CVS文件生成下载

Dear 丶 2024-04-01 14:36 105阅读 0赞

@Service  
public class ReportExportUtil \{

/**
     * 生成CVS文件
     *
     * @param dataset 源数据集合
     * @param map        csv文件的列表头map
     * @param fileName   文件名称
     * @return
     * @throws IOException
     * @throws NoSuchMethodException
     * @throws InvocationTargetException
     */
    public static <T> void createCSVFile(Collection<T> dataset, LinkedHashMap map, String fileName,HttpServletResponse response)
            throws IOException, InvocationTargetException, NoSuchMethodException {
        BufferedWriter bufferedWriter = null;
        File csvFile = null;
        // 定义文件名格式并创建
        try {
            csvFile = File.createTempFile(fileName, ".csv");
            bufferedWriter = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(csvFile), "UTF-8"),
                    1024);
            // 写入头部
            for (Iterator headIterator = map.entrySet().iterator(); headIterator.hasNext(); ) {
                Map.Entry headEntry = (Map.Entry) headIterator.next();
                bufferedWriter.write((String) headEntry.getValue() != null ? (String) headEntry.getValue() : "");
                if (headIterator.hasNext()) {
                    bufferedWriter.write(",");
                }
            }
            bufferedWriter.newLine();
            Iterator<T> it = dataset.iterator();
            while (it.hasNext()) {
                T t = (T) it.next();
                // 获取类属性
                Field[] fields = t.getClass().getDeclaredFields();
                String[] csvContent = new String[fields.length];
                for (short i = 0; i < fields.length; i++) {
                    Field field = fields[i];
                    String fieldName = field.getName();
                    String fieldType = field.getType().toString();
                    if ( !isContains(fieldName)&&i == fields.length - 1) {
                        bufferedWriter.newLine();
                    }
                    if (!isContains(fieldName)) {
                        continue;
                    }
    
                    String getMethodName = "get" + fieldName.substring(0, 1).toUpperCase() + fieldName.substring(1);
                    try {
                        Class tCls = t.getClass();
                        Method getMethod = tCls.getMethod(getMethodName, new Class[]{});
                        Object value = getMethod.invoke(t, new Object[]{});
                        // 取值并赋给数组
                        String textvalue = null;
                        if (value==null){
                            textvalue = " ";
                        }else{
                            if (fieldType.equals("class java.util.Date")) {
                                SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd");
                                textvalue = sdf.format(value);
                            }else{
                                textvalue = value.toString();
                            }
                        }
                        bufferedWriter.write(textvalue);
                        if (i < fields.length - 1) {
                            bufferedWriter.write(",");
                        }
                        if (i == fields.length - 1) {
                            bufferedWriter.newLine();
                        }
                    } catch (Exception e) {
                        e.getStackTrace();
                    }
                }
                bufferedWriter.flush();
            }
        } finally {
            bufferedWriter.close();
        }
    
        byte[] b = new byte[1024];
        File fileLoad = new File(csvFile.getCanonicalPath());
        response.reset();
        response.setContentType("application/csv");
        String trueCSVName="PaymentReport_" + DateUtils.getCurrentDateTime() + ".csv";
        trueCSVName = new String(trueCSVName.getBytes("GBK"), "ISO8859-1");
        response.setHeader("Content-Disposition", "attachment; filename=" + trueCSVName);
        FileInputStream in = new FileInputStream(fileLoad);
        int len = 0;
        byte[] buffer = new byte[1024];
        response.setCharacterEncoding("UTF-8");
        OutputStream out = response.getOutputStream();
        while ((len = in.read(buffer)) > 0) {
            out.write(new byte[]{(byte) 0xEF, (byte) 0xBB, (byte) 0xBF});
            out.write(buffer, 0, len);
        }
        in.close();
        csvFile.delete();
    
    }
    
    /**
     * 下载文件
     *
     * @param response
     * @param csvFilePath 文件路径
     * @param fileName    文件名称
     */
    public static void exportFile(HttpServletResponse response, String csvFilePath, String fileName) {
        response.setContentType("application/csv;charset=UTF-8");
        InputStream in = null;
        try {
            response.setHeader("Content-Disposition", "attachment; filename=" + URLEncoder.encode(fileName, "UTF-8"));
            in = new FileInputStream(csvFilePath+fileName);
            int len = 0;
            byte[] buffer = new byte[1024];
            response.setCharacterEncoding("UTF-8");
            OutputStream out = response.getOutputStream();
            while ((len = in.read(buffer)) > 0) {
                out.write(new byte[]{(byte) 0xEF, (byte) 0xBB, (byte) 0xBF});
                out.write(buffer, 0, len);
            }
            in.close();
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            if (in != null) {
                try {
                    in.close();
                } catch (IOException e) {
                    throw new RuntimeException();
                }
            }
        }
    }
    
    
    public static LinkedHashMap<String,String> getreportHeaders(){
        LinkedHashMap map = new LinkedHashMap();
        map.put("1", "日期");
        map.put("2", "通证编号");
        map.put("3", "签发日期");
        map.put("4", "持证方");
        map.put("5", "到期悦票金额");
        return map;
    }
    
    /**
     * 判断是否是报表字段
     * @param field
     * @return
     */
    public static boolean isContains(String field){
        Set reportFields = new HashSet(Arrays.asList("expireDate", "tokenNo","issueDate","toCorpName","amount"));
        if (reportFields.contains(field)) {
            return true;
        }else{
            return false;
        }
    }