com.helger.commons.io.stream

Class NonBlockingByteArrayInputStream

java.lang.Object

java.io.InputStream

com.helger.commons.io.stream.NonBlockingByteArrayInputStream

All Implemented Interfaces:

Closeable, Serializable, AutoCloseable

Direct Known Subclasses:

StringInputStream

public class NonBlockingByteArrayInputStream
extends InputStream
implements Serializable

A non-synchronized copy of the class ByteArrayInputStream.

Author:

Philip Helger

See Also:

ByteArrayInputStream, Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static boolean	DEFAULT_COPY_NEEDED
protected byte[]	m_aBuf An array of bytes that was provided by the creator of the stream.
protected int	m_nCount The index one greater than the last valid character in the input stream buffer.
protected int	m_nMark The currently marked position in the stream.
protected int	m_nPos The index of the next character to read from the input stream buffer.

Constructor Summary

Constructors

Constructor and Description
NonBlockingByteArrayInputStream(byte[] aBuf) Creates a NonBlockingByteArrayInputStream so that it uses buf as its buffer array.
NonBlockingByteArrayInputStream(byte[] aBuf, boolean bIsCopyNeeded) Creates a NonBlockingByteArrayInputStream so that it uses buf as its buffer array.
NonBlockingByteArrayInputStream(byte[] aBuf, int nOfs, int nLen) Creates NonBlockingByteArrayInputStream that uses aBuf as its buffer array.
NonBlockingByteArrayInputStream(byte[] aBuf, int nOfs, int nLen, boolean bIsCopyNeeded) Creates NonBlockingByteArrayInputStream that uses aBuf as its buffer array.

Method Summary

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 NonBlockingByteArrayInputStream has no effect.
int	getPosition()
boolean	isCopy()
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[] aBuf, int nOfs, int nLen) 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.

Methods inherited from class java.io.InputStream

read

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

DEFAULT_COPY_NEEDED

public static final boolean DEFAULT_COPY_NEEDED

See Also:

Constant Field Values

m_aBuf

protected byte[] m_aBuf

An array of bytes that was provided by the creator of the stream. Elements 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.

m_nPos

protected int m_nPos

The index of the next character to read from the input stream buffer. This value should always be nonnegative and not larger than the value of count. The next byte to be read from the input stream buffer will be buf[pos].

m_nMark

protected int m_nMark

The currently marked position in the stream. NonBlockingByteArrayInputStream objects are marked at position zero by default when constructed. They may be marked at another position within the buffer by the 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).

m_nCount

protected int m_nCount

The index one greater than the last valid character in the input stream buffer. This value should always be nonnegative and not larger than the length of buf. It is one greater than the position of the last byte within buf that can ever be read from the input stream buffer.

Constructor Detail

NonBlockingByteArrayInputStream

public NonBlockingByteArrayInputStream(@Nonnull
                                       byte[] aBuf)

Creates a NonBlockingByteArrayInputStream 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.

Parameters:

aBuf - the input buffer.

NonBlockingByteArrayInputStream

public NonBlockingByteArrayInputStream(@Nonnull
                                       byte[] aBuf,
                                       boolean bIsCopyNeeded)

Creates a NonBlockingByteArrayInputStream 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.

Parameters:

aBuf - the input buffer.

bIsCopyNeeded - true if the array should be copied, false if not.

NonBlockingByteArrayInputStream

public NonBlockingByteArrayInputStream(@Nonnull
                                       byte[] aBuf,
                                       @Nonnegative
                                       int nOfs,
                                       @Nonnegative
                                       int nLen)

Creates NonBlockingByteArrayInputStream that uses aBuf as its buffer array. The initial value of nOfs is offset and the initial value of m_nCount is the minimum of nOfs+nLen and aBuf.length. The buffer array is not copied. The buffer's mark is set to the specified offset.

Parameters:

aBuf - the input buffer.

nOfs - the offset in the buffer of the first byte to read.

nLen - the maximum number of bytes to read from the buffer.

NonBlockingByteArrayInputStream

public NonBlockingByteArrayInputStream(@Nonnull
                                       byte[] aBuf,
                                       @Nonnegative
                                       int nOfs,
                                       @Nonnegative
                                       int nLen,
                                       boolean bIsCopyNeeded)

Creates NonBlockingByteArrayInputStream that uses aBuf as its buffer array. The initial value of nOfs is offset and the initial value of m_nCount is the minimum of nOfs+nLen and aBuf.length. The buffer's mark is set to the specified offset.

Parameters:

aBuf - the input buffer.

nOfs - the offset in the buffer of the first byte to read.

nLen - the maximum number of bytes to read from the buffer.

bIsCopyNeeded - true if the provided byte array needs to be copied, false if not.

Method Detail

isCopy

public final boolean isCopy()

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 read method cannot block.

Specified by:

read in class InputStream

Returns:

the next byte of data, or -1 if the end of the stream has been reached.

read

public int read(byte[] aBuf,
                int nOfs,
                int nLen)

Reads up to 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.

Overrides:

read in class InputStream

Parameters:

aBuf - the buffer into which the data is read.

nOfs - the start offset in the destination array b

nLen - the maximum number of bytes read.

Returns:

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.

skip

public long skip(long n)

Skips 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.

Overrides:

skip in class InputStream

Parameters:

n - the number of bytes to be skipped.

Returns:

the actual number of bytes skipped.

available

public int available()

Returns the number of remaining bytes that can be read (or skipped over) from this input stream.

The value returned is count - pos, which is the number of bytes remaining to be read from the input buffer.

Overrides:

available in class InputStream

Returns:

the number of remaining bytes that can be read (or skipped over) from this input stream without blocking.

markSupported

public boolean markSupported()

Tests if this InputStream supports mark/reset. The markSupported method of NonBlockingByteArrayInputStream always returns true.

Overrides:

markSupported in class InputStream

Returns:

Always true

mark

public void mark(int readAheadLimit)

Set the current marked position in the stream. NonBlockingByteArrayInputStream objects are marked at position zero by default when constructed. They may be marked at another position within the buffer by this method.

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.

Overrides:

mark in class InputStream

reset

public void reset()

Resets the buffer to the marked position. The marked position is 0 unless another position was marked or an offset was specified in the constructor.

Overrides:

reset in class InputStream

close

public void close()

Closing a NonBlockingByteArrayInputStream has no effect. The methods in this class can be called after the stream has been closed without generating an IOException.

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Overrides:

close in class InputStream

getPosition

@Nonnegative
public int getPosition()

Returns:

The position where we are in the stream.