1. Description
2. Field Summary
3. Constructor Summary
4. Method Summary
5. Field Details
   1. lock
6. Constructor Details
   1. Writer()
   2. Writer(Object)
7. Method Details
   1. nullWriter()
   2. write(int)
   3. write(char[])
   4. write(char[], int, int)
   5. write(String)
   6. write(String, int, int)
   7. append(CharSequence)
   8. append(CharSequence, int, int)
   9. append(char)
   10. flush()
   11. close()

• Field Summary

  Fields
  Modifier and Type

  Field

  Description

  protected Object

  lock

  The object used to synchronize operations on this stream.

• Constructor Summary

  Constructors
  Modifier

  Constructor

  Description

  protected

  Writer()

  Creates a new character-stream writer whose critical sections will synchronize on the writer itself.

  protected

  Writer(Object lock)

  Creates a new character-stream writer whose critical sections will synchronize on the given object.

• Method Summary

  All MethodsStatic MethodsInstance MethodsAbstract MethodsConcrete Methods

  Modifier and Type

  Method

  Description

  Writer

  append(char c)

  Appends the specified character to this writer.

  Writer

  append(CharSequence csq)

  Appends the specified character sequence to this writer.

  Writer

  append(CharSequence csq, int start, int end)

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

  abstract void

  close()

  Closes the stream, flushing it first.

  abstract void

  flush()

  Flushes the stream.

  static Writer

  nullWriter()

  Returns a new Writer which discards all characters.

  void

  write(char[] cbuf)

  Writes an array of characters.

  abstract void

  write(char[] cbuf, int off, int len)

  Writes a portion of an array of characters.

  void

  write(int c)

  Writes a single character.

  void

  write(String str)

  Writes a string.

  void

  write(String str, int off, int len)

  Writes a portion of a string.

  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

  • lock

    protected Object lock

    The object used to synchronize operations on this stream. For efficiency, a character-stream object may use an object other than itself to protect critical sections. A subclass should therefore use the object in this field rather than this or a synchronized method.

• Constructor Details

  • Writer

    protected Writer()

    Creates a new character-stream writer whose critical sections will synchronize on the writer itself.

  • Writer

    protected Writer(Object lock)

    Creates a new character-stream writer whose critical sections will synchronize on the given object.

    Parameters: lock - Object to synchronize on

• Method Details

  • nullWriter

    public static Writer nullWriter()

    Returns a new Writer which discards all characters. The returned stream is initially open. The stream is closed by calling the close() method. Subsequent calls to close() have no effect.

    While the stream is open, the append(char), append(CharSequence), append(CharSequence, int, int), flush(), write(int), write(char[]), and write(char[], int, int) methods do nothing. After the stream has been closed, these methods all throw IOException.

    The object used to synchronize operations on the returned Writer is not specified.

    Returns: a Writer which discards all characters Since: 11

  • write

    public void write(int c) throws IOException

    Writes a single character. The character to be written is contained in the 16 low-order bits of the given integer value; the 16 high-order bits are ignored.

    Subclasses that intend to support efficient single-character output should override this method.

    Parameters: c - int specifying a character to be written Throws: IOException - If an I/O error occurs

  • write

    public void write(char[] cbuf) throws IOException

    Writes an array of characters.

    Parameters: cbuf - Array of characters to be written Throws: IOException - If an I/O error occurs

  • write

    public abstract void write(char[] cbuf, int off, int len) throws IOException

    Writes a portion of an array of characters.

    Parameters: cbuf - Array of characters off - Offset from which to start writing characters len - Number of characters to write Throws: IndexOutOfBoundsException - Implementations should throw this exception if off is negative, or len is negative, or off + len is negative or greater than the length of the given array IOException - If an I/O error occurs

  • write

    public void write(String str) throws IOException

    Writes a string.

    Parameters: str - String to be written Throws: IOException - If an I/O error occurs

  • write

    public void write(String str, int off, int len) throws IOException

    Writes a portion of a string.

    Implementation Requirements: The implementation in this class throws an IndexOutOfBoundsException for the indicated conditions; overriding methods may choose to do otherwise. Parameters: str - A String off - Offset from which to start writing characters len - Number of characters to write Throws: IndexOutOfBoundsException - Implementations should throw this exception if off is negative, or len is negative, or off + len is negative or greater than the length of the given string IOException - If an I/O error occurs

  • append

    public Writer append(CharSequence csq) throws IOException

    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 Parameters: csq - The character sequence to append. If csq is null, then the four characters "null" are appended to this writer. Returns: This writer Throws: IOException - If an I/O error occurs Since: 1.5

  • append

    public Writer append(CharSequence csq, int start, int end) throws IOException

    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 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() IOException - If an I/O error occurs Since: 1.5

  • append

    public Writer append(char c) throws IOException

    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 Parameters: c - The 16-bit character to append Returns: This writer Throws: IOException - If an I/O error occurs Since: 1.5

  • flush

    public abstract void flush() throws IOException

    Flushes the stream. If the stream has saved any characters from the various write() methods in a buffer, write them immediately to their intended destination. Then, if that destination is another character or byte stream, flush it. Thus one flush() invocation will flush all the buffers in a chain of Writers and OutputStreams.

    If the intended destination of this stream is an abstraction provided by the underlying operating system, for example a file, then flushing the stream guarantees only that bytes previously written to the stream are passed to the operating system for writing; it does not guarantee that they are actually written to a physical device such as a disk drive.

    Specified by: flush in interface Flushable Throws: IOException - If an I/O error occurs

  • close

    public abstract void close() throws IOException

    Closes the stream, flushing it first. Once the stream has been closed, further write() or flush() invocations will cause an IOException to be thrown. Closing a previously closed stream has no effect.

    Specified by: close in interface AutoCloseable Specified by: close in interface Closeable Throws: IOException - If an I/O error occurs

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