File, InputStream, and OutputStream, Befferedinputstream, and Bufferedoutputstream three ways to copy files

1 ImportJava.io.File;2 3  Public classShowfile {4 5      Public Static voidMain (string[] args) {6 7File dir =NewFile ("E:/aaa");8         if(Dir.exists ()) {9 Ten Show (dir, dir); One}Else { ASYSTEM.OUT.PRINTLN ("This directory does not exist"); -         }         -     } the  -     /** - * Show -      *  +      * @paramfile1: - * Current object (directory or file) +      * @paramfile2: A * Root directory at      */ -      -      Public Static voidShow (file file1, file file2) { -         if(File1.isdirectory ()) { -  -file[] Files =file1.listfiles (); in  -              for(inti = 0; i < files.length; i++) { to              +Showfile SF =Newshowfile (); -                 intn =Sf.num (Files[i], file2); the                  *                  for(intj = 0; J < N; J + +) { $System.out.print ("\ t");Panax Notoginseng                 } - System.out.println (Files[i].getname ()); the                 //Recursive invocation + Show (Files[i], file2); A  the             } +         } -     } $  $     intb = 0; -      Public  intnum (file file1, file file2) { -  the         //Compare the current file and root directory -         //if File1.getparentfile () and file2 are equal, they represent folders of the same rankWuyi         if(File1.getparentfile (). Equals (File2)) { the             returnb; -}Else { Wub++; -             returnnum (File1.getparentfile (), file2); About         } $  -     } -  -}

1  Public classCopy {2      Public Static voidMain (string[] args)throwsIOException {3String Path = "E:" +file.separator+ "SDF";4     5File File =NewFile (Path, "Abc.rar" );6     7File file1 =NewFile (Path, "Cba.rar");8         9InputStream is =Newfileinputstream (file);Ten          OneOutputStream Ops =NewFileOutputStream (file1); A          -         byte[] by =New byte[20*1024]; -          the         intn = 0;  -      -          while(N=is.read (by))!=-1){ -          + Ops.write (by); - System.out.println (n); +              A         } at          -         /** - read (file file) in the *io stream, - * Reads a byte of data from this input stream. If no input is available, this method will block.  - returns: The next data byte, or 1 if the end of the file has been reached.  - read (file file) ultimately returns the total number of bytes owned by the target file being read in          */ -          to is.close (); + Ops.flush (); - ops.close (); the          *     } $ Panax Notoginseng}

1 /**2 *bufferedinputstream adds some functionality to another input stream, which is buffered input and the ability to support the mark and reset methods. 3 * When creating bufferedinputstream, an internal buffer array is created. 4 * When reading or skipping bytes in a stream, the internal buffer can be populated again from the included input stream as needed, populating multiple bytes at once. 5 The *mark operation Records a point in the input stream, and the reset action causes the new byte to be fetched from the included input stream before the6 * Read all bytes read again from the last mark operation. 7  */8  Public classbuffercopy {9      Public Static voidMain (string[] args)throwsIOException {TenString Path = "E:" +file.separator+ "SDF" +file.separator+ "Abc.rar"; One          A         //determine if the same file exists under this path -         if(!NewFile (NewFile (Path). Getparentfile (), "Sdfd.rar"). Exists ()) { -  the             //creates an output stream that reads the file data of the Files object -InputStream is =NewFileInputStream (NewFile (path)); -             //implementing the output stream that gets the data -Bufferedinputstream bis =NewBufferedinputstream (IS); +              -             //creates an output stream that writes file data to the Files object +OutputStream OS =NewFileOutputStream (NewFile (NewFile (Path)). Getparentfile (), "Sdfd.rar")); A             //implementing an output stream that writes data atBufferedoutputstream BOS =Newbufferedoutputstream (OS); -             //Create a byte[] buffer to ensure that the capacity is large enough -             byte[] by =New byte[20*1024]; -             intn = 0; -              while((n = is.read ())! = 1){ - Os.write (by); in             } -              to is.close (); + Os.flush (); - os.close (); the         } *System.out.println ("exists"); $         Panax Notoginseng     } -  the}

File, InputStream, and OutputStream, Befferedinputstream, and Bufferedoutputstream three ways to copy files