public static class StrictJarFile.RAFStream extends InputStream
We could support mark/reset, but we don't currently need them.
Constructor and Description |
---|
RAFStream(RandomAccessFile raf,
long initialOffset) |
RAFStream(RandomAccessFile raf,
long initialOffset,
long endOffset) |
Modifier and Type | Method and 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.
|
int |
read()
Reads the next byte of data from the input stream.
|
int |
read(byte[] buffer,
int byteOffset,
int byteCount)
Reads up to
len bytes of data from the input stream into
an array of bytes. |
long |
skip(long byteCount)
Skips over and discards
n bytes of data from this input
stream. |
close, mark, markSupported, read, reset
public RAFStream(RandomAccessFile raf, long initialOffset, long endOffset)
public RAFStream(RandomAccessFile raf, long initialOffset) throws IOException
IOException
public int available() throws IOException
InputStream
Note that while some implementations of InputStream
will return
the total number of bytes in the stream, many will not. It is
never correct to use the return value of this method to allocate
a buffer intended to hold all data in this stream.
A subclass' implementation of this method may choose to throw an
IOException
if this input stream has been closed by
invoking the InputStream.close()
method.
The available
method for class InputStream
always
returns 0
.
This method should be overridden by subclasses.
available
in class InputStream
0
when
it reaches the end of the input stream.IOException
- if an I/O error occurs.public int read() throws IOException
InputStream
int
in the range 0
to
255
. If no byte is available because the end of the stream
has been reached, the value -1
is returned. This method
blocks until input data is available, the end of the stream is detected,
or an exception is thrown.
A subclass must provide an implementation of this method.
read
in class InputStream
-1
if the end of the
stream is reached.IOException
- if an I/O error occurs.public int read(byte[] buffer, int byteOffset, int byteCount) throws IOException
InputStream
len
bytes of data from the input stream into
an array of bytes. An attempt is made to read as many as
len
bytes, but a smaller number may be read.
The number of bytes actually read is returned as an integer.
This method blocks until input data is available, end of file is detected, or an exception is thrown.
If len
is zero, then no bytes are read and
0
is returned; otherwise, there is an attempt to read at
least one byte. If no byte is available because the stream is at end of
file, the value -1
is returned; otherwise, at least one
byte is read and stored into b
.
The first byte read is stored into element b[off]
, the
next one into b[off+1]
, and so on. The number of bytes read
is, at most, equal to len
. Let k be the number of
bytes actually read; these bytes will be stored in elements
b[off]
through b[off+
k-1]
,
leaving elements b[off+
k]
through
b[off+len-1]
unaffected.
In every case, elements b[0]
through
b[off]
and elements b[off+len]
through
b[b.length-1]
are unaffected.
The read(b,
off,
len)
method
for class InputStream
simply calls the method
read()
repeatedly. If the first such call results in an
IOException
, that exception is returned from the call to
the read(b,
off,
len)
method. If
any subsequent call to read()
results in a
IOException
, the exception is caught and treated as if it
were end of file; the bytes read up to that point are stored into
b
and the number of bytes read before the exception
occurred is returned. The default implementation of this method blocks
until the requested amount of input data len
has been read,
end of file is detected, or an exception is thrown. Subclasses are encouraged
to provide a more efficient implementation of this method.
read
in class InputStream
buffer
- the buffer into which the data is read.byteOffset
- the start offset in array b
at which the data is written.byteCount
- the maximum number of bytes to read.-1
if there is no more data because the end of
the stream has been reached.IOException
- If the first byte cannot be read for any reason
other than end of file, or if the input stream has been closed, or if
some other I/O error occurs.InputStream.read()
public long skip(long byteCount) throws IOException
InputStream
n
bytes of data from this input
stream. The skip
method may, for a variety of reasons, end
up skipping over some smaller number of bytes, possibly 0
.
This may result from any of a number of conditions; reaching end of file
before n
bytes have been skipped is only one possibility.
The actual number of bytes skipped is returned. If n
is
negative, no bytes are skipped.
The skip
method of this class creates a
byte array and then repeatedly reads into it until n
bytes
have been read or the end of the stream has been reached. Subclasses are
encouraged to provide a more efficient implementation of this method.
For instance, the implementation may depend on the ability to seek.
skip
in class InputStream
byteCount
- the number of bytes to be skipped.IOException
- if the stream does not support seek,
or if some other I/O error occurs.