Movatterモバイル変換

Class BufferedInputStream

java.lang.Object
- java.io.InputStream
- - java.io.FilterInputStream
  - - java.io.BufferedInputStream

All Implemented Interfaces:
Closeable,AutoCloseable
```
public classBufferedInputStreamextendsFilterInputStream
```
ABufferedInputStream adds functionality to another input stream-namely, the ability to buffer the input and to support themark andreset methods. When theBufferedInputStream is created, an internal buffer array is created. As bytes from the stream are read or skipped, the internal buffer is refilled as necessary from the contained input stream, many bytes at a time. Themark operation remembers a point in the input stream and thereset operation causes all the bytes read since the most recentmark operation to be reread before new bytes are taken from the contained input stream.
Since:
1.0

Field Summary

Fields
Modifier and Type	Field	Description
`protected byte[]`	`buf`	The internal buffer array where the data is stored.
`protected int`	`count`	The index one greater than the index of the last valid byte in the buffer.
`protected int`	`marklimit`	The maximum read ahead allowed after a call to the`mark` method before subsequent calls to the`reset` method fail.
`protected int`	`markpos`	The value of the`pos` field at the time the last`mark` method was called.
`protected int`	`pos`	The current position in the buffer.

Fields declared in class java.io.FilterInputStream
in

Constructor Summary

Constructors
Constructor	Description
`BufferedInputStream(InputStream in)`	Creates a`BufferedInputStream` and saves its argument, the input stream`in`, for later use.
`BufferedInputStream(InputStream in, int size)`	Creates a`BufferedInputStream` with the specified buffer size, and saves its argument, the input stream`in`, for later use.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`int`	`available()`	Returns an estimate of the number of bytes that can be read (or skipped over) from this input stream without blocking by the next invocation of a method for this input stream.
`void`	`close()`	Closes this input stream and releases any system resources associated with the stream.
`void`	`mark(int readlimit)`	See the general contract of the`mark` method of`InputStream`.
`boolean`	`markSupported()`	Tests if this input stream supports the`mark` and`reset` methods.
`int`	`read()`	See the general contract of the`read` method of`InputStream`.
`int`	`read(byte[] b, int off, int len)`	Reads bytes from this byte-input stream into the specified byte array, starting at the given offset.
`void`	`reset()`	See the general contract of the`reset` method of`InputStream`.
`long`	`skip(long n)`	See the general contract of the`skip` method of`InputStream`.

Methods declared in class java.io.FilterInputStream
read

Methods declared in class java.io.InputStream
nullInputStream,readAllBytes,readNBytes,readNBytes,transferTo

Methods declared in class java.lang.Object
clone,equals,finalize,getClass,hashCode,notify,notifyAll,toString,wait,wait,wait

