java.io
public
abstract
class
java.io.Writer
Writer is an Abstract class for writing Character Streams. Subclasses of
writer must implement the methods write(char[], int, int)
,
close()
and flush()
.
Known Direct Subclasses
BufferedWriter |
BufferedWriter is for writing buffered character output. |
CharArrayWriter |
CharArrayWriter is used as a character output stream on a character array. |
FilterWriter |
FilterWriter is a class which takes a Writer and filters the
output in some way. |
OutputStreamWriter |
OutputStreamWriter is a class for turning a character output stream into a
byte output stream. |
PipedWriter |
PipedWriter is a class which places information on a communications pipe. |
PrintWriter |
PrintWriter is a class which takes either an OutputStream or Writer and
provides convenience methods for printing common data types in a human
readable format on the stream. |
StringWriter |
StringWriter is an class for writing Character Streams to a StringBuffer. |
Known Indirect Subclasses
FileWriter |
FileWriter is a class for writing characters out to a file. |
Summary
Fields
protected |
|
|
Object |
lock |
The object used to synchronize access to the writer. |
Protected Constructors
Public Methods
clone,
equals,
finalize,
getClass,
hashCode,
notify,
notifyAll,
toString,
wait,
wait,
wait
Details
Fields
protected
Object
lock
The object used to synchronize access to the writer.
Protected Constructors
protected
Writer()
Constructs a new character stream Writer using this
as the
Object to synchronize critical regions around.
protected
Writer(Object lock)
Constructs a new character stream Writer using
lock
as the
Object to synchronize critical regions around.
Parameters
lock
| the Object to synchronize critical regions around.
|
Public Methods
Append a CharSequence
csq
to the Writer. The
Writer.append(
csq
) works the same way as Writer.write(
csq
.toString()).
If
csq
is null, then "null" will be substituted for
csq
.
Parameters
csq
| The CharSequence appended to the Writer. |
Throws
IOException
| If any IOException raises during the procedure.
|
public
Writer
append(CharSequence csq, int start, int end)
Append a subsequence of a CharSequence
csq
to the Writer.
The first char and the last char of the subsequnce is specified by the
parameter
start
and
end
. The
Writer.append(
csq
) works the same way as Writer.write (
csq
csq.subSequence(
start
,
end
).toString).
If
csq
is null, then "null" will be substituted for
csq
.
Parameters
csq
| The CharSequence appended to the Writaer. |
start
| The index of the first char in the CharSequence appended to
the Writer. |
end
| The index of the char after the last one in the CharSequence
appended to the Writer. |
Throws
IndexOutOfBoundsException
| If start is less than end, end is greater than the length of
the CharSequence, or start or end is negative. |
IOException
| If any IOException raises during the procedure.
|
public
Writer
append(char c)
Append a char
c
to the Writer. The Writer.append(
c
)
works the same as Writer.write(
c
).
Parameters
c
| The character appended to the Writer. |
Throws
IOException
| If any IOException raises during the procedure.
|
public
abstract
void
close()
Close this Writer. This must be implemented by any concrete subclasses.
The implementation should free any resources associated with the Writer.
Throws
IOException
| If an error occurs attempting to close this Writer.
|
public
abstract
void
flush()
Flush this Writer. This must be implemented by any concrete subclasses.
The implementation should ensure all buffered characters are written out.
Throws
IOException
| If an error occurs attempting to flush this Writer.
|
public
abstract
void
write(char[] buf, int offset, int count)
Writes
count
characters starting at
offset in
buf
to this Writer. This abstract method must be implemented
by concrete subclasses.
Parameters
buf
| the non-null array containing characters to write. |
offset
| offset in buf to retrieve characters |
count
| maximum number of characters to write |
public
void
write(String str, int offset, int count)
Writes
count
number of characters starting at
offset
from the String
str
to this Writer.
Parameters
str
| the non-null String containing the characters to write. |
offset
| the starting point to retrieve characters. |
count
| the number of characters to retrieve and write. |
public
void
write(int oneChar)
Writes the specified character
oneChar
to this Writer.
This implementation writes the low order two bytes of
oneChar
to the Stream.
Parameters
oneChar
| The character to write |
Throws
IOException
| If this Writer has already been closed or some other
IOException occurs.
|
public
void
write(char[] buf)
Writes the entire character buffer
buf
to this Writer.
Parameters
buf
| the non-null array containing characters to write. |
Throws
IOException
| If this Writer has already been closed or some other
IOException occurs.
|
public
void
write(String str)
Writes the characters from the String
str
to this Writer.
Parameters
str
| the non-null String containing the characters to write. |
Throws
IOException
| If this Writer has already been closed or some other
IOException occurs.
|