public class ByteArrayInputStream extends InputStream
ByteArrayInputStream contains an internal buffer that contains bytes that may be read from the stream. An internal counter keeps track of the next byte to be supplied by the
read method.
Closing a ByteArrayInputStream has no effect. The methods in this class can be called after the stream has been closed without generating an IOException.
StringBufferInputStream
| Modifier and Type | Field and Description |
|---|---|
protected byte[] |
buf
An array of bytes that was provided by the creator of the stream.
|
protected int |
count
The index one greater than the last valid character in the input stream buffer.
|
protected int |
mark
The currently marked position in the stream.
|
protected int |
pos
The index of the next character to read from the input stream buffer.
|
| Constructor and Description |
|---|
ByteArrayInputStream(byte[] buf)
Creates a
ByteArrayInputStream so that it uses
buf as its buffer array.
|
ByteArrayInputStream(byte[] buf, int offset, int length)
Creates
ByteArrayInputStream that uses
buf as its buffer array.
|
| Modifier and Type | Method and Description |
|---|---|
int |
available()
Returns the number of remaining bytes that can be read (or skipped over) from this input stream.
|
void |
close()
Closing a
ByteArrayInputStream has no effect.
|
void |
mark(int readAheadLimit)
Set the current marked position in the stream.
|
boolean |
markSupported()
Tests if this
InputStream supports mark/reset.
|
int |
read()
Reads the next byte of data from this input stream.
|
int |
read(byte[] b, int off, int len)
Reads up to
len bytes of data into an array of bytes from this input stream.
|
void |
reset()
Resets the buffer to the marked position.
|
long |
skip(long n)
Skips
n bytes of input from this input stream.
|
readprotected byte[] buf
buf[0] through
buf[count-1] are the only bytes that can ever be read from the stream; element
buf[pos] is the next byte to be read.
protected int pos
count. The next byte to be read from the input stream buffer will be
buf[pos].
protected int mark
mark() method. The current buffer position is set to this point by the
reset() method.
If no mark has been set, then the value of mark is the offset passed to the constructor (or 0 if the offset was not supplied).
protected int count
buf. It is one greater than the position of the last byte within
buf that can ever be read from the input stream buffer.
public ByteArrayInputStream(byte[] buf)
ByteArrayInputStream so that it uses
buf as its buffer array. The buffer array is not copied. The initial value of
pos is
0 and the initial value of
count is the length of
buf.
buf - the input buffer.
public ByteArrayInputStream(byte[] buf,
int offset,
int length)
ByteArrayInputStream that uses
buf as its buffer array. The initial value of
pos is
offset and the initial value of
count is the minimum of
offset+length and
buf.length. The buffer array is not copied. The buffer's mark is set to the specified offset.
buf - the input buffer.
offset - the offset in the buffer of the first byte to read.
length - the maximum number of bytes to read from the buffer.
public int read()
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 read method cannot block.
read in class
InputStream
-1 if the end of the stream has been reached.
public int read(byte[] b,
int off,
int len)
len bytes of data into an array of bytes from this input stream. If
pos equals
count, then
-1 is returned to indicate end of file. Otherwise, the number
k of bytes read is equal to the smaller of
len and
count-pos. If
k is positive, then bytes
buf[pos] through
buf[pos+k-1] are copied into
b[off] through
b[off+k-1] in the manner performed by
System.arraycopy. The value
k is added into
pos and
k is returned.
This read method cannot block.
read in class
InputStream
b - the buffer into which the data is read.
off - the start offset in the destination array
b
len - the maximum number of bytes read.
-1 if there is no more data because the end of the stream has been reached.
NullPointerException - If
b is
null.
IndexOutOfBoundsException - If
off is negative,
len is negative, or
len is greater than
b.length - off
InputStream.read()
public long skip(long n)
n bytes of input from this input stream. Fewer bytes might be skipped if the end of the input stream is reached. The actual number
k of bytes to be skipped is equal to the smaller of
n and
count-pos. The value
k is added into
pos and
k is returned.
skip in class
InputStream
n - the number of bytes to be skipped.
public int available()
The value returned is count - pos, which is the number of bytes remaining to be read from the input buffer.
available in class
InputStream
public boolean markSupported()
InputStream supports mark/reset. The
markSupported method of
ByteArrayInputStream always returns
true.
markSupported in class
InputStream
true if this stream instance supports the mark and reset methods;
false otherwise.
InputStream.mark(int) ,
InputStream.reset()
public void mark(int readAheadLimit)
If no mark has been set, then the value of the mark is the offset passed to the constructor (or 0 if the offset was not supplied).
Note: The readAheadLimit for this class has no meaning.
mark in class
InputStream
readAheadLimit - the maximum limit of bytes that can be read before the mark position becomes invalid.
InputStream.reset()
public void reset()
reset in class
InputStream
InputStream.mark(int) ,
IOException
public void close()
throws IOException
close in interface
Closeable
close in interface
AutoCloseable
close in class
InputStream
IOException - if an I/O error occurs.