Java IO (Java Development Chapter XII real classic study notes)

Class File 12.1 manipulate files

　　io package of documents related to the class itself is the File class.

// constructor class parameter as desired for a given file path 
public File (String pathname) {}
 // File class defines several methods and constants 
public  static  Final String pathSeparator             // constants represent the path delimiter (windows is: " ; ") 
public  static  Final String separator                 // constant path delimiter (windows are:" \ ") Linux is" / " 
public  boolean createNewFile () throws IOException   // ordinary file created 
public  boolean the delete ()                                   // delete files 
public  boolean EXISTS ()                                   //Determining whether a file exists 
public  Boolean the isDirectory ()                            // determines whether a given path is a directory of 
public  Long length ()                                       // Returns the size of the file 
public String [] List ()                                      // entire contents of which are listed in the specified directory, only the column the column names 
public file [] listFiles ()                                   // entire contents listed in the specified directory will be listed path 
public  boolean mkdir ()                                  // create a directory of 
public  boolean renameTo (file dest)                 // to rename the existing file

12.1.3 Example: list the entire contents of the specified directory

　　1. Requirements: Given a directory, listing all the contents of the directory, a given directory there may be sub-folders, requirements can be listed in all of the subfolders of subfolders.

public  static  void main (String args []) { 
  File F = new new File ( "D:" + the File.separator);   // operating path 
  Print (F); 
} 

public  static  void Print (File F) {       // called recursively The method of 
  iF (F =! null ) {
      iF (f.isDirectory ()) {                  // is a directory 
        File File [] = f.listFiles ();        // is listed 
        iF (File =! null ) {
             for ( int 0 = I; I <file.length; I ++ ) { 
               Print (File [I]);
           } 
        } 
     } The else {                                // No direct printing 
         System.out.println (F); 
     }        
  }   
}    

12.2RandomAccessFile class (the operation of the file contents)

public a RandomAccessFile (File File, String MODE) throws a FileNotFoundException       // configured to accept the object class File, designated operation path, but in the setting mode needs to be set, r is a read-only; W is a write-only; RW is read; 

public a RandomAccessFile ( name String, String MODE) throws a FileNotFoundException    // configured not use the file class object represents a file, but directly input a fixed file path 

public  void Close () throws IOException      // closing operation of 

public  int Read ( byte [] B) throws IOEception   // content to read a byte array 

public  Final  byte the readByte () throws IOEception   // read a byte 

public  Final  int the readInt () throws IOEception       // read the data from the file integer 

public  void Seek ( Long POS) throws IOEception    // set the position of the pointer 

public  Final  void writeByte (String S) throws IOEcetion     // writes a string to a file, the processing manner byte 

public  Final  void writeInt ( int V) throws IOEception    // the file data is written to an int, a length of four 

public  int skipByte ( int n- )throws IOEception // pointer to skip a specified byte

   If the file to be written does not exist, the system will automatically create