文件操作（文件过滤，压缩，导出到excel等）

文件过滤

通过实现文件名过滤器FilenameFilter，过滤指定的文件列表

//根据后缀名过滤文件列表public class FolderFilter implements FilenameFilter {    private String extensions; // 后缀名    public FolderFilter(String extensions){        this.extensions = extensions;    }    @Override    public boolean accept(File dir, String name) {        return name.endsWith(extensions);    }}//根据文件名过滤文件列表public static class ContainFolderFilter implements FilenameFilter {    private String extensions; // 后缀名    public ContainFolderFilter(String extensions){        this.extensions = extensions;    }    @Override    public boolean accept(File dir, String name) {        return -1!=name.indexOf(extensions);    }}/** * 查找文件列表 */public String[] getFileList(String dirPath,String extensions){    File  file = new File(dirPath);    String[] fileNameList={};    if(file.exists()) {        fileNameList=file.list(new FolderFilter(extensions));    }    return fileNameList;}/** * 对文件列表按照指定方式排序，并返回文件名 */public String getLastestFile(String dirPath,String extensions){    File  file = new File(dirPath);    String retName="";    if(file.exists()) {        String[] fileNameList=file.list(new FolderFilter(extensions));        if(null!=fileNameList&&fileNameList.length>0){            Arrays.sort(fileNameList, new Comparator<String>() {                @Override                public int compare(String o1, String o2) {                    String filedate=o1.substring(o1.lastIndexOf("_")+1);                    filedate=filedate.substring(0, filedate.indexOf("."));                    int i = Integer.parseInt(String.valueOf(filedate));                    filedate=o2.substring(o2.lastIndexOf("_")+1);                    filedate=filedate.substring(0, filedate.indexOf("."));                    int j = Integer.parseInt(String.valueOf(filedate));                    if (i < j) return 1;                    if (i > j) return -1;                    return 0;                }            });            retName=fileNameList[0];        }    }    return retName;}

压缩与解压缩

/** * 功能:压缩多个文件成一个zip文件 * @param fileNameArray：源文件名列表 * @param zipName：压缩后的文件名 */public void zipFiles(String dirPath,String filePath,String[] fileNameArray, String zipName) throws Exception {    File[] fileArray=new File[fileNameArray.length];    for(int i=0;i<fileArray.length;i++){        File zipfile = new File("D:\\xlsx"+File.separator+fileNameArray[i]);        if(zipfile.exists()){            fileArray[i]=zipfile;        }    }    if(!new File(dirPath).exists()){        new File(dirPath).mkdirs();    }    File zipfile = new File(filePath);    zipFiles(fileArray,zipfile);}/** * 功能:压缩多个文件成一个zip文件 * @param fileArray：源文件列表 * @param zipfile：压缩后的文件 */public void zipFiles(File[] fileArray, File zipfile) throws Exception {    byte[] buf = new byte[2048];    if(zipfile.exists()){        Boolean isDelete=zipfile.delete();        if(!isDelete){            throw new Exception("未成功删除文件，请关闭使用该文件的所有进程或者流！！");        }    }    //ZipOutputStream类：完成文件或文件夹的压缩    ZipOutputStream out = new ZipOutputStream(new FileOutputStream(zipfile));    FileInputStream in=null;    try{        for (int i = 0; i < fileArray.length; i++) {            in = new FileInputStream(fileArray[i]);            out.putNextEntry(new ZipEntry(fileArray[i].getName()));            int len;            while ((len = in.read(buf)) > 0) {                out.write(buf, 0, len);            }            out.closeEntry();            in.close();        }    }catch (Exception e) {        e.printStackTrace();    }finally {        if(null!=in){            in.close();        }        out.close();    }}/** * 功能:解压缩 * @param zipfile：需要解压缩的文件 * @param descDir：解压后的目标目录 */public void unZipFiles(File zipfile, String descDir) {    InputStream in=null;    OutputStream out=null;    ZipFile zf =null;    try {        zf=new ZipFile(zipfile);        for (Enumeration entries = zf.entries(); entries.hasMoreElements();) {            ZipEntry entry = (ZipEntry) entries.nextElement();            String zipEntryName = entry.getName();            in = zf.getInputStream(entry);            out = new FileOutputStream(descDir + zipEntryName);            byte[] buf1 = new byte[1024];            int len;            while ((len = in.read(buf1)) > 0) {                out.write(buf1, 0, len);            }        }    } catch (Exception e) {        e.printStackTrace();    } finally {        if(null!=in){            try {                in.close();            } catch (IOException e) {                e.printStackTrace();            }        }        if(null!=out){            try {                out.close();            } catch (IOException e) {                e.printStackTrace();            }        }        if(null!=zf){            try {                zf.close();            } catch (IOException e) {                e.printStackTrace();            }        }    }}

