Base64InputStream
public
class
Base64InputStream
extends FilterInputStream
java.lang.Object | |||
↳ | java.io.InputStream | ||
↳ | java.io.FilterInputStream | ||
↳ | android.util.Base64InputStream |
An InputStream that does Base64 decoding on the data read through it.
Summary
Inherited fields |
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Public constructors | |
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Base64InputStream(InputStream in, int flags)
An InputStream that performs Base64 decoding on the data read from the wrapped stream. |
Public methods | |
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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 caller 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)
Marks the current position in this input stream. |
boolean
|
markSupported()
Tests if this input stream supports the |
int
|
read()
Reads the next byte of data from this input stream. |
int
|
read(byte[] b, int off, int len)
Reads up to |
void
|
reset()
Repositions this stream to the position at the time the
|
long
|
skip(long n)
Skips over and discards |
Inherited methods | |
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Public constructors
Base64InputStream
public Base64InputStream (InputStream in, int flags)
An InputStream that performs Base64 decoding on the data read from the wrapped stream.
Parameters | |
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in |
InputStream : the InputStream to read the source data from |
flags |
int : bit flags for controlling the decoder; see the
constants in Base64 |
Public methods
available
public 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 caller of a method for this input stream. The next caller 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 result of in
.available().
Returns | |
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int |
an estimate of the number of bytes that can be read (or skipped over) from this input stream without blocking. |
close
public void close ()
Closes this input stream and releases any system resources
associated with the stream.
This
method simply performs in.close()
.
Throws | |
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IOException |
mark
public void mark (int readlimit)
Marks the current position in this input stream. A subsequent
call to the reset
method repositions this stream at
the last marked position so that subsequent reads re-read the same bytes.
The readlimit
argument tells this input stream to
allow that many bytes to be read before the mark position gets
invalidated.
This method simply performs in.mark(readlimit)
.
Parameters | |
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readlimit |
int : the maximum limit of bytes that can be read before
the mark position becomes invalid. |
markSupported
public boolean markSupported ()
Tests if this input stream supports the mark
and reset
methods.
This method
simply performs in.markSupported()
.
Returns | |
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boolean |
true if this stream type supports the
mark and reset method;
false otherwise. |
read
public int read ()
Reads the next byte of data from this input stream. The value
byte is returned as an 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.
This method
simply performs in.read()
and returns the result.
Returns | |
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int |
the next byte of data, or -1 if the end of the
stream is reached. |
Throws | |
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IOException |
read
public int read (byte[] b, int off, int len)
Reads up to len
bytes of data from this input stream
into an array of bytes. If len
is not zero, the method
blocks until some input is available; otherwise, no
bytes are read and 0
is returned.
This method simply performs in.read(b, off, len)
and returns the result.
Parameters | |
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b |
byte : the buffer into which the data is read. |
off |
int : the start offset in the destination array b |
len |
int : the maximum number of bytes read. |
Returns | |
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int |
the total number of bytes read into the buffer, or
-1 if there is no more data because the end of
the stream has been reached. |
Throws | |
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IOException |
reset
public void reset ()
Repositions this stream to the position at the time the
mark
method was last called on this input stream.
This method
simply performs in.reset()
.
Stream marks are intended to be used in situations where you need to read ahead a little to see what's in the stream. Often this is most easily done by invoking some general parser. If the stream is of the type handled by the parse, it just chugs along happily. If the stream is not of that type, the parser should toss an exception when it fails. If this happens within readlimit bytes, it allows the outer code to reset the stream and try another parser.
skip
public long skip (long n)
Skips over and discards n
bytes of data from the
input stream. The skip
method may, for a variety of
reasons, end up skipping over some smaller number of bytes,
possibly 0
. The actual number of bytes skipped is
returned.
This method simply performs in.skip(n)
.
Parameters | |
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n |
long : the number of bytes to be skipped. |
Returns | |
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long |
the actual number of bytes skipped. |
Throws | |
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IOException |