java io ioexception

After a day of study, the basic has a certain understanding of Java--io, and now share with you.Java. The IO package defines the types of multiple streams (classes or abstract classes) to implement input and output functions, which can be categorized from different angles:Can be divided into input stream and output stream according to different direction of data

The BufferedReader described in http://my.oschina.net/u/2263278/blog/508770 refers to one of its characteristics----when BufferedReader reads data from the input stream, if no valid data is read , where the program will block execution of the thread (using the Read () method of InputStream to fetch data from the stream, it will block the thread if there is no data in the data source), that is, the input stream described earlier, the output stream is blocked input, output. The traditional input a

to garbled; character streams are read by character and are typically used to read Chinese 3.) based on the Read method: node stream and cache stream three, BYTE stream Java.io.InputStream Java,io,outputstream1.fileinputstream class① the stream inherits from the InputStream used to read data from a file, its objects can be created with the keyword new.② Construction MethodYou can use the file name of a str

1, read/write (input/output) is for me, not for you to manipulate the object, such as reading the file is I read the file, for me is input, and I write files, for me is the output.2, Java IO uses the packaging mode, a flow wrapper another stream, to achieve better purposes. What is the rule of a flow wrapper for another flow? Use the byte stream to read the file, FileInputStream (new file ()), which you can

a general concept of performance optimization It is generally believed that Java programs are always slower than C programs, and most people may have heard too much about this kind of advice. In fact, the situation is far more complicated than the old claims. Many Java programs are really slow, but slow speed is not an intrinsic feature of all Java programs. Many

());}}// Copy a fileElse {This. copyfile (source, DEST );}}// Delete files and foldersPublic void deletefield (string source ){File sourcefile = new file (source );// FolderIf (sourcefile. isdirectory ()){String [] names = sourcefile. List ();// Delete the subfiles and subfolders in the current folderFor (string name: names ){Deletefield (source + "/" + name );}// Delete the current folderSourcefile. Delete ();}// FileElse {Sourcefile. Delete ();}}// Cut the file and folderPublic void cutfield

Three classification methods of one Io stream:1. Score by Flow Direction: Input stream: Only bytes of data can be read from it, and data cannot be written to itOutput stream: Only bytes of data can be written to and cannot be read from. 2. Data Types processed by the stream can be divided: Byte stream: used to process byte data. Bytes stream: used to process UNICODE character data. 3. The format can be divided: Node stream (low-level stream): it can

=New A3 ();The path of the Cat.png picture in the computer D drive String filePath1 ="D:/cat.png";The path to the Cat.png picture in the E-drive of the computer String filePath2 ="E:/cat.png";Copy file A2.copyfile (filePath1, filePath2); }/** * File Copy *@param filepath_old: The path of the file to be copied *@param filepath_new: The path where the files are copied */PublicvoidCopyFile(String filepath_old, String filepath_new) {FileInputStream fis=null; FileOutputStream Fout =null;try {Instant

Original address: http://tutorials.jenkov.com/java-nio/nio-vs-io.htmlauthor : Jakob Jenkov translator : Guo proofreading: Fang FeiAfter learning the APIs for Java NIO and Io, a problem immediately poured into my mind:When should I use IO and when do I use NIO? In this article, I'll try to clearly parse the differences

();/* Registers the Selector on the server socket and sets the notification to accept the acceptance method.This tells selector that the socket wants to be placed in the ready table when the accept operation occursSo that multiple non-blocking I/O is allowed to occur. */Selectionkey Acceptkey = Ssc.register (Acceptselector,Selectionkey.op_accept);int keysadded = 0;The/*select method returns when any of the above-registered operations occur */while ((keysadded = Acceptselector.select ()) > 0) {A

(FileNotFoundException e) {e.printstacktrace (); } Catch(IOException e) {//TODO auto-generated Catch blockE.printstacktrace (); } }}Results:Please enter what you want to write to the file: Enter E to finish your study, and keep up Hello java! end of file write !Test.txtABCDEFG Good study, Day day upWhen writing, if the file does not exist, the file will be created automatically, if it is not test