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Classe Java.io.Printstream in Java | Insieme 1

Un PrintStream aggiunge funzionalità a un altro flusso di output, ovvero la capacità di stampare comodamente rappresentazioni di vari valori di dati. A differenza di altri flussi di output, PrintStream non genera mai una IOException; situazioni eccezionali invece impostano semplicemente un flag interno che può essere testato tramite il metodo checkError. Facoltativamente è possibile creare un PrintStream in modo da eseguire lo svuotamento automatico. Tutti i caratteri stampati da PrintStream vengono convertiti in byte utilizzando la codifica dei caratteri predefinita della piattaforma. La classe PrintWriter deve essere utilizzata in situazioni che richiedono la scrittura di caratteri anziché di byte. Dichiarazione di classe
public class PrintStream extends FilterOutputStream implements Appendable Closeable
Campo
 protected OutputStream out:This is the output stream to be filtered. 
Costruttori e descrizione
    PrintStream(File):Crea un nuovo flusso di stampa senza svuotamento automatico della riga con il file specificato. PrintStream(File file String csn):Crea un nuovo flusso di stampa senza svuotamento automatico della riga con il file e il set di caratteri specificati. PrintStream(OutputStream in uscita):Crea un nuovo flusso di stampa. PrintStream(OutputStream out booleano autoFlush) :Crea un nuovo flusso di stampa. PrintStream (OutputStream out codifica booleana autoFlush String): crea un nuovo flusso di stampa. PrintStream(String nomefile):Crea un nuovo flusso di stampa senza svuotamento automatico della riga con il nome file specificato. PrintStream(String fileName String csn):Crea un nuovo flusso di stampa senza svuotamento automatico della riga con il nome file e il set di caratteri specificati.
Metodi:
    PrintStream append(char c): Appends the specified character to this output stream.
      Syntax :  public PrintStream append(char c)   Parameters:   c - The 16-bit character to append   Returns:   This output stream
    PrintStream append(CharSequence csq int start int end): Appends the specified character sequence to this output stream.
      Syntax :  public PrintStream append(CharSequence csq int start int end)   Parameters:   csq - The character sequence from which a subsequence will be appended. start - The index of the first character in the subsequence end - The index of the character following the last character in the subsequence   Returns:   This output stream   Throws:   IndexOutOfBoundsException
    Aggiungi PrintStream (CharSequence csq): Appends a subsequence of the specified character sequence to this output stream.
      Syntax :  public PrintStream append(CharSequence csq)   Parameters:   csq - The character sequence to append.   Returns:   This output stream 
    booleano checkError(): Flushes the stream and checks its error state.
      Syntax :  public boolean checkError()   Returns:   true if and only if this stream has encountered an IOException other than InterruptedIOException or the setError method has been invoked
    protetto void clearError() : Clears the internal error state of this stream.
      Syntax :  protected void clearError() 
    vuoto vicino() : Closes the stream.
      Syntax :  public void close()   Overrides:   close in class FilterOutputStream
    svuotamento(): Flushes the stream.
      Syntax :  public void flush()   Overrides:   flush in class FilterOutputStream
    Formato PrintStream (oggetto formato stringa locale l... args): Writes a formatted string to this output stream using the specified format string and arguments.
      Syntax :  public PrintStream format(Locale l String format Object... args)   Parameters:   l - The locale to apply during formatting. If l is null then no localization is applied. format - A format string as described in Format string syntax args - Arguments referenced by the format specifiers in the format string. The number of arguments is variable and may be zero.   Returns:   This output stream   Throws:   IllegalFormatException NullPointerException
    Formato PrintStream (oggetto formato stringa... argomenti): Writes a formatted string to this output stream using the specified format string and arguments.
      Syntax :  public PrintStream format(String format Object... args)   Parameters  : format - A format string as described in Format string syntax args - Arguments referenced by the format specifiers in the format string. The number of arguments is variable and may be zero.   Returns:   This output stream   Throws:   IllegalFormatException NullPointerException 
    void print(booleano b): Prints a boolean value.
      Syntax :  public void print(boolean b)
    stampa vuota(carattere c): Prints a character.
      Syntax :  public void print(char c)
    void print(char[] s): Prints an array of characters.
      Syntax :  public void print(char[] s) 
    stampa vuota(doppia d): Prints a double-precision floating-point number.
      Syntax :  public void print(double b) 
    stampa vuota(float f): Prints a floating-point number.
      Syntax :  public void print(float f)
    void print(int i): Prints an integer.
      Syntax :  public void print(int i)
    stampa vuota(lunga l): Prints a long integer.
      Syntax :  public void print(long l)
    void print(Oggetto oggetto): Prints an object.
      Syntax :  public void print(Object obj)
    stampa nulla(Stringa s): Prints a string.
      Syntax :  public void print(String s)
Java
import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.PrintStream; import java.util.Locale; //Java program to demonstrate PrintStream methods class Printstream {  public static void main(String args[]) throws FileNotFoundException  {  FileOutputStream fout=new FileOutputStream('file.txt');    //creating Printstream obj  PrintStream out=new PrintStream(fout);  String s='First';  //writing to file.txt  char c[]={'G''E''E''K'};    //illustrating print(boolean b) method  out.print(true);    //illustrating print(int i) method  out.print(1);    //illustrating print(float f) method  out.print(4.533f);    //illustrating print(String s) method  out.print('GeeksforGeeks');  out.println();    //illustrating print(Object Obj) method  out.print(fout);  out.println();    //illustrating append(CharSequence csq) method  out.append('Geek');  out.println();    //illustrating checkError() method  out.println(out.checkError());    //illustrating format() method  out.format(Locale.UK 'Welcome to my %s program' s);    //illustrating flush method  out.flush();    //illustrating close method  out.close();  } } 
Note: The output might not be visible on online IDE as it is not able to read the file. Produzione:
true14.533GeeksforGeeks java.io.FileOutputStream@1540e19dGeek false Welcome to my First program
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