1. Description
2. Field Summary
3. Constructor Summary
4. Method Summary
   1. Methods declared in class Writer
   2. Methods declared in class Object
5. Field Details
   1. out
6. Constructor Details
   1. PrintWriter(Writer)
   2. PrintWriter(Writer, boolean)
   3. PrintWriter(OutputStream)
   4. PrintWriter(OutputStream, boolean)
   5. PrintWriter(OutputStream, boolean, Charset)
   6. PrintWriter(String)
   7. PrintWriter(String, String)
   8. PrintWriter(String, Charset)
   9. PrintWriter(File)
   10. PrintWriter(File, String)
   11. PrintWriter(File, Charset)
7. Method Details
   1. flush()
   2. close()
   3. checkError()
   4. setError()
   5. clearError()
   6. write(int)
   7. write(char[], int, int)
   8. write(char[])
   9. write(String, int, int)
   10. write(String)
   11. print(boolean)
   12. print(char)
   13. print(int)
   14. print(long)
   15. print(float)
   16. print(double)
   17. print(char[])
   18. print(String)
   19. print(Object)
   20. println()
   21. println(boolean)
   22. println(char)
   23. println(int)
   24. println(long)
   25. println(float)
   26. println(double)
   27. println(char[])
   28. println(String)
   29. println(Object)
   30. printf(String, Object...)
   31. printf(Locale, String, Object...)
   32. format(String, Object...)
   33. format(Locale, String, Object...)
   34. append(CharSequence)
   35. append(CharSequence, int, int)
   36. append(char)

• Field Summary

  Fields
  Modifier and Type

  Field

  Description

  protected Writer

  out

  The underlying character-output stream of this PrintWriter.

  Fields declared in class Writer

  lock

  Modifier and Type

  Field

  Description

  protected Object

  lock

  The object used to synchronize operations on this stream.

• Constructor Summary

  Constructors
  Constructor

  Description

  PrintWriter(File file)

  Creates a new PrintWriter, without automatic line flushing, with the specified file.

  PrintWriter(File file, String csn)

  Creates a new PrintWriter, without automatic line flushing, with the specified file and charset.

  PrintWriter(File file, Charset charset)

  Creates a new PrintWriter, without automatic line flushing, with the specified file and charset.

  PrintWriter(OutputStream out)

  Creates a new PrintWriter, without automatic line flushing, from an existing OutputStream.

  PrintWriter(OutputStream out, boolean autoFlush)

  Creates a new PrintWriter from an existing OutputStream.

  PrintWriter(OutputStream out, boolean autoFlush, Charset charset)

  Creates a new PrintWriter from an existing OutputStream.

  PrintWriter(Writer out)

  Creates a new PrintWriter, without automatic line flushing.

  PrintWriter(Writer out, boolean autoFlush)

  Creates a new PrintWriter.

  PrintWriter(String fileName)

  Creates a new PrintWriter, without automatic line flushing, with the specified file name.

  PrintWriter(String fileName, String csn)

  Creates a new PrintWriter, without automatic line flushing, with the specified file name and charset.

  PrintWriter(String fileName, Charset charset)

  Creates a new PrintWriter, without automatic line flushing, with the specified file name and charset.

• Method Summary

  All MethodsInstance MethodsConcrete Methods

  Modifier and Type

  Method

  Description

  PrintWriter

  append(char c)

  Appends the specified character to this writer.

  PrintWriter

  append(CharSequence csq)

  Appends the specified character sequence to this writer.

  PrintWriter

  append(CharSequence csq, int start, int end)

  Appends a subsequence of the specified character sequence to this writer.

  boolean

  checkError()

  Flushes the stream if it's not closed and checks its error state.

  protected void

  clearError()

  Clears the error state of this stream.

  void

  close()

  Closes the stream and releases any system resources associated with it.

  void

  flush()

  Flushes the stream.

  PrintWriter

  format(String format, Object... args)

  Writes a formatted string to this writer using the specified format string and arguments.

