

import com.alibaba.fastjson.JSON;
import com.google.common.collect.Lists;

import org.apache.commons.lang3.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;
import org.springframework.util.CollectionUtils;
import org.springframework.util.StopWatch;

import javax.annotation.PostConstruct;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.BufferedWriter;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;


@Component
public class ExportUtil {
    private final static Logger logger = LoggerFactory.getLogger(ExportUtil.class);
    /**
     * 导出文件存储路径
     */
//    public static String defaultRootPath = System.getProperty("user.dir") + File.separator;


    /**
     * set注入配置
      */
    private static String folder;
    @Value("${download.folder:download-file}")
    public void setFolder(String folder){
        ExportUtil.folder = folder;
    }
    /**
     * 失败日志保存地址（生产环境必须使用共享盘），eg:D:\tuzhan_zhonghang_worksp\goods_media\import_error.csv
     **/
    private static String importFailLogDirectory;

    /** CSV文件列分隔符 */
    private static final String CSV_COLUMN_SEPARATOR = ",";
    /** CSV文件列分隔符 */
    private static final String CSV_RN = "\r\n";

    /**CSV文件编码*/
    private static final String CSV_CODE="gbk";

    @PostConstruct
    public void init() {
        // 共享文件夹初始化
        importFailLogDirectory = folder + File.separator + "goods_media" + File.separator;
    }

    /**
     *
     * @param fileName
     * @param headerList
     * @param filePath
     * @param dataList
     */
    public static void writeCsvFile(String fileName,List<List<Object>> headerList,String filePath, List<List<Object>> dataList) {
        writeCsvFile(fileName,headerList,filePath,dataList,false);
    }

    public static void writeCsvFile(String fileName,List<List<Object>> headerList,String filePath, List<List<Object>> dataList,boolean append){

        BufferedWriter csvWriter = null;
        File file = new File(filePath);
        try {
            csvWriter = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(file,append), StandardCharsets.UTF_8), 1024);
            //解决csv导出文件，中文乱码
            //以csv方式导出的文件中默认不含BOM信息，通过给将要输出的内容设置BOM标识(以 EF BB BF 开头的字节流)即可解决该问题
            csvWriter.write(new String(new byte[]{(byte) 0xEF, (byte) 0xBB, (byte) 0xBF}));
            for (List<Object> header : headerList) {
                writeRow(header, csvWriter);
            }
            if(CollectionUtils.isEmpty(dataList)){
                writeRow(Lists.newArrayList("未查找到符合条件的数据，请修改查询条件"),csvWriter);
            }else{
                for (List<Object> row : dataList) {
                    writeRow(row, csvWriter);
                }
            }

            csvWriter.flush();
        } catch (Exception e) {
            logger.error("生成csv文件错误=【{}】", e);
        } finally {
            try {
                if (csvWriter != null) {
                    csvWriter.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        logger.info("文件生成完成，文件名称：{}", file.getName());
    }

    public static void createCsvFile(String fileName,List<List<Object>> headerList,String rootPath, List<List<Object>> dataList){
        // 声明文件路径及名称
        if(rootPath==null){
            rootPath = importFailLogDirectory;
        }
        logger.info("导出路径=【{}】",rootPath);
        File folder = new File(rootPath);
        if(!folder.exists() && !folder.isDirectory()){
            folder.mkdirs();
        }

        File csvFile = new File(rootPath + fileName + ".csv");

        BufferedWriter csvWriter = null;
        try {
            csvWriter = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(csvFile), StandardCharsets.UTF_8), 1024);
            //解决csv导出文件，中文乱码
            //以csv方式导出的文件中默认不含BOM信息，通过给将要输出的内容设置BOM标识(以 EF BB BF 开头的字节流)即可解决该问题
            csvWriter.write(new String(new byte[]{(byte) 0xEF, (byte) 0xBB, (byte) 0xBF}));
            for (List<Object> header : headerList) {
                writeRow(header, csvWriter);
            }
            for (List<Object> row : dataList) {
                writeRow(row, csvWriter);
            }
            csvWriter.flush();
        } catch (Exception e) {
            logger.error("生成csv文件错误=【{}】", e);
        } finally {
            try {
                if (csvWriter != null) {
                    csvWriter.close();
                }
            } catch (IOException e) {
            }
        }
        logger.info("文件生成完成，文件名称：{}", csvFile.getName());
    }
    public static void createCsvFile(List<List<Object>> headerList,String fileName, List<List<Object>> dataList) {
        createCsvFile(fileName,headerList,null,dataList);
    }

