TŘÍDA JAVA.IO.FILTEROUTPUTSTREAM V JAVĚ

Třída FilterInputStream a FilterOutputStream

Java.io.FilterOutputStream class je nadtřídou všech těchto tříd, které filtruje výstupní proudy. Metoda write() třídy FilterOutputStream filtruje data a zapisuje je do základního filtrování toku, což se provádí v závislosti na tocích.

Prohlášení:

public class FilterOutputStream extends OutputStream

Konstruktéři:

FilterOutputStream(OutputStream geekout) : Vytvoří filtr výstupního proudu.

Metody:

Syntaxe:

public void write(int arg)   Parameters :    arg : Source Bytes   Return :   void   Exception :    In case any I/O error occurs.

Implementace: Java

    // Java program illustrating the working of work(int arg)   // method   import     java.io.*  ;   import     java.lang.*  ;   public     class   NewClass   {      public     static     void     main  (  String  []     args  )     throws     IOException      {      // OutputStream FileInputStream & FilterOutputStream      // initially null      OutputStream     geek_out     =     null  ;      FilterOutputStream     geek_filter     =     null  ;      // FileInputStream used here      FileInputStream     geekinput     =     null  ;      char     c  ;      int     a  ;      try      {      // create output streams      geek_out     =     new     FileOutputStream  (  'GEEKS.txt'  );      geek_filter     =     new     FilterOutputStream  (  geek_out  );      // write(int arg) : Used to write 'M' in the file      // - 'ABC.txt'      geek_filter  .  write  (  77  );      // Flushes the Output Stream      geek_filter  .  flush  ();      // Creating Input Stream      geekinput     =     new     FileInputStream  (  'GEEKS.txt'  );      // read() method of FileInputStream :      // reading the bytes and converting next bytes to int      a     =     geekinput  .  read  ();      /* Since read() converts bytes to int so we    convert int to char for our program output*/      c     =     (  char  )  a  ;      // print character      System  .  out  .  println  (  'Character written by'     +      ' FilterOutputStream : '     +     c  );      }      catch  (  IOException     except  )      {      // if any I/O error occurs      System  .  out  .  print  (  'Write Not working properly'  );      }      finally  {      // releases any system resources associated with      // the stream      if     (  geek_out     !=     null  )      geek_out  .  close  ();      if     (  geek_filter     !=     null  )      geek_filter  .  close  ();      }      }   }

GEEKS.txt

výstup:

Character written by FilterOutputStream : M

'arg.length'

Syntaxe:

public void write(byte[] arg)   Parameters :    buffer : Source Buffer to be written to the Output Stream   Return :   void   Exception :    In case any I/O error occurs.

Implementace: Java

    // Java program illustrating the working of work(byte   // buffer) method   import     java.io.*  ;   import     java.lang.*  ;   public     class   NewClass   {      public     static     void     main  (  String  []     args  )     throws     IOException      {      // OutputStream FileInputStream & FilterOutputStream      // initially null      OutputStream     geek_out     =     null  ;      FilterOutputStream     geek_filter     =     null  ;      // FileInputStream used here      FileInputStream     geekinput     =     null  ;      byte  []     buffer     =     {  77       79       72       73       84  };      char     c  ;      int     a  ;      try      {      // create output streams      geek_out     =     new     FileOutputStream  (  'ABC.txt'  );      geek_filter     =     new     FilterOutputStream  (  geek_out  );      // writes buffer to the output stream      geek_filter  .  write  (  buffer  );      // forces byte contents to written out to the stream      geek_filter  .  flush  ();      // create input streams      geekinput     =     new     FileInputStream  (  'ABC.txt'  );      while     ((  a  =  geekinput  .  read  ())  !=-  1  )      {      // converts integer to the character      c     =     (  char  )  a  ;      // prints      System  .  out  .  print  (  c  );      }      }      catch  (  IOException     except  )      {      // if any I/O error occurs      System  .  out  .  print  (  'Write Not working properly'  );      }      finally      {      // releases any system resources associated      // with the stream      if     (  geek_out     !=     null  )      geek_out  .  close  ();      if     (  geek_filter     !=     null  )      geek_filter  .  close  ();      }      }   }

GEEKS.txt

výstup:

MOHIT

write(byte[] buffer int offset int maxlen) : java.io.FilterOutputStream.write(byte[] buffer int offset int maxlen) zapíše maxlen bajtů ze zadané vyrovnávací paměti počínaje offsetovou pozicí do výstupního proudu.

Syntaxe:

public void write(write(byte[] buffer int offset int maxlen)   Parameters :    buffer : Source Buffer to be written to the Output Stream   Return :   buffer : Source Buffer to be written offset : Starting offset maxlen : max no. of bytes to be written to the Output Stream   Exception :    In case any I/O error occurs.

Syntaxe:

public void flush()   Parameters :    ------   Return :   void   Exception :    In case any I/O error occurs.

Syntaxe:

public void close()   Parameters :    ------   Return :   void   Exception :    In case any I/O error occurs.

Java program ilustrující: write(byte[] buffer int offset int maxlen) flush() close() metody

Java

    // Java program illustrating the working of   // write(byte[] buffer int offset int maxlen)   // flush() close() method   import     java.io.*  ;   import     java.lang.*  ;   public     class   NewClass   {      public     static     void     main  (  String  []     args  )     throws     IOException      {      // OutputStream FileInputStream & FilterOutputStream      // initially null      OutputStream     geek_out     =     null  ;      FilterOutputStream     geek_filter     =     null  ;      // FileInputStream used here      FileInputStream     geekinput     =     null  ;      byte  []     buffer     =     {  65       66       77       79       72       73       84  };      char     c  ;      int     a  ;      try      {      // create output streams      geek_out     =     new     FileOutputStream  (  'ABC.txt'  );      geek_filter     =     new     FilterOutputStream  (  geek_out  );      // write(byte[] buffer int offset int maxlen) :      // writes buffer to the output stream      // Here offset = 2 so it won't read first two bytes      // then maxlen = 5 so it will print max of 5 characters      geek_filter  .  write  (  buffer       2       5  );      // forces byte contents to written out to the stream      geek_filter  .  flush  ();      // create input streams      geekinput     =     new     FileInputStream  (  'ABC.txt'  );      while     ((  a     =     geekinput  .  read  ())  !=-  1  )      {      // converts integer to the character      c     =     (  char  )  a  ;      // prints      System  .  out  .  print  (  c  );      }      }      catch  (  IOException     except  )      {      // if any I/O error occurs      System  .  out  .  print  (  'Write Not working properly'  );      }      finally      {      // releases any system resources associated      // with the stream      if     (  geek_out     !=     null  )      geek_out  .  close  ();      if     (  geek_filter     !=     null  )      geek_filter  .  close  ();      }      }   }