Classe Java StringWriter crea una cadena a partir dels caràcters del flux String Buffer. Els mètodes de la classe StringWriter a Java també es poden cridar després de tancar el flux, ja que això no generarà cap excepció d'IO. 

Declaració a la classe Java StringWriter

public class StringWriter extends Writer

Constructors a la classe StringWriter a Java

Els constructors utilitzats a la classe String Writer a Java s'esmenten a continuació:

StringWriter():Crea un StringWriter nou utilitzant la mida inicial o predeterminada de String BufferStringWriter (mida int):Crea un nou StringWriter utilitzant la mida esmentada de String Buffer

Mètodes a la classe Java StringWriter 

Tots els mètodes implicats amb la classe Java StringWriter s'esmenten a continuació:

1. escriure (int char)

java.io.StringWriter.write(int char) escriu un sol caràcter al String Buffer. 

  Syntax:   public void write(int char)   Parameters :    char : int value of the character to be written.   Return :   void

2. escriure(String str)

java.io.StringWriter.write(String str) escriu una cadena a la memòria intermèdia de cadena. 

  Syntax:   public void write(String str)   Parameters :    str : string to be written to the String Buffer.   Return :   void

3. write(String str int offset int maxlen)

java.io.StringWriter.write(String str int offset int maxlen) escriu alguna part de la cadena al String Buffer. 

  Syntax:   public void write(String str int offset int maxlen)   Parameters :    str : string to be written to the String Buffer. offset : start position of the String maxlen : maximum length upto which string has to written   Return :   void

4. write(char[] carray int offset int maxlen)

java.io.StringWriter.write(char[] carray int offset int maxlen) escriu alguna part de la matriu de caràcters al String Buffer. 

  Syntax:   public void write(char[] carray int offset int maxlen)   Parameters :    carray : character to be written to the String Buffer offset : start position of the character array maxlen : maximum no. of the character of the carray has to written   Return :   void

5. toString()

java.io.StringWriter.toString() retorna el valor de la memòria intermèdia de cadena com a cadena.

  Syntax:   public String toString()   Parameters :    -----------   Return :   string value of the String Buffer

6. tancar()

java.io.StringWriter.close() tanca String Buffer. Com que el mètode també es pot cridar després de tancar el String Buffer, no té cap paper. 

  Syntax:   public void close()   Parameters :    -----------   Return :   void

7. afegiu(car Sw)

java.io.StringWriter.append(char Sw) afegeix un sol caràcter a la memòria intermèdia de cadena. 

  Syntax:   public StringWriter append(char Sw)   Parameters :    Sw : character to be append   Return :   StringWriter

8. afegir(CharSequence char_sq)

java.io.StringWriter.append(CharSequence char_sq) afegeix la seqüència de caràcters especificada a la memòria intermèdia de cadena. 

  Syntax:   public StringWriter append(CharSequence char_sq)   Parameters :    char_sq : Character sequence to append.   Return :   StringWriter if char sequence is null then NULL appends to the StringWriter.

9. append(CharSequence char_sq int start int end)

java.io.StringWriter.append(CharSequence char_sq int start int end) afegeix una part especificada d'una seqüència de caràcters a la memòria intermèdia de cadenes. 

  Syntax:   public StringWriter append(CharSequence char_sq int start int end)   Parameters :    char_sq : Character sequence to append. start : start of character in the Char Sequence end : end of character in the Char Sequence   Return :   void

10. rentar()

java.io.StringWriter.flush() esborra el flux StringWriter.

  Syntax:   public void flush()   Parameters :    -----   Return :   void

11. getBuffer()

java.io.StringWriter.getBuffer() retorna la memòria intermèdia de StringWriter. 

  Syntax:   public StringBuffer getBuffer()   Parameters :    -----------   Return :   String Buffer with its current value.

