创建csv文件写入数据

直接上代码

package com.paasit.pai.core.utils;

import org.apache.commons.lang.StringUtils;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.*;
import java.net.URLEncoder;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;

/**
 * @description: 创建csv文件写入数据，并返回文件
 * @Author: San Zhang
 * @Date: 2023-03-02 13:31
 */
public class OSSCSVUtils {
    /**
     * 功能说明：获取UTF-8编码文本文件开头的BOM签名。
     * BOM(Byte Order Mark)，是UTF编码方案里用于标识编码的标准标记。例：接收者收到以EF BB BF开头的字节流，就知道是UTF-8编码。
     *
     * @return UTF-8编码文本文件开头的BOM签名
     */
    public static String getBOM() {
        byte b[] = {(byte) 0xEF, (byte) 0xBB, (byte) 0xBF};
        return new String(b);
    }

    /**
     * 生成CVS文件
     *
     * @param exportData 源数据List
     * @param map        csv文件的列表头map
     * @param outPutPath 文件路径
     * @return
     */
    @SuppressWarnings("rawtypes")
    public static File createCSVFile(List exportData, LinkedHashMap map, String outPutPath) {
        File csvFile = null;
        BufferedWriter csvFileOutputStream = null;
        try {
            File file = new File(outPutPath);
            if (!file.exists()) {
                file.mkdirs();
            }
            //定义文件名格式并创建
            csvFile = new File(outPutPath);
            file.createNewFile();
            // UTF-8使正确读取分隔符","
            //如果生产文件乱码，windows下用gbk，linux用UTF-8
            csvFileOutputStream = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(
                csvFile), "UTF-8"), 1024);

            //写入前段字节流，防止乱码
            csvFileOutputStream.write(getBOM());
            // 写入文件头部
            for (Iterator propertyIterator = map.entrySet().iterator(); propertyIterator.hasNext(); ) {
                java.util.Map.Entry propertyEntry = (java.util.Map.Entry) propertyIterator.next();
                csvFileOutputStream.write((String) propertyEntry.getValue() != null ? (String) propertyEntry.getValue() : "");
                if (propertyIterator.hasNext()) {
                    csvFileOutputStream.write(",");
                }
            }
            csvFileOutputStream.newLine();
            // 写入文件内容
            for (Iterator iterator = exportData.iterator(); iterator.hasNext(); ) {
                Object row = (Object) iterator.next();
                for (Iterator propertyIterator = map.entrySet().iterator(); propertyIterator
                    .hasNext(); ) {
                    java.util.Map.Entry propertyEntry = (java.util.Map.Entry) propertyIterator
                        .next();
                    String str = row != null ? ((String) ((Map) row).get(propertyEntry.getKey())) : "";

                    if (StringUtils.isEmpty(str)) {
                        str = "";
                    } else {
                    // 处理特殊字符防止生成的文件数据错位
                        str = str.replaceAll("\"", "\"\"");
                        str = str.replaceAll("”", "\"\"");
                        str = str.replaceAll("\n", "\\\\n");
                        str = str.replaceAll("\r", "\\\\r");
                        if (str.indexOf(",") >= 0) {
                            str = "\"" + str + "\"";
                        } else if (str.indexOf("，") >= 0) {
                            str = "\"" + str + "\"";
                        }
                    }
                    csvFileOutputStream.write(str);
                    if (propertyIterator.hasNext()) {
                        csvFileOutputStream.write(",");
                    }
                }
                if (iterator.hasNext()) {
                    csvFileOutputStream.newLine();
                }
            }
            csvFileOutputStream.flush();
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            try {
                csvFileOutputStream.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return csvFile;
    }

    public static void exportFile(HttpServletResponse response, String csvFilePath, String fileName) throws IOException {
        response.setContentType("application/csv;charset=UTF-8");
        response.setHeader("Content-Disposition", "attachment; filename=" +
            URLEncoder.encode(fileName, "UTF-8"));

        InputStream in = null;
        try {
            in = new FileInputStream(csvFilePath);
            int len = 0;
            byte[] buffer = new byte[1024];
            response.setCharacterEncoding("UTF-8");
            ServletOutputStream servletOutputStream = response.getOutputStream();
            while ((len = in.read(buffer)) > 0) {
                servletOutputStream.write(new byte[]{-17, -69, -65});
                servletOutputStream.write(buffer, 0, len);
            }
        } catch (FileNotFoundException e) {
            System.out.println(e);
        } finally {
            if (in != null) {
                try {
                    in.close();
                } catch (Exception e) {
                    throw new RuntimeException(e);
                }
            }
        }
    }

    public static void deleteFiles(String filePath) {
        File file = new File(filePath);
        if (file.exists()) {
            File[] files = file.listFiles();
            for (int i = 0; i < files.length; i++) {
                if (files[i].isFile()) {
                    files[i].delete();
                }
            }
        }
    }

    public static void deleteFile(String filePath, String fileName) {
        File file = new File(filePath);
        if (file.exists()) {
            File[] files = file.listFiles();
            for (int i = 0; i < files.length; i++) {
                if (files[i].isFile() &&
                    files[i].getName().equals(fileName)) {
                    files[i].delete();
                    return;
                }
            }
        }
    }
}