- Field Detail
  - buf
```
protected volatile byte[] buf
```
    The internal buffer array where the data is stored. When necessary, it may be replaced by another array of a different size.
  - count
```
protected int count
```
    The index one greater than the index of the last valid byte in the buffer. This value is always in the range0 throughbuf.length; elementsbuf[0] throughbuf[count-1]contain buffered input data obtained from the underlying input stream.
  - pos
```
protected int pos
```
    The current position in the buffer. This is the index of the next character to be read from thebuf array.
    This value is always in the range0 throughcount. If it is less thancount, thenbuf[pos] is the next byte to be supplied as input; if it is equal tocount, then the nextread orskip operation will require more bytes to be read from the contained input stream.
    See Also:
    buf
  - markpos
```
protected int markpos
```
    The value of thepos field at the time the lastmark method was called.
    This value is always in the range-1 throughpos. If there is no marked position in the input stream, this field is-1. If there is a marked position in the input stream, thenbuf[markpos] is the first byte to be supplied as input after areset operation. Ifmarkpos is not-1, then all bytes from positionsbuf[markpos] throughbuf[pos-1] must remain in the buffer array (though they may be moved to another place in the buffer array, with suitable adjustments to the values ofcount,pos, andmarkpos); they may not be discarded unless and until the difference betweenpos andmarkpos exceedsmarklimit.
    See Also:
    mark(int),pos
  - marklimit
```
protected int marklimit
```
    The maximum read ahead allowed after a call to themark method before subsequent calls to thereset method fail. Whenever the difference betweenpos andmarkpos exceedsmarklimit, then the mark may be dropped by settingmarkpos to-1.
    See Also:
    mark(int),reset()
- Constructor Detail
  - BufferedInputStream
```
public BufferedInputStream(InputStream in)
```
    Creates aBufferedInputStream and saves its argument, the input streamin, for later use. An internal buffer array is created and stored inbuf.
    Parameters:
    in - the underlying input stream.
  - BufferedInputStream
```
public BufferedInputStream(InputStream in,                           int size)
```
    Creates aBufferedInputStream with the specified buffer size, and saves its argument, the input streamin, for later use. An internal buffer array of lengthsize is created and stored inbuf.
    Parameters:
    in - the underlying input stream.
    size - the buffer size.
    Throws:
    IllegalArgumentException - ifsize <= 0.
- Method Detail
  - read
```
public int read()         throwsIOException
```
    See the general contract of theread method ofInputStream.
    Overrides:
    read in class FilterInputStream
    Returns:
    the next byte of data, or-1 if the end of the stream is reached.
    Throws:
    IOException - if this input stream has been closed by invoking itsclose() method, or an I/O error occurs.
    See Also:
    FilterInputStream.in
  - read
```
public int read(byte[] b,                int off,                int len)         throwsIOException
```
    Reads bytes from this byte-input stream into the specified byte array, starting at the given offset.
    This method implements the general contract of the correspondingread method of theInputStream class. As an additional convenience, it attempts to read as many bytes as possible by repeatedly invoking theread method of the underlying stream. This iteratedread continues until one of the following conditions becomes true:
    The specified number of bytes have been read,
    Theread method of the underlying stream returns-1, indicating end-of-file, or
    Theavailable method of the underlying stream returns zero, indicating that further input requests would block.
    If the firstread on the underlying stream returns-1 to indicate end-of-file then this method returns-1. Otherwise this method returns the number of bytes actually read.
    Subclasses of this class are encouraged, but not required, to attempt to read as many bytes as possible in the same fashion.
    Overrides:
    read in class FilterInputStream
    Parameters:
    b - destination buffer.
    off - offset at which to start storing bytes.
    len - maximum number of bytes to read.
    Returns:
    the number of bytes read, or-1 if the end of the stream has been reached.
    Throws:
    IOException - if this input stream has been closed by invoking itsclose() method, or an I/O error occurs.
    See Also:
    FilterInputStream.in
  - skip
```
public long skip(long n)          throwsIOException
```
    See the general contract of theskip method ofInputStream.
    Overrides:
    skip in class FilterInputStream
    Parameters:
    n - the number of bytes to be skipped.
    Returns:
    the actual number of bytes skipped.
    Throws:
    IOException - if this input stream has been closed by invoking itsclose() method,in.skip(n) throws an IOException, or an I/O error occurs.
  - available
```
public int available()              throwsIOException
```
    Returns an estimate of the number of bytes that can be read (or skipped over) from this input stream without blocking by the next invocation of a method for this input stream. The next invocation might be the same thread or another thread. A single read or skip of this many bytes will not block, but may read or skip fewer bytes.
    This method returns the sum of the number of bytes remaining to be read in the buffer (count - pos) and the result of calling thein.available().
    Overrides:
    available in class FilterInputStream
    Returns:
    an estimate of the number of bytes that can be read (or skipped over) from this input stream without blocking.
    Throws:
    IOException - if this input stream has been closed by invoking itsclose() method, or an I/O error occurs.
  - mark
```
public void mark(int readlimit)
```
    See the general contract of themark method ofInputStream.
    Overrides:
    mark in class FilterInputStream
    Parameters:
    readlimit - the maximum limit of bytes that can be read before the mark position becomes invalid.
    See Also:
    reset()
  - reset
```
public void reset()           throwsIOException
```
    See the general contract of thereset method ofInputStream.
    Ifmarkpos is-1 (no mark has been set or the mark has been invalidated), anIOException is thrown. Otherwise,pos is set equal tomarkpos.
    Overrides:
    reset in class FilterInputStream
    Throws:
    IOException - if this stream has not been marked or, if the mark has been invalidated, or the stream has been closed by invoking itsclose() method, or an I/O error occurs.
    See Also:
    mark(int)
  - markSupported
```
public boolean markSupported()
```
    Tests if this input stream supports themark andreset methods. ThemarkSupported method ofBufferedInputStream returnstrue.
    Overrides:
    markSupported in class FilterInputStream
    Returns:
    aboolean indicating if this stream type supports themark andreset methods.
    See Also:
    InputStream.mark(int),InputStream.reset()
  - close
```
public void close()           throwsIOException
```
    Closes this input stream and releases any system resources associated with the stream. Once the stream has been closed, further read(), available(), reset(), or skip() invocations will throw an IOException. Closing a previously closed stream has no effect.
    Specified by:
    close in interface AutoCloseable
    Specified by:
    close in interface Closeable
    Overrides:
    close in class FilterInputStream
    Throws:
    IOException - if an I/O error occurs.
    See Also:
    FilterInputStream.in

Movatterモバイル変換

Class BufferedInputStream

Field Summary

Fields declared in class java.io.FilterInputStream

Constructor Summary

Method Summary

Methods declared in class java.io.FilterInputStream

Methods declared in class java.io.InputStream

Methods declared in class java.lang.Object

Field Detail

buf

count

pos

markpos

marklimit

Constructor Detail

BufferedInputStream

BufferedInputStream

Method Detail

read

read

skip

available

mark

reset

markSupported

close