java隐藏文件的读写（Java hides the read and write of files）.docVIP

java隐藏文件的读写（Java hides the read and write of files） Java read and write hidden files Java read and write hidden files and common file is slightly different, as follows: If you use the: FileOutputStream out = new FileOutputStream (file); You will get an error: access denied Java.io.FileNotFoundException: **.txt (access denied. ) At java.io.FileOutputStream.open (Native Method) Even if we set the write permissions as well. You can see the open Java call the local method, So we can not call the open method to call the openAppend method is added: So we can use the new FileOutputStream (file, true) to write, but can only be written, and cannot modify operation. Publicvoid appendDatatoHiddenFile (String file) { {try FileOutputStream out = new FileOutputStream (file, true); PrintStream P = new PrintStream (out); For (int i = 0; I 10; i++) P.println (hello: + I); Catch (FileNotFoundException E) {} (e.printStackTrace); } } So how to operate any hidden files? The use of RandomAccessFile A brief introduction to the RandomAccessFile: The input and output streams flow FileInputStream FileOutputStream, the realization of the disk file sequential read and write, and read and write to create different objects. Compared with the RandomAccessFile class file may be on the realization of the random read and write operations. If a file is 30 bytes, read data, read from 20-30, skip () / skip method. The RandomAccessFile class, which can serve as input may be used as the output stream. Can be seen as the node flow. The location of the file pointer RandomAccessFile object according to the following rules; at the beginning of the new RandomAccessFile object file pointer to a location in the document; after each write operation, the corresponding file pointer position after the shift to the number of bytes read and write; you can get the location of the file pointer position through the getFilePointer method to set the file pointer by seek method position. RandomAccessFile commonly used met