  PrintWriter

  format(Locale l, String format, Object... args)

  Writes a formatted string to this writer using the specified format string and arguments.

  void

  print(boolean b)

  Prints a boolean value.

  void

  print(char c)

  Prints a character.

  void

  print(char[] s)

  Prints an array of characters.

  void

  print(double d)

  Prints a double-precision floating-point number.

  void

  print(float f)

  Prints a floating-point number.

  void

  print(int i)

  Prints an integer.

  void

  print(long l)

  Prints a long integer.

  void

  print(Object obj)

  Prints an object.

  void

  print(String s)

  Prints a string.

  PrintWriter

  printf(String format, Object... args)

  A convenience method to write a formatted string to this writer using the specified format string and arguments.

  PrintWriter

  printf(Locale l, String format, Object... args)

  A convenience method to write a formatted string to this writer using the specified format string and arguments.

  void

  println()

  Terminates the current line by writing the line separator string.

  void

  println(boolean x)

  Prints a boolean value and then terminates the line.

  void

  println(char x)

  Prints a character and then terminates the line.

  void

  println(char[] x)

  Prints an array of characters and then terminates the line.

  void

  println(double x)

  Prints a double-precision floating-point number and then terminates the line.

  void

  println(float x)

  Prints a floating-point number and then terminates the line.

  void

  println(int x)

  Prints an integer and then terminates the line.

  void

  println(long x)

  Prints a long integer and then terminates the line.

  void

  println(Object x)

  Prints an Object and then terminates the line.

  void

  println(String x)

  Prints a String and then terminates the line.

  protected void

  setError()

  Sets the error state of the stream to true.

  void

  write(char[] buf)

  Writes an array of characters.

  void

  write(char[] buf, int off, int len)

  Writes A Portion of an array of characters.

  void

  write(int c)

  Writes a single character.

  void

  write(String s)

  Writes a string.

  void

  write(String s, int off, int len)

  Writes a portion of a string.

  Methods declared in class Writer

  nullWriter

  Modifier and Type

  Method

  Description

  static Writer

  nullWriter()

  Returns a new Writer which discards all characters.

  Methods declared in class Object

  clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  Modifier and Type

  Method

  Description

  protected Object

  clone()

  Creates and returns a copy of this object.

  boolean

  equals(Object obj)

  Indicates whether some other object is "equal to" this one.

  protected void

  finalize()

  Deprecated, for removal: This API element is subject to removal in a future version.

  Finalization is deprecated and subject to removal in a future release.

  final Class<?>

  getClass()

  Returns the runtime class of this Object.

  int

  hashCode()

  Returns a hash code value for this object.

  final void

  notify()

  Wakes up a single thread that is waiting on this object's monitor.

  final void

  notifyAll()

  Wakes up all threads that are waiting on this object's monitor.

  String

  toString()

  Returns a string representation of the object.

  final void

  wait()

  Causes the current thread to wait until it is awakened, typically by being notified or interrupted.

  final void

  wait(long timeoutMillis)

  Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

  final void

  wait(long timeoutMillis, int nanos)

  Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

• Field Details

  • out

    protected Writer out

    The underlying character-output stream of this PrintWriter.

    Since: 1.2

• Constructor Details

  • PrintWriter

    public PrintWriter(Writer out)

    Creates a new PrintWriter, without automatic line flushing.

    Parameters: out - A character-output stream

  • PrintWriter

    public PrintWriter(Writer out, boolean autoFlush)

    Creates a new PrintWriter.

    Parameters: out - A character-output stream autoFlush - A boolean; if true, the println, printf, or format methods will flush the output buffer

  • PrintWriter

    public PrintWriter(OutputStream out)

    Creates a new PrintWriter, without automatic line flushing, from an existing OutputStream. This convenience constructor creates the necessary intermediate OutputStreamWriter, which will convert characters into bytes using the default charset, or where out is a PrintStream, the charset used by the print stream.

    Parameters: out - An output stream See Also:

    • OutputStreamWriter(OutputStream)
    • Charset.defaultCharset()

  • PrintWriter

    public PrintWriter(OutputStream out, boolean autoFlush)

    Creates a new PrintWriter from an existing OutputStream. This convenience constructor creates the necessary intermediate OutputStreamWriter, which will convert characters into bytes using the default charset, or where out is a PrintStream, the charset used by the print stream.