文件转化成byte[]

/** * 文件转byte数组 * * @param filename * @return * @throws IOException */public static byte[] fileToByteArray(String dirPath,String filename) throws IOException {    File file = new File(dirPath+ File.separator +filename);    if (!file.exists()) {        throw new FileNotFoundException(filename);    }    ByteArrayOutputStream bos = new ByteArrayOutputStream((int) file.length());    BufferedInputStream in = null;    try {        in = new BufferedInputStream(new FileInputStream(file));        int buf_size = 2048;        byte[] buffer = new byte[buf_size]; //buff用于存放循环读取的临时数据        int len = 0;        while (-1 != (len = in.read(buffer, 0, buf_size))) {            bos.write(buffer, 0, len);        }        return bos.toByteArray();//转换之后的结果    } catch (IOException e) {        e.printStackTrace();        throw e;    } finally {        if(null!=in){            try {                in.close();            } catch (IOException e) {                e.printStackTrace();            }        }        bos.close();    }}

excel

maven配置

<dependency>    <groupId>org.apache.poi</groupId>    <artifactId>poi</artifactId>    <version>3.9</version></dependency><dependency>    <groupId>org.apache.poi</groupId>    <artifactId>poi-ooxml</artifactId>    <version>3.9</version></dependency>

/** * * @param title         sheet名 * @param headers       sheet标题 * @param dataset       要写入的数据，传入普通的java bean集合 * @param outStream     文件输出流，此参数决定了文件名及文件存储路径 * @param dataPattern   日期格式    yyyy-MM-dd-HH-mm-ss * @return Map          code 0成功-1失败  mes 相关信息 */public Map<String, Object> exportExcel(String title, String[] headers, Collection<T> dataset,InputStream inputStream, OutputStream outStream, String dataPattern,Boolean is2003Excel) {    //  返回值map    Map<String, Object> retMap = new HashMap<String, Object>();    // 声明一个工作薄    Workbook workbook = null;        //ByteArrayOutputStream byteOutStream=new ByteArrayOutputStream();    try {        if (is2003Excel) {            workbook = new HSSFWorkbook(inputStream);        } else {            workbook = new XSSFWorkbook(inputStream);        }    }  catch (IOException e) {        e.printStackTrace();        if (is2003Excel) {            workbook = new HSSFWorkbook();        } else {            // 这里1000是在内存中的数量，如果大于此数量时，会写到硬盘，以避免在内存导致内存溢出               //new SXSSFWorkbook(1000);              workbook = new XSSFWorkbook();        }    }    try {        /*        //sheetNum 第n个sheet         //MAXROW 每个表单最大允许行数        int leng=MAXROW;        for(int sheetNum=0;sheetNum<=size/MAXROW;sheetNum++){             Sheet sheet = workbook.createSheet(title+"-"+sheetNum);            //list中第num条数据            for(;num<=leng&&num<=size;num++){            }            leng+=MAXROW;        }        */        // 生成一个表格        Sheet sheet = workbook.createSheet(title);        // 生成一个样式        CellStyle style = workbook.createCellStyle();        // 设置这些样式        style.setFillForegroundColor(HSSFColor.SKY_BLUE.index);        style.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND);        style.setBorderBottom(HSSFCellStyle.BORDER_THIN);        style.setBorderLeft(HSSFCellStyle.BORDER_THIN);        style.setBorderRight(HSSFCellStyle.BORDER_THIN);        style.setBorderTop(HSSFCellStyle.BORDER_THIN);        style.setAlignment(HSSFCellStyle.ALIGN_CENTER);        // 生成一个字体        Font font = workbook.createFont();        font.setColor(HSSFColor.VIOLET.index);        font.setFontHeightInPoints((short) 12);        font.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);        // 把字体应用到当前的样式        style.setFont(font);        // 生成并设置另一个样式        CellStyle style2 = workbook.createCellStyle();        style2.setFillForegroundColor(HSSFColor.LIGHT_YELLOW.index);        style2.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND);        style2.setBorderBottom(HSSFCellStyle.BORDER_THIN);        style2.setBorderLeft(HSSFCellStyle.BORDER_THIN);        style2.setBorderRight(HSSFCellStyle.BORDER_THIN);        style2.setBorderTop(HSSFCellStyle.BORDER_THIN);        style2.setAlignment(HSSFCellStyle.ALIGN_CENTER);        style2.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);        // 生成另一个字体        Font font2 = workbook.createFont();        font2.setBoldweight(HSSFFont.BOLDWEIGHT_NORMAL);        // 把字体应用到当前的样式        style2.setFont(font2);//            // 声明一个画图的顶级管理器//            HSSFPatriarch patriarch = sheet.createDrawingPatriarch();        // 定义注释的大小和位置,详见文档//            HSSFComment comment = patriarch.createComment(new HSSFClientAnchor(0, 0, 0, 0, (short) 4, 2, (short) 6, 5));        // 设置注释内容//            comment.setString(new HSSFRichTextString("可以添加注释！"));        // 设置注释作者，当鼠标移动到单元格上是可以在状态栏中看到该内容.        //comment.setAuthor("科印");        // 产生表格标题行        Row row = sheet.createRow(0);        for (int i = 0; i < headers.length; i++) {            Cell cell = row.createCell(i);            cell.setCellStyle(style);            RichTextString text=null;            if (is2003Excel) {                text = new HSSFRichTextString(headers[i]);            } else {                text = new XSSFRichTextString(headers[i]);            }            cell.setCellValue(text);        }        // 遍历集合数据，产生数据行        Iterator<T> it = dataset.iterator();        int index = 0;        while (it.hasNext()) {//                int firstImgNo = imgNo;            index++;            row = sheet.createRow(index);            Object t = (T) it.next();            // 利用反射，根据javabean属性的先后顺序，动态调用getXxx()方法得到属性值            Field[] fields = t.getClass().getDeclaredFields();            for (int i = 0; i < fields.length; i++) {                Cell cell = row.createCell(i);                cell.setCellStyle(style2);                Field field = fields[i];                String fieldName = field.getName();                String getMethodName = "get" + fieldName.substring(0, 1).toUpperCase() + fieldName.substring(1);                Class<? extends Object> tCls = t.getClass();                Method getMethod = tCls.getMethod(getMethodName, new Class[] {});                Object value = getMethod.invoke(t, new Object[] {});                // 判断值的类型后进行强制类型转换                String textValue = "";                if (value != null) {                    if (value instanceof byte[]) {                        // 有图片时，设置行高为80px;                        row.setHeightInPoints(80);                        // 设置图片所在列宽度为100px,注意这里单位的一个换算                        //sheet.setColumnWidth(i, (short) (35.7 * 100));                        sheet.setColumnWidth(i, 30 * 256);                        // sheet.autoSizeColumn(i);                        byte[] bsValue = (byte[]) value;//                            HSSFClientAnchor anchor = new HSSFClientAnchor(0, 0, 1023, 255, (short) (firstImgNo),index, (short) (firstImgNo), index);//                            anchor.setAnchorType(2);//                            patriarch.createPicture(anchor,workbook.addPicture(bsValue, HSSFWorkbook.PICTURE_TYPE_JPEG));firstImgNo++;                    } else if (value instanceof Date) {                        Date date = (Date) value;                        SimpleDateFormat sdf = new SimpleDateFormat(dataPattern);                        textValue = sdf.format(date);                    } else {                        // 其它数据类型都当作字符串                        textValue = value.toString();                    }                }                if (textValue != null && !textValue.trim().equals("")) {                    int length = textValue.getBytes().length;                    int setLength = length * 256;                    if (setLength > 65280) {                        setLength = 65280;                    }                    sheet.setColumnWidth(i, setLength);                    cell.setCellValue(textValue);                } else {                    sheet.setColumnWidth(i, 30 * 256);                    cell.setCellValue("");                }            }        }        workbook.write(outStream);        retMap.put("code",0);        retMap.put("mes","excel写入完成");        //retMap.put("data",byteOutStream.toByteArray());    }catch (Exception e){        retMap.put("code",-1);        retMap.put("mes","excel写入失败："+e.getMessage());    }finally {        try {            if(inputStream!=null){                inputStream.close();            }            if(outStream != null){                outStream.flush();                outStream.close();            }        }catch (Exception e){            retMap.put("code",-1);            retMap.put("mes","excel写入失败："+e.getMessage());        }    }    return retMap;}// 是否是2003的excel，返回true是2003public static boolean is2003Excel(String filePath) {    return filePath.matches("^.+\\.(?i)(xls)$");}// 是否是2007的excel，返回true是2007public static boolean is2007Excel(String filePath) {    //^ 表示以...开头    //. 匹配除换行符 \n 之外的任何单字符    //+ 匹配前面的子表达式一次或多次    //根据 Java Language Specification 的要求，Java 源代码的字符串中的反斜线被解释为 Unicode 转义或其他字符转义。因此必须在字符串字面值中使用两个反斜线，表示正则表达式受到保护，不被 Java 字节码编译器解释。    //(?i)即匹配时不区分大小写    //$匹配输入字符串的结尾位置    return filePath.matches("^.+\\.(?i)(xlsx)$");}