Important: This class doesn't close the streams that were passed to it. Each stream should be closed by the caller after the ConcatInputStream instance is closed.
This stream takes multiple InputStreams during its construction, and it will iterate over them when read operations are performed.
When a reading operation is performed, the class will try to read from the first input stream. When a stream returns zero bytes from a read operation, the class will move to the next stream and try reading from that. This repeats until no more streams are available, in which case the class will return end of stream for the reading operations.
This input stream class is not thread safe.
| public | ConcatInputStream( Creates a new instance for the given input streams. |
| public | ConcatInputStream( Creates a new instance for the given input streams specified by an iterator. |
| public | ConcatInputStream( Creates a new instance for the given input streams. |
| public int | 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. |
| public void | close() Closes this input stream and releases any system resources associated
with the stream. |
| public int | read() Reads the next byte of data from the input stream. |
| public int | read( Reads up to len bytes of data from the input stream into
an array of bytes. |
| public long | skip( Skips over and discards n bytes of data from this input
stream. |
From: InputStream |
From: Object |
null InputStreams in the argument iterable will be skipped.
null.
null InputStreams in the argument iterator will be skipped.
null.Modifying the argument array externally may result in incorrect operation.
null InputStreams in the argument array will be skipped.
null. 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.
0 when
it reaches the end of the input stream. The close method of InputStream does
nothing.
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.
-1 if the end of the
stream is reached.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.
b
at which the data is written.-1 if there is no more data because the end of
the stream has been reached.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, the skip method for class InputStream always
returns 0, and no bytes are skipped. Subclasses may handle the negative
value differently.
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.