Exemple

Programa Java que il·lustra l'ús dels mètodes de classe StringWriter: 

// Java program illustrating the working of StringWriter // class methods write(int char) write(String str) close() // write(String str int offset int maxlen) toString() // write(char[] carray int offset int maxlen) import java.io.*; public class NewClass {  public static void main(String[] args)  throws IOException  {  // Initializing String Writer  StringWriter geek_writer1 = new StringWriter();  StringWriter geek_writer2 = new StringWriter();  StringWriter geek_writer3 = new StringWriter();  StringWriter geek_writer4 = new StringWriter();  // Use of write(int char) : to write a character  geek_writer1.write(71);  geek_writer1.write(70);  geek_writer1.write(71);  // Use of toString() : Value written by write(int  // char)  System.out.println('Using write(int char) : '  + geek_writer1.toString());  String str = 'Hello Geeks';  // Use of write(String str) : to write string  geek_writer2.write(str);  // Value written by write(String str)  System.out.println('Using write(String str) : '  + geek_writer2.toString());  // Use of write(String str int offset int maxlen)  // : to write part of string  geek_writer3.write(str 2 4);  geek_writer3.write(str 5 6);  // Value written by write(String str int offset  // int maxlen)  System.out.println(  'Using write(str offset maxlen) : '  + geek_writer3.toString());  try {  // Use of Close() method : to close the  // geek_writer4 But no use as String Writer  // method is still working with it  geek_writer4.close();  }  catch (IOException except) {  System.out.println('ERROR');  except.printStackTrace();  ;  }  // Initializing character array  char[] carray = str.toCharArray();  // Use of write(char[] carray int offset int  // maxlen): to write part of char array  geek_writer4.write(carray 4 6);  // Value written by write(String str int offset  // int maxlen)  System.out.println(  'Using write(carray offset maxlen) : '  + geek_writer4.toString());  } } 

Sortida

Using write(int char) : GFG Using write(String str) : Hello Geeks Using write(str offset maxlen) : llo Geeks Using write(carray offset maxlen) : o Geek

Programa Java que il·lustra l'ús dels mètodes de classe StringWriter: append(CharSequence char_sq) append(char Sw) append(CharSequence char_sq int startint end) flush() getgetBuffer()

// Java program illustrating the working of StringWriter // class methods append(CharSequence char_sq) append(char // Sw) append(CharSequence char_sq int startint end) // flush() getgetBuffer() import java.io.*; public class NewClass {  public static void main(String[] args)  throws IOException  {  // Initializing String Writer  StringWriter geek_writer1 = new StringWriter();  StringWriter geek_writer2 = new StringWriter();  StringWriter geek_writer3 = new StringWriter();  // Use of write(int char) : to write a character  geek_writer1.write(71);  geek_writer1.write(70);  geek_writer1.write(71);  // Use of toString() : Value written by write(int  // char)  System.out.println('Using write(int char) : '  + geek_writer1.toString());  // Using flush() method  geek_writer1.flush();  System.out.println('Using flush() : '  + geek_writer1.toString());  // Use of append(char Sw)  System.out.println('append(char Sw) : '  + geek_writer1.append(' 1GFG1'));  // Use of getBuffer() :  System.out.println('Using geek_writer1 : '  + geek_writer1.getBuffer());  // Initializing Character Sequence  CharSequence char_sq1 = '1 Hello 1';  CharSequence char_sq2 = ' : 2 Geeks 2';  // Use of append(CharSequence char_sq)  geek_writer2.append(char_sq1);  geek_writer2.append(char_sq2);  System.out.println('append(char_sq) : '  + geek_writer2.toString());  // Use of append(CharSequence char_sqint startint  // end)  geek_writer3.append(char_sq1 0 3);  geek_writer3.append(char_sq2 3 6);  System.out.println('append(char_sqstartend) : '  + geek_writer3.toString());  } } 

Sortida

Using write(int char) : GFG Using flush() : GFG append(char Sw) : GFG 1GFG1 Using geek_writer1 : GFG 1GFG1 append(char_sq) : 1 Hello 1 : 2 Geeks 2 append(char_sqstartend) : 1 H2 G