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Java.io.Printstream-klass i Java | Set 1

En PrintStream lägger till funktionalitet till en annan utdataström, nämligen möjligheten att enkelt skriva ut representationer av olika datavärden. Till skillnad från andra utströmmar kastar en PrintStream aldrig ett IOException; istället ställer exceptionella situationer bara in en intern flagga som kan testas via checkError-metoden. Alternativt kan en PrintStream skapas för att spola automatiskt. Alla tecken som skrivs ut av en PrintStream konverteras till byte med hjälp av plattformens standardteckenkodning. Klassen PrintWriter bör användas i situationer som kräver skrivning av tecken snarare än byte. Klassdeklaration
public class PrintStream extends FilterOutputStream implements Appendable Closeable
Fält
 protected OutputStream out:This is the output stream to be filtered. 
Konstruktörer och beskrivning
    PrintStream(filfil):Skapar en ny utskriftsström utan automatisk linjespolning med den angivna filen. PrintStream(File file String csn):Skapar en ny utskriftsström utan automatisk linjespolning med den angivna filen och teckenuppsättningen. PrintStream(OutputStream ut):Skapar en ny utskriftsström. PrintStream(OutputStream out boolean autoFlush) :Skapar en ny utskriftsström. PrintStream(OutputStream out boolesk autoFlush String-kodning): Skapar en ny utskriftsström. PrintStream(String fileName):Skapar en ny utskriftsström utan automatisk linjespolning med det angivna filnamnet. PrintStream(String filnamn String csn):
Metoder:
    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
    PrintStream append(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 
    boolesk 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
    protected void clearError(): Clears the internal error state of this stream.
      Syntax :  protected void clearError() 
    void close() : Closes the stream.
      Syntax :  public void close()   Overrides:   close in class FilterOutputStream
    void flush(): Flushes the stream.
      Syntax :  public void flush()   Overrides:   flush in class FilterOutputStream
    PrintStream format(Locale l String format Object... 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
    PrintStream format(String format Object... args): 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 (booleskt b): Prints a boolean value.
      Syntax :  public void print(boolean b)
    void print(char 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) 
    ogiltig utskrift (dubbel d): Prints a double-precision floating-point number.
      Syntax :  public void print(double b) 
    void print(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)
    void print (långt l): Prints a long integer.
      Syntax :  public void print(long l)
    void print(Object obj): Prints an object.
      Syntax :  public void print(Object obj)
    void print(String 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. Produktion:
true14.533GeeksforGeeks java.io.FileOutputStream@1540e19dGeek false Welcome to my First program
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