ByteBufferUtils (Apache HBase 1.2.12 API)

java.lang.Object
- org.apache.hadoop.hbase.util.ByteBufferUtils

@InterfaceAudience.Public
@InterfaceStability.Evolving
public final class ByteBufferUtils
extends Object

Utility functions for working with byte buffers, such as reading/writing variable-length long numbers.

Method Summary

Methods
Modifier and Type	Method and Description
`static boolean`	`arePartsEqual(ByteBuffer buffer, int offsetLeft, int lengthLeft, int offsetRight, int lengthRight)` Check whether two parts in the same buffer are equal.
`static int`	`compareTo(ByteBuffer buf1, int o1, int len1, ByteBuffer buf2, int o2, int len2)`
`static void`	`copyBufferToStream(OutputStream out, ByteBuffer in, int offset, int length)` Copy data from a buffer to an output stream.
`static void`	`copyFromBufferToBuffer(ByteBuffer out, ByteBuffer in, int sourceOffset, int length)` Copy from one buffer to another from given offset.
`static void`	`copyFromBufferToBuffer(ByteBuffer out, ByteBuffer in, int sourceOffset, int destinationOffset, int length)` Copy from one buffer to another from given offset.
`static void`	`copyFromStreamToBuffer(ByteBuffer out, DataInputStream in, int length)` Copy the given number of bytes from the given stream and put it at the current position of the given buffer, updating the position in the buffer.
`static ByteBuffer`	`drainInputStreamToBuffer(InputStream is)` Copy from the InputStream to a new heap ByteBuffer until the InputStream is exhausted.
`static void`	`extendLimit(ByteBuffer buffer, int numBytes)`
`static int`	`findCommonPrefix(byte[] left, int leftOffset, int leftLength, byte[] right, int rightOffset, int rightLength)` Find length of common prefix in two arrays.
`static int`	`findCommonPrefix(ByteBuffer buffer, int offsetLeft, int offsetRight, int limit)` Find length of common prefix of two parts in the buffer
`static int`	`intFitsIn(int value)` Check how many bytes is required to store value.
`static int`	`longFitsIn(long value)` Check how many bytes are required to store value.
`static void`	`moveBufferToStream(OutputStream out, ByteBuffer in, int length)` Copy the data to the output stream and update position in buffer.
`static int`	`putCompressedInt(OutputStream out, int value)` Put in buffer integer using 7 bit encoding.
`static void`	`putInt(OutputStream out, int value)` Put in output stream 32 bit integer (Big Endian byte order).
`static int`	`putLong(OutputStream out, long value, int fitInBytes)`
`static int`	`readCompressedInt(ByteBuffer buffer)` Read integer from buffer coded in 7 bits and increment position.
`static int`	`readCompressedInt(InputStream input)` Read integer from stream coded in 7 bits and increment position.
`static long`	`readLong(ByteBuffer in, int fitInBytes)` Read long which was written to fitInBytes bytes and increment position.
`static long`	`readLong(InputStream in, int fitInBytes)` Read long which was written to fitInBytes bytes and increment position.
`