    Parameters: out - An output stream autoFlush - A boolean; if true, the println, printf, or format methods will flush the output buffer See Also:

    • OutputStreamWriter(OutputStream)
    • Charset.defaultCharset()

  • PrintWriter

    public PrintWriter(OutputStream out, boolean autoFlush, Charset charset)

    Creates a new PrintWriter from an existing OutputStream. This convenience constructor creates the necessary intermediate OutputStreamWriter, which will convert characters into bytes using the specified charset.

    Parameters: out - An output stream autoFlush - A boolean; if true, the println, printf, or format methods will flush the output buffer charset - A charset Since: 10

  • PrintWriter

    public PrintWriter(String fileName) throws FileNotFoundException

    Creates a new PrintWriter, without automatic line flushing, with the specified file name. This convenience constructor creates the necessary intermediate OutputStreamWriter, which will encode characters using the default charset for this instance of the Java virtual machine.

    Parameters: fileName - The name of the file to use as the destination of this writer. If the file exists then it will be truncated to zero size; otherwise, a new file will be created. The output will be written to the file and is buffered. Throws: FileNotFoundException - If the given string does not denote an existing, writable regular file and a new regular file of that name cannot be created, or if some other error occurs while opening or creating the file Since: 1.5 See Also:

    • Charset.defaultCharset()

  • PrintWriter

    public PrintWriter(String fileName, String csn) throws FileNotFoundException, UnsupportedEncodingException

    Creates a new PrintWriter, without automatic line flushing, with the specified file name and charset. This convenience constructor creates the necessary intermediate OutputStreamWriter, which will encode characters using the provided charset.

    Parameters: fileName - The name of the file to use as the destination of this writer. If the file exists then it will be truncated to zero size; otherwise, a new file will be created. The output will be written to the file and is buffered. csn - The name of a supported charset Throws: FileNotFoundException - If the given string does not denote an existing, writable regular file and a new regular file of that name cannot be created, or if some other error occurs while opening or creating the file UnsupportedEncodingException - If the named charset is not supported Since: 1.5

  • PrintWriter

    public PrintWriter(String fileName, Charset charset) throws IOException

    Creates a new PrintWriter, without automatic line flushing, with the specified file name and charset. This convenience constructor creates the necessary intermediate OutputStreamWriter, which will encode characters using the provided charset.

    Parameters: fileName - The name of the file to use as the destination of this writer. If the file exists then it will be truncated to zero size; otherwise, a new file will be created. The output will be written to the file and is buffered. charset - A charset Throws: IOException - if an I/O error occurs while opening or creating the file Since: 10

  • PrintWriter

    public PrintWriter(File file) throws FileNotFoundException

    Creates a new PrintWriter, without automatic line flushing, with the specified file. This convenience constructor creates the necessary intermediate OutputStreamWriter, which will encode characters using the default charset for this instance of the Java virtual machine.

    Parameters: file - The file to use as the destination of this writer. If the file exists then it will be truncated to zero size; otherwise, a new file will be created. The output will be written to the file and is buffered. Throws: FileNotFoundException - If the given file object does not denote an existing, writable regular file and a new regular file of that name cannot be created, or if some other error occurs while opening or creating the file Since: 1.5 See Also:

    • Charset.defaultCharset()

  • PrintWriter

    public PrintWriter(File file, String csn) throws FileNotFoundException, UnsupportedEncodingException

    Creates a new PrintWriter, without automatic line flushing, with the specified file and charset. This convenience constructor creates the necessary intermediate OutputStreamWriter, which will encode characters using the provided charset.

    Parameters: file - The file to use as the destination of this writer. If the file exists then it will be truncated to zero size; otherwise, a new file will be created. The output will be written to the file and is buffered. csn - The name of a supported charset Throws: FileNotFoundException - If the given file object does not denote an existing, writable regular file and a new regular file of that name cannot be created, or if some other error occurs while opening or creating the file UnsupportedEncodingException - If the named charset is not supported Since: 1.5

  • PrintWriter

    public PrintWriter(File file, Charset charset) throws IOException

    Creates a new PrintWriter, without automatic line flushing, with the specified file and charset. This convenience constructor creates the necessary intermediate OutputStreamWriter, which will encode characters using the provided charset.

