Методы класса Java.io.OutputStreamWriter

Опубликовано: 15 Февраля, 2022


Класс OutputStreamWriter соединяет символьные потоки с байтовыми потоками. Он кодирует символы в байты с использованием указанной кодировки.
Декларация:

 открытый класс OutputStreamWriter
   расширяет Writer

Конструкторы:

  • OutputStreamWriter (OutputStream geek_out): создает «geek_out» OutputStreamWriter, который использует
    кодировка по умолчанию для кодирования.
  • OutputStreamWriter (OutputStream geek_out, Charset geek_set): создает «geek_out» OutputStreamWriter, который использует кодировку «geek_set» для кодирования.
  • OutputStreamWriter (OutputStream geek_out, CharsetEncoder encode): создает «geek_out» OutputStreamWriter, который использует данный кодировщик.
  • OutputStreamWriter (OutputStream geek_out, String setName): создает «geek_out» OutputStreamWriter, который использует именованный набор символов.

Methods:

  • flush() : java.io.OutputStreamWriter.flush() flushes the stream.
    Syntax :
    public void flush()
    Parameters : 
    ------
    Return : 
    void
    Exception : 
    -> IOException : if in case anu I/O error occurs.
    
  • close() : java.io.OutputStreamWriter.close() closes the flushed stream.
    Syntax :

    public void close()
    Parameters : 
    ------
    Return : 
    void
    Exception : 
    -> IOException : if in case anu I/O error occurs, e.g writing after closing the sream
    
  • write(int char) : java.io.OutputStreamWriter.write(int char) writes a single character.
    Syntax :
    public void write(int char)
    Parameters : 
    char : character to be written
    Return : 
    void
    
    // Java code explaining the working of write(int char), flush(), close()
      
    import java.io.*;
    public class NewClass
    {
        public static void main(String[] args)
        {        
            try
            {
                // Creation of new OutputSreamWriter
                OutputStream g = new FileOutputStream("test.txt");
                OutputStreamWriter geeks_out1 = new OutputStreamWriter(g);
      
                // Creating an Input Stream
                FileInputStream in = new FileInputStream("test.txt");
      
                // Use of write(int char) :
                // Writing character values to the "test.txt"
                geeks_out1.write(71);
                geeks_out1.write(69);
                geeks_out1.write(69);
                geeks_out1.write(75);
                geeks_out1.write(83);
      
                // flush the stream
                geeks_out1.flush();
      
                // read what we write
                for (int i = 0; i < 5; i++)
                {
                    // Reading the content of "test.txt" file
                    System.out.println("write(int char) : " + (char) in.read());
                }
                geeks_out1.close();
            }
            catch (Exception ex)
            {
                System.out.println("Error");
                ex.printStackTrace();
            }
        }
    }

    Output :

    write(int char) : G
    write(int char) : E
    write(int char) : E
    write(int char) : K
    write(int char) : S
  • write(String geek, int offset, int strlen) : java.io.OutputStreamWriter.write(String geek, int offset, int strlen) writes a portion of “geek” string starting from “offset position” upto “strlen” length.
    Syntax :
    public void write(String geek, int offset, int strlen)
    Parameters : 
    geek : string whose portion is to be written 
    offset : starting position from where to write
    strlen : length upto which we need to write
    Return : 
    void
    Exception : 
    -> IOException : if in case any I/O error occurs.
    
    // Java code explaining the working of write(String geek, int offset, int strlen))
      
    import java.io.*;
    public class NewClass
    {
        public static void main(String[] args)
        {
            String geek = "GEEKSForGeeks";
            try
            {
                // Creation of new OutputSreamWriter
                OutputStream g = new FileOutputStream("test.txt");
                OutputStreamWriter geeks_out1 = new OutputStreamWriter(g);
      
                // Creating an Input Stream
                FileInputStream in = new FileInputStream("test.txt");
      
                // Use of writewrite(String geek, int offset, int strlen)) :
                // Writing character values to the "test.txt"
                geeks_out1.write(geek, 4, 9);
      
                // flush the stream
                geeks_out1.flush();
      
                // read what we write
                for (int i = 0; i < 5; i++)
                {
                    // Reading the content of "test.txt" file
                    System.out.println("write(int char) : " + (char) in.read());
                }
                geeks_out1.close();
            }
            catch (Exception ex)
            {
                System.out.println("Error");
                ex.printStackTrace();
            }
        }
    }

    Output :

    write(int char) : S
    write(int char) : F
    write(int char) : o
    write(int char) : r
    write(int char) : G
  • write(char[] geek, int offset, int strlen) : java.io.OutputStreamWriter.write(char[] geek, int offset, int strlen) writes a portion of “geek” character array starting from “offset position” upto “strlen” length.
    Syntax :
    public void write(char[] geek, int offset, int strlen)
    Parameters : 
    geek : character array whose portion is to be written 
    offset : starting position from where to write
    strlen : length upto which we need to write
    Return : 
    void
    Exception : 
    -> IOException : if in case anu I/O error occurs.
    
  • getEncoding() : java.io.OutputStreamWriter.getEncoding() tells the name of the character encoding being used in the mentioned Stream.
    If there is predefined name exists, then it is returned otherwise canonical name of the encoding is returned.
    Returns Null, if the stream has been already closed.
    Syntax :
    public String getEncoding()
    Parameters : 
    ------
    Return : 
    Name of the charset encoding used
    Exception : 
    -> IOException : if in case anu I/O error occurs.
    
    // Java code explaining write(char[] geek, int offset, int strlen)
    // and getEncoding() method
      
    import java.io.*;
    public class NewClass
    {
        public static void main(String[] args)
        {
            char[] geek = {"G", "E", "E", "K", "S"};
            try
            {
                // Creation of new OutputSreamWriter
                OutputStream g = new FileOutputStream("test.txt");
                OutputStreamWriter geeks_out1 = new OutputStreamWriter(g);
      
                // Creating an Input Stream
                FileInputStream in = new FileInputStream("test.txt");
      
                // Use of writewrite(char[] geek, int offset, int strlen)) :
                // Writing character values to the "test.txt"
                geeks_out1.write(geek, 0, 3);
      
                // flush the stream
                geeks_out1.flush();
      
                // read what we write
                for (int i = 0; i < 3; i++)
                {
                    // Reading the content of "test.txt" file
                    System.out.println("char[] geek, int offset, int strlen) : " 
                                                                + (char) in.read());
                }
      
                // get and print the encoding for this stream
                System.out.println(" Name of the charset : "
                                            + geeks_out1.getEncoding());
                  
                // Closing the OutputStreamWriter
                geeks_out1.close();
            }
              
            catch (Exception ex)
            {
                System.out.println("Error");
                ex.printStackTrace();
            }
        }
    }

    Output :

    char[] geek, int offset, int strlen) : G
    char[] geek, int offset, int strlen) : E
    char[] geek, int offset, int strlen) : E
    
    Name of the charset : UTF8

This article is contributed by Mohit Gupta . If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

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