Writes text to a character-output stream, buffering characters so as to provide for the efficient writing of single characters, arrays, and strings.
The buffer size may be specified, or the default size may be accepted. The default is large enough for most purposes.
A newLine() method is provided, which uses the platform's own notion of line separator as defined by the system property line.separator. Not all platforms use the newline character ('\n') to terminate lines. Calling this method to terminate each output line is therefore preferred to writing a newline character directly.
In general, a Writer sends its output immediately to the underlying character or byte stream. Unless prompt output is required, it is advisable to wrap a BufferedWriter around any Writer whose write() operations may be costly, such as FileWriters and OutputStreamWriters. For example,
PrintWriter out = new PrintWriter(new BufferedWriter(new FileWriter("foo.out")));
Inherited Field Summary
Public Constructor Summary
BufferedWriter(Writer out)
Creates a buffered character-output stream that uses a default-sized
output buffer.
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BufferedWriter(Writer out, int sz)
Creates a new buffered character-output stream that uses an output
buffer of the given size.
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Public Method Summary
void |
close()
Closes the stream, flushing it first.
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void |
flush()
Flushes the stream.
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void |
newLine()
Writes a line separator.
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void |
write(int c)
Writes a single character.
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void | |
void |
write(char[] cbuf, int off, int len)
Writes a portion of an array of characters.
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Inherited Method Summary
Public Constructors
public BufferedWriter (Writer out)
Creates a buffered character-output stream that uses a default-sized output buffer.
Parameters
out | A Writer |
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public BufferedWriter (Writer out, int sz)
Creates a new buffered character-output stream that uses an output buffer of the given size.
Parameters
out | A Writer |
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sz | Output-buffer size, a positive integer |
Throws
IllegalArgumentException | If sz <= 0
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Public Methods
public void close ()
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.
Throws
IOException |
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public void newLine ()
Writes a line separator. The line separator string is defined by the system property line.separator, and is not necessarily a single newline ('\n') character.
Throws
IOException | If an I/O error occurs |
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public void write (int c)
Writes a single character.
Parameters
c | int specifying a character to be written |
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Throws
IOException | If an I/O error occurs |
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public void write (String s, int off, int len)
Writes a portion of a String.
If the value of the len parameter is negative then no
characters are written. This is contrary to the specification of this
method in the {@linkplain java.io.Writer#write(java.lang.String,int,int)
superclass}, which requires that an IndexOutOfBoundsException
be
thrown.
Parameters
s | String to be written |
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off | Offset from which to start reading characters |
len | Number of characters to be written |
Throws
IOException | If an I/O error occurs |
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public void write (char[] cbuf, int off, int len)
Writes a portion of an array of characters.
Ordinarily this method stores characters from the given array into
this stream's buffer, flushing the buffer to the underlying stream as
needed. If the requested length is at least as large as the buffer,
however, then this method will flush the buffer and write the characters
directly to the underlying stream. Thus redundant
BufferedWriter
s will not copy data unnecessarily.
Parameters
cbuf | A character array |
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off | Offset from which to start reading characters |
len | Number of characters to write |
Throws
IOException | If an I/O error occurs |
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