FileHelper-文件操作工具
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import java.io.File; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import javax.servlet.http.HttpServletResponse; public class FileHelper { static File file ; /** * @删除文件 * input 输入 output 输出 * */ public static boolean deleteFile(String url){ boolean flag = false; try{ if(null == file){ file = new File(url); if(file.isFile()){ if(file.canWrite()){ file.delete(); } flag = true; } }else{ if(url == file.getPath()){ file.delete(); flag = true; } } }catch(Exception e){ flag = false ; e.printStackTrace(); }finally{ file = null; System.gc(); } return flag; }
/** * 新建目录 * @param folderPath String 如 c:/fqf * @return boolean */ public static void newFolder(String folderPath) { try { String filePath = folderPath; filePath = filePath.toString(); java.io.File myFilePath = new java.io.File(filePath); if (!myFilePath.exists()) { myFilePath.mkdir(); } } catch (Exception e) { e.printStackTrace(); } }
/** * 复制单个文件 * @param oldPath String 原文件路径 如：c:/fqf.txt * @param newPath String 复制后路径 如：f:/fqf.txt * @return boolean */ public static void copyFile(String oldPath, String newPath) { try { int bytesum = 0; int byteread = 0; File oldfile = new File(oldPath); if (oldfile.exists()) { //文件存在时 InputStream inStream = new FileInputStream(oldPath); //读入原文件 FileOutputStream fs = new FileOutputStream(newPath); byte[] buffer = new byte[1444]; int length; while ( (byteread = inStream.read(buffer)) != -1) { bytesum += byteread; //字节数 文件大小 fs.write(buffer, 0, byteread); } inStream.close(); fs.close(); } } catch (Exception e) { e.printStackTrace(); } } /**
* 使用文件通道的方式复制文件 * @param s 源文件 * @param t 复制到的新文件 */ public static void fileChannelCopy(String srcPath,String outpath) { File s = new File(srcPath); File t = new File(outpath); FileInputStream fi = null; FileOutputStream fo = null; FileChannel in = null; FileChannel out = null; try { fi = new FileInputStream(s); fo = new FileOutputStream(t); in = fi.getChannel();//得到对应的文件通道 out = fo.getChannel();//得到对应的文件通道 in.transferTo(0, in.size(), out);//连接两个通道，并且从in通道读取，然后写入out通道 } catch (IOException e) { e.printStackTrace(); } finally { try { fi.close(); in.close(); fo.close(); out.close(); } catch (IOException e) { e.printStackTrace(); } } }
/** * 上传文件 * @param upFile 上传文件 * @param targetFile 目标文件 * @param b * @return */ public static boolean fileUpload(File upFile , File targetFile , byte[] b){ InputStream is = null ; OutputStream os = null ; try{ is = new FileInputStream(upFile); os= new FileOutputStream(targetFile); int length = 0; while((length = is.read(b))>0){ os.write(b, 0, length); } }catch(Exception e){ e.printStackTrace(); return false; }finally{ try { if(null != is){ is.close(); }if(null != os){ os.close(); } } catch (IOException e) { e.printStackTrace(); } } return true; } /** * 删除文件 * @param f * @return */ public static boolean deleteFile(File f){ if (f.isFile()) f.delete(); return true; }
/** * 删除文件夹 * @param f * @return */ public static boolean deleteDir(File f){ if(f.isDirectory()){ File[] files = f.listFiles(); for(int i=0;i<files.length;i++){ if(files[i].isDirectory()) deleteDir(files[i]); else deleteFile(files[i]); } } f.delete(); return true ; }
/** * 文件下载 * @param filePath 文件路径 * @param fileType 文件类型 * @param downName 下载文件名称 * @param response 响应 */ public static void downLoadFile(String filePath,String fileType ,String downName,HttpServletResponse response){ OutputStream out = null;// 创建一个输出流对象 String headerStr = downName; try{ InputStream is=new FileInputStream(filePath); out = response.getOutputStream();// headerStr =new String( headerStr.getBytes("gb2312"), "ISO8859-1" );//headerString为中文时转码 response.setHeader("Content-disposition", "attachment; filename="+ headerStr+"."+fileType);// filename是下载的xls的名，建议最好用英文 response.setContentType("application/msexcel;charset=GB2312");// 设置类型 response.setHeader("Pragma", "No-cache");// 设置头 response.setHeader("Cache-Control", "no-cache");// 设置头 response.setDateHeader("Expires", 0);// 设置日期头 // 输入流 和 输出流 int len = 0; byte[] b = new byte[1024]; while ((len = is.read(b)) != -1) { out.write(b, 0, len); } is.close(); out.flush(); out.close(); } catch (Exception e) { e.printStackTrace(); } finally { try { if (out != null) { out.close(); } } catch (IOException e) { e.printStackTrace(); } } }
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