    Parameters: file - The file to use as the destination of this writer. If the file exists then it will be truncated to zero size; otherwise, a new file will be created. The output will be written to the file and is buffered. charset - A charset Throws: IOException - if an I/O error occurs while opening or creating the file Since: 10

• Method Details

  • flush

    public void flush()

    Flushes the stream.

    Specified by: flush in interface Flushable Specified by: flush in class Writer See Also:

    • checkError()

  • close

    public void close()

    Closes the stream and releases any system resources associated with it. Closing a previously closed stream has no effect.

    Specified by: close in interface AutoCloseable Specified by: close in interface Closeable Specified by: close in class Writer See Also:

    • checkError()

  • checkError

    public boolean checkError()

    Flushes the stream if it's not closed and checks its error state.

    Returns: true if and only if this stream has encountered an IOException, or the setError method has been invoked

  • setError

    protected void setError()

    Sets the error state of the stream to true.

    This method will cause subsequent invocations of checkError() to return true until clearError() is invoked.

  • clearError

    protected void clearError()

    Clears the error state of this stream.

    This method will cause subsequent invocations of checkError() to return false until another write operation fails and invokes setError().

    Since: 1.6

  • write

    public void write(int c)

    Writes a single character.

    Overrides: write in class Writer Parameters: c - int specifying a character to be written.

  • write

    public void write(char[] buf, int off, int len)

    Writes A Portion of an array of characters.

    Specified by: write in class Writer Parameters: buf - Array of characters off - Offset from which to start writing characters len - Number of characters to write Throws: IndexOutOfBoundsException - If the values of the off and len parameters cause the corresponding method of the underlying Writer to throw an IndexOutOfBoundsException

  • write

    public void write(char[] buf)

    Writes an array of characters. This method cannot be inherited from the Writer class because it must suppress I/O exceptions.

    Overrides: write in class Writer Parameters: buf - Array of characters to be written

  • write

    public void write(String s, int off, int len)

    Writes a portion of a string.

    Overrides: write in class Writer Parameters: s - A String off - Offset from which to start writing characters len - Number of characters to write Throws: IndexOutOfBoundsException - If the values of the off and len parameters cause the corresponding method of the underlying Writer to throw an IndexOutOfBoundsException

  • write

    public void write(String s)

    Writes a string. This method cannot be inherited from the Writer class because it must suppress I/O exceptions.

    Overrides: write in class Writer Parameters: s - String to be written

  • print

    public void print(boolean b)

    Prints a boolean value. The string produced by String.valueOf(boolean) is translated into bytes according to the default charset, and these bytes are written in exactly the manner of the write(int) method.

    Parameters: b - The boolean to be printed See Also:

    • Charset.defaultCharset()

  • print

    public void print(char c)

    Prints a character. The character is translated into one or more bytes according to the default charset, and these bytes are written in exactly the manner of the write(int) method.

    Parameters: c - The char to be printed See Also:

    • Charset.defaultCharset()

  • print

    public void print(int i)

    Prints an integer. The string produced by String.valueOf(int) is translated into bytes according to the default charset, and these bytes are written in exactly the manner of the write(int) method.

    Parameters: i - The int to be printed See Also:

    • Integer.toString(int)
    • Charset.defaultCharset()

  • print

    public void print(long l)

    Prints a long integer. The string produced by String.valueOf(long) is translated into bytes according to the default charset, and these bytes are written in exactly the manner of the write(int) method.

    Parameters: l - The long to be printed See Also:

    • Long.toString(long)
    • Charset.defaultCharset()

  • print

    public void print(float f)

    Prints a floating-point number. The string produced by String.valueOf(float) is translated into bytes according to the default charset, and these bytes are written in exactly the manner of the write(int) method.

