java.io
Class Writer

java.lang.Object
 |
 +--java.io.Writer

Direct Known Subclasses:

BufferedWriter, CharArrayWriter, FilterWriter, OutputStreamWriter, PipedWriter, PrintStreamWriter, PrintWriter, StringWriter

public abstract class Writer

extends Object

Untamed: Abstract class for writing to character streams. The only methods that a subclass must implement are write(char[], int, int), flush(), and close(). Most subclasses, however, will override some of the methods defined here in order to provide higher efficiency, additional functionality, or both.

Since:

JDK1.1

Version:

1.20, 01/12/03

Author:

Mark Reinhold

See Also:

Writer, BufferedWriter, CharArrayWriter, FilterWriter, OutputStreamWriter, FileWriter, PipedWriter, PrintWriter, StringWriter, Reader

writeBuffer

private char[] writeBuffer

Temporary buffer used to hold writes of strings and single characters

writeBufferSize

private final int writeBufferSize

Size of writeBuffer, must be>= 1

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.

Writer

protected Writer()

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

Writer

protected Writer(Object lock)

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

Parameters:

lock - Object to synchronize on.

write

public void write(int c)
 throws IOException

Enabled: Write 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.

IOException

write

public void write(char[] cbuf)
 throws IOException

Enabled: Write an array of characters.

Parameters:

cbuf - Array of characters to be written

IOException

write

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

Enabled: Write 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

IOException

write

public void write(String str)
 throws IOException

Enabled: Write a string.

Parameters:

str - String to be written

IOException

write

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

Enabled: Write a portion of a string.

Parameters:

str - A String

off - Offset from which to start writing characters

len - Number of characters to write

IOException

flush

public abstract void flush()
 throws IOException

Enabled: Flush 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.

IOException

close

public abstract void close()
 throws IOException

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

IOException