Closeable
, AutoCloseable
, Readable
public class LongLineBufferedReader extends Reader
BufferedReader
with improved performance reading files with long lines.
This class is almost identical to BufferedReader, but it retains a single line buffer for accumulating characters in a line, and allows
its size to grow. Conversely, BufferedReader
assumes each new line will be approximately 80 characters and its
performance suffers when that is not the case.
Unlike BufferedReader
, this class is not thread safe.Constructor | Description |
---|---|
LongLineBufferedReader(Reader in) |
Creates a buffering character-input stream that uses a default-sized
input buffer.
|
LongLineBufferedReader(Reader in,
int sz) |
Creates a buffering character-input stream that uses an input buffer of
the specified size.
|
Modifier and Type | Method | Description |
---|---|---|
void |
close() |
|
void |
mark(int readAheadLimit) |
Marks the present position in the stream.
|
boolean |
markSupported() |
Tells whether this stream supports the mark() operation, which it does.
|
int |
read() |
Reads a single character.
|
int |
read(char[] cbuf,
int off,
int len) |
Reads characters into a portion of an array.
|
String |
readLine() |
Reads a line of text.
|
boolean |
ready() |
Tells whether this stream is ready to be read.
|
void |
reset() |
Resets the stream to the most recent mark.
|
long |
skip(long n) |
Skips characters.
|
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
read, read, transferTo
public LongLineBufferedReader(Reader in, int sz)
in
- A Readersz
- Input-buffer sizeIllegalArgumentException
- If sz is <= 0public LongLineBufferedReader(Reader in)
in
- A Readerpublic int read() throws IOException
read
in class Reader
IOException
- If an I/O error occurspublic int read(char[] cbuf, int off, int len) throws IOException
This method implements the general contract of the corresponding
method of the
read
class. As an additional convenience, it
attempts to read as many characters as possible by repeatedly invoking
the Reader
read
method of the underlying stream. This iterated
read
continues until one of the following conditions becomes
true:
read
method of the underlying stream returns
-1
, indicating end-of-file, or
ready
method of the underlying stream
returns false
, indicating that further input requests
would block.
read
on the underlying stream returns
-1
to indicate end-of-file then this method returns
-1
. Otherwise this method returns the number of characters
actually read.
Subclasses of this class are encouraged, but not required, to attempt to read as many characters as possible in the same fashion.
Ordinarily this method takes characters from this stream's character
buffer, filling it from the underlying stream as necessary. If,
however, the buffer is empty, the mark is not valid, and the requested
length is at least as large as the buffer, then this method will read
characters directly from the underlying stream into the given array.
Thus redundant BufferedReaderTwo
s will not copy data
unnecessarily.
read
in class Reader
cbuf
- Destination bufferoff
- Offset at which to start storing characterslen
- Maximum number of characters to readIOException
- If an I/O error occurspublic String readLine() throws IOException
IOException
- If an I/O error occurspublic long skip(long n) throws IOException
skip
in class Reader
n
- The number of characters to skipIllegalArgumentException
- If n
is negative.IOException
- If an I/O error occurspublic boolean ready() throws IOException
ready
in class Reader
IOException
- If an I/O error occurspublic boolean markSupported()
markSupported
in class Reader
public void mark(int readAheadLimit) throws IOException
mark
in class Reader
readAheadLimit
- Limit on the number of characters that may be
read while still preserving the mark. An attempt
to reset the stream after reading characters
up to this limit or beyond may fail.
A limit value larger than the size of the input
buffer will cause a new buffer to be allocated
whose size is no smaller than limit.
Therefore large values should be used with care.IllegalArgumentException
- If readAheadLimit is < 0IOException
- If an I/O error occurspublic void reset() throws IOException
reset
in class Reader
IOException
- If the stream has never been marked,
or if the mark has been invalidatedpublic void close() throws IOException
close
in interface AutoCloseable
close
in interface Closeable
close
in class Reader
IOException