    Parameters: f - The float to be printed See Also:

    • Float.toString(float)
    • Charset.defaultCharset()

  • print

    public void print(double d)

    Prints a double-precision floating-point number. The string produced by String.valueOf(double) is translated into bytes according to the default charset, and these bytes are written in exactly the manner of the write(int) method.

    Parameters: d - The double to be printed See Also:

    • Double.toString(double)
    • Charset.defaultCharset()

  • print

    public void print(char[] s)

    Prints an array of characters. The characters are converted into bytes according to the default charset, and these bytes are written in exactly the manner of the write(int) method.

    Parameters: s - The array of chars to be printed Throws: NullPointerException - If s is null See Also:

    • Charset.defaultCharset()

  • print

    public void print(String s)

    Prints a string. If the argument is null then the string "null" is printed. Otherwise, the string's characters are converted into bytes according to the default charset, and these bytes are written in exactly the manner of the write(int) method.

    Parameters: s - The String to be printed See Also:

    • Charset.defaultCharset()

  • print

    public void print(Object obj)

    Prints an object. The string produced by the String.valueOf(Object) method is translated into bytes according to the default charset, and these bytes are written in exactly the manner of the write(int) method.

    Parameters: obj - The Object to be printed See Also:

    • Object.toString()
    • Charset.defaultCharset()

  • println

    public void println()

    Terminates the current line by writing the line separator string. The line separator is System.lineSeparator() and is not necessarily a single newline character ('\n').

  • println

    public void println(boolean x)

    Prints a boolean value and then terminates the line. This method behaves as though it invokes print(boolean) and then println().

    Parameters: x - the boolean value to be printed

  • println

    public void println(char x)

    Prints a character and then terminates the line. This method behaves as though it invokes print(char) and then println().

    Parameters: x - the char value to be printed

  • println

    public void println(int x)

    Prints an integer and then terminates the line. This method behaves as though it invokes print(int) and then println().

    Parameters: x - the int value to be printed

  • println

    public void println(long x)

    Prints a long integer and then terminates the line. This method behaves as though it invokes print(long) and then println().

    Parameters: x - the long value to be printed

  • println

    public void println(float x)

    Prints a floating-point number and then terminates the line. This method behaves as though it invokes print(float) and then println().

    Parameters: x - the float value to be printed

  • println

    public void println(double x)

    Prints a double-precision floating-point number and then terminates the line. This method behaves as though it invokes print(double) and then println().

    Parameters: x - the double value to be printed

  • println

    public void println(char[] x)

    Prints an array of characters and then terminates the line. This method behaves as though it invokes print(char[]) and then println().

    Parameters: x - the array of char values to be printed

  • println

    public void println(String x)

    Prints a String and then terminates the line. This method behaves as though it invokes print(String) and then println().

    Parameters: x - the String value to be printed

  • println

    public void println(Object x)

    Prints an Object and then terminates the line. This method calls at first String.valueOf(x) to get the printed object's string value, then behaves as though it invokes print(String) and then println().

    Parameters: x - The Object to be printed.

  • printf

    public PrintWriter printf(String format, Object... args)

    A convenience method to write a formatted string to this writer using the specified format string and arguments. If automatic flushing is enabled, calls to this method will flush the output buffer.

    An invocation of this method of the form out.printf(format, args) behaves in exactly the same way as the invocation

    Copy out.format(format, args)

    Parameters: format - A format string as described in Format string syntax. args - Arguments referenced by the format specifiers in the format string. If there are more arguments than format specifiers, the extra arguments are ignored. The number of arguments is variable and may be zero. The maximum number of arguments is limited by the maximum dimension of a Java array as defined by The Java Virtual Machine Specification. The behaviour on a null argument depends on the conversion. Returns: This writer Throws: IllegalFormatException - If a format string contains an illegal syntax, a format specifier that is incompatible with the given arguments, insufficient arguments given the format string, or other illegal conditions. For specification of all possible formatting errors, see the Details section of the formatter class specification. NullPointerException - If the format is null Since: 1.5

  • printf

    public PrintWriter printf(Locale l, String format, Object... args)

    A convenience method to write a formatted string to this writer using the specified format string and arguments. If automatic flushing is enabled, calls to this method will flush the output buffer.

