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
importjava.io.FileNotFoundException;importjava.io.FileOutputStream;importjava.io.PrintStream;importjava.util.Locale;//Java program to demonstrate PrintStream methodsclassPrintstream{publicstaticvoidmain(Stringargs[])throwsFileNotFoundException{FileOutputStreamfout=newFileOutputStream('file.txt');//creating Printstream objPrintStreamout=newPrintStream(fout);Strings='First';//writing to file.txtcharc[]={'G''E''E''K'};//illustrating print(boolean b) methodout.print(true);//illustrating print(int i) methodout.print(1);//illustrating print(float f) methodout.print(4.533f);//illustrating print(String s) methodout.print('GeeksforGeeks');out.println();//illustrating print(Object Obj) methodout.print(fout);out.println();//illustrating append(CharSequence csq) methodout.append('Geek');out.println();//illustrating checkError() methodout.println(out.checkError());//illustrating format() methodout.format(Locale.UK'Welcome to my %s program's);//illustrating flush methodout.flush();//illustrating close methodout.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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