    /**
     * 导出并下载
     * @param fileName
     * @param headerList
     * @param dataList
     */
    public static void exportAndDownLoadCsvFile(String fileName, List<List<Object>> headerList,
                                                List<List<Object>> dataList, HttpServletResponse response) throws IOException {
        BufferedWriter csvWriter = null;
        ServletOutputStream fileOutputStream;
        response.setContentType("application/vnd.ms-excel;charset=utf-8");
        if(fileName!=null && fileName.endsWith(".csv")){
            response.addHeader("Content-Disposition",
                    "attachment;filename=" + URLEncoder.encode(fileName, "UTF-8"));
        } else {
            response.addHeader("Content-Disposition",
                    "attachment;filename=" + URLEncoder.encode(fileName, "UTF-8") + ".csv");
        }
        fileOutputStream = response.getOutputStream();
        StopWatch stopWatch = new StopWatch();
        stopWatch.start();
        try {
            csvWriter = new BufferedWriter(new OutputStreamWriter(fileOutputStream, StandardCharsets.UTF_8), 1024);
            //解决csv导出文件，中文乱码
            //以csv方式导出的文件中默认不含BOM信息，通过给将要输出的内容设置BOM标识(以 EF BB BF 开头的字节流)即可解决该问题
            csvWriter.write(new String(new byte[]{(byte) 0xEF, (byte) 0xBB, (byte) 0xBF}));
            for (List<Object> header : headerList) {
                writeRow(header, csvWriter);
            }
            if(CollectionUtils.isEmpty(dataList)){
                writeRow(Lists.newArrayList("未查找到符合条件的数据，请修改查询条件"),csvWriter);
            }else{
                for (List<Object> row : dataList) {
                    writeRow(row, csvWriter);
                }
            }
            csvWriter.flush();
        } catch (Exception e) {
            logger.error("生成csv文件错误,文件名称：{}；错误信息：【{}】", fileName,e);
        } finally {
            try {
                if (csvWriter != null) {
                    csvWriter.close();
                }
                if (fileOutputStream != null) {
                    fileOutputStream.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        stopWatch.stop();
        logger.info("文件生成完成，文件名称：{} 耗时：{} ms", fileName,stopWatch.getTotalTimeMillis());
    }

    public static void writeRow(List<Object> row, BufferedWriter csvWriter) throws IOException {
        for (Object data : row) {
            if(data==null){
                data="";
            }
            StringBuilder sb = new StringBuilder();
            String rowStr = sb.append("\"").append(data).append("\",").toString();
            csvWriter.write(rowStr);
        }
        csvWriter.newLine();
    }



  

    public static long parseLong(String s) throws NumberFormatException {
        if(StringUtils.isBlank(s) || !StringUtils.isNumeric(s)){
            return 0L;
        }
        return Long.parseLong(s);
    }


    /**
     * 删除单个文件
     *
     * @return 单个文件删除成功返回true，否则返回false
     */
    public static boolean deleteFile( File file) {
        // 如果文件路径所对应的文件存在，并且是一个文件，则直接删除
        if (file.exists() && file.isFile()) {
            if (file.delete()) {
                return true;
            } else {
                return false;
            }
        } else {
            return false;
        }
    }


    public static byte[] exportCSV(List<List<Object>> dataList) {
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        BufferedWriter buffCvsWriter = null;
        try {
            buffCvsWriter = new BufferedWriter(new OutputStreamWriter(out, StandardCharsets.UTF_8));
            for (List<Object> row : dataList) {
                writeRow(row, buffCvsWriter);
            }
            // 刷新缓冲
            buffCvsWriter.flush();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            // 释放资源
            if (buffCvsWriter != null) {
                try {
                    buffCvsWriter.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        return out.toByteArray();
    }

    private static void fillDataToCsv(BufferedWriter buffCvsWriter, LinkedHashMap row) throws IOException {
        Map.Entry propertyEntry;
        for (Iterator<Map.Entry> propertyIterator = row.entrySet().iterator(); propertyIterator.hasNext(); ) {
            propertyEntry = propertyIterator.next();
            buffCvsWriter.write("\"" + propertyEntry.getValue().toString() + "\"");
            if (propertyIterator.hasNext()) {
                buffCvsWriter.write(",");
            }
        }
    }

    public static Object escapeNullToRod(Object o){
        if(o == null){
            return "-";
        }
        return o;
    }
    public static Object escapeNullToZero(Object o){
        if(o == null){
            return "0";
        }
        return o;
    }
}

案例： ExportUtil.writeCsvFile

    @Test
    public void CSVtest() throws IOException {

        //标题 数据头
        List<Object> titleHeader = Lists.newArrayList(new String(new byte[]{(byte) 0xEF, (byte) 0xBB, (byte) 0xBF})
                + "日期范围："
                + "2024-01-01"
                + "~"
                + "2024-06-03");
        List<List<Object>> headerList = new ArrayList<>();
        headerList.add(titleHeader);
        headerList.add(Arrays.asList("ID", "月份", "薪水"));


        //数据行
        List<List<Object>> dataList = new ArrayList<>();
        for (int i = 0; i < 3; i++) {
            ArrayList<String> values = Lists.newArrayList(i + "\t", (i + 1) + "月" + "\t", (1000 * i) + "\t");
            dataList.add(new ArrayList<>(values));
        }
        
        
        String fileName = "数据报表.csv";
        String path = "C:\\Users\\EDY\\Desktop\\fsdownload" + fileName;
        ExportUtil.writeCsvFile(fileName, headerList, path, dataList);
    }