    An invocation of this method of the form out.printf(l, format, args) behaves in exactly the same way as the invocation

    Copy out.format(l, format, 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. If there are more arguments than format specifiers, the extra arguments are ignored. The number of arguments is variable and may be zero. The maximum number of arguments is limited by the maximum dimension of a Java array as defined by The Java Virtual Machine Specification. The behaviour on a null argument depends on the conversion. Returns: This writer Throws: IllegalFormatException - If a format string contains an illegal syntax, a format specifier that is incompatible with the given arguments, insufficient arguments given the format string, or other illegal conditions. For specification of all possible formatting errors, see the Details section of the formatter class specification. NullPointerException - If the format is null Since: 1.5

  • format

    public PrintWriter format(String format, Object... args)

    Writes a formatted string to this writer using the specified format string and arguments. If automatic flushing is enabled, calls to this method will flush the output buffer.

    The locale always used is the one returned by Locale.getDefault(), regardless of any previous invocations of other formatting methods on this object.

    Parameters: format - A format string as described in Format string syntax. args - Arguments referenced by the format specifiers in the format string. If there are more arguments than format specifiers, the extra arguments are ignored. The number of arguments is variable and may be zero. The maximum number of arguments is limited by the maximum dimension of a Java array as defined by The Java Virtual Machine Specification. The behaviour on a null argument depends on the conversion. Returns: This writer Throws: IllegalFormatException - If a format string contains an illegal syntax, a format specifier that is incompatible with the given arguments, insufficient arguments given the format string, or other illegal conditions. For specification of all possible formatting errors, see the Details section of the Formatter class specification. NullPointerException - If the format is null Since: 1.5

  • format

    public PrintWriter format(Locale l, String format, Object... args)

    Writes a formatted string to this writer using the specified format string and arguments. If automatic flushing is enabled, calls to this method will flush the output buffer.

    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. If there are more arguments than format specifiers, the extra arguments are ignored. The number of arguments is variable and may be zero. The maximum number of arguments is limited by the maximum dimension of a Java array as defined by The Java Virtual Machine Specification. The behaviour on a null argument depends on the conversion. Returns: This writer Throws: IllegalFormatException - If a format string contains an illegal syntax, a format specifier that is incompatible with the given arguments, insufficient arguments given the format string, or other illegal conditions. For specification of all possible formatting errors, see the Details section of the formatter class specification. NullPointerException - If the format is null Since: 1.5

  • append

    public PrintWriter append(CharSequence csq)

    Appends the specified character sequence to this writer.

    An invocation of this method of the form out.append(csq) when csq is not null, behaves in exactly the same way as the invocation

    Copy out.write(csq.toString())

    Depending on the specification of toString for the character sequence csq, the entire sequence may not be appended. For instance, invoking the toString method of a character buffer will return a subsequence whose content depends upon the buffer's position and limit.

    Specified by: append in interface Appendable Overrides: append in class Writer Parameters: csq - The character sequence to append. If csq is null, then the four characters "null" are appended to this writer. Returns: This writer Since: 1.5

  • append

    public PrintWriter append(CharSequence csq, int start, int end)

    Appends a subsequence of the specified character sequence to this writer.

    An invocation of this method of the form out.append(csq, start, end) when csq is not null, behaves in exactly the same way as the invocation

    Copy out.write(csq.subSequence(start, end).toString())

    Specified by: append in interface Appendable Overrides: append in class Writer Parameters: csq - The character sequence from which a subsequence will be appended. If csq is null, then characters will be appended as if csq contained the four characters "null". 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 writer Throws: IndexOutOfBoundsException - If start or end are negative, start is greater than end, or end is greater than csq.length() Since: 1.5

  • append

    public PrintWriter append(char c)

    Appends the specified character to this writer.

    An invocation of this method of the form out.append(c) behaves in exactly the same way as the invocation

    Copy out.write(c)

    Specified by: append in interface Appendable Overrides: append in class Writer Parameters: c - The 16-bit character to append Returns: This writer Since: 1.5

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