java.lang.Object java.io.Reader java.io.BufferedReader
Read text from a character-input stream, buffering characters so as to provide for the efficient reading of characters, arrays, and lines.
The buffer size may be specified, or the default size may be used. The default is large enough for most purposes.
In general, each read request made of a Reader causes a corresponding read request to be made of the underlying character or byte stream. It is therefore advisable to wrap a BufferedReader around any Reader whose read() operations may be costly, such as FileReaders and InputStreamReaders. For example,
BufferedReader in = new BufferedReader(new FileReader("foo.in"));will buffer the input from the specified file. Without buffering, each invocation of read() or readLine() could cause bytes to be read from the file, converted into characters, and then returned, which can be very inefficient.
Programs that use DataInputStreams for textual input can be localized by replacing each DataInputStream with an appropriate BufferedReader.
Field Summary |
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Fields inherited from class java.io. Reader |
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lock |
Constructor Summary | |
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BufferedReader
(
Reader
in) Create a buffering character-input stream that uses a default-sized input buffer. |
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BufferedReader
(
Reader
in, int sz) Create a buffering character-input stream that uses an input buffer of the specified size. |
Method Summary | |
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void |
close
() Close the stream. |
void |
mark
(int readAheadLimit) Mark the present position in the stream. |
boolean |
markSupported
() Tell whether this stream supports the mark() operation, which it does. |
int |
read
() Read a single character. |
int |
read
(char[] cbuf, int off, int len) Read characters into a portion of an array. |
String |
readLine
() Read a line of text. |
boolean |
ready
() Tell whether this stream is ready to be read. |
void |
reset
() Reset the stream to the most recent mark. |
long |
skip
(long n) Skip characters. |
Methods inherited from class java.io. Reader |
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read , read |
Methods inherited from class java.lang. Object |
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clone , equals , finalize , getClass , hashCode , notify , notifyAll , toString , wait , wait , wait |
Constructor Detail |
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public BufferedReader(Reader in, int sz)
public BufferedReader(Reader in)
Method Detail |
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public int read() throws IOException
public int read(char[] cbuf, int off, int len) throws IOException
This method implements the general contract of the corresponding read method of the Reader class. As an additional convenience, it attempts to read as many characters as possible by repeatedly invoking the read method of the underlying stream. This iterated read continues until one of the following conditions becomes true:
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 BufferedReaders will not copy data unnecessarily.
public String readLine() throws IOException
public long skip(long n) throws IOException
public boolean ready() throws IOException
public boolean markSupported()
public void mark(int readAheadLimit) throws IOException
public void reset() throws IOException
public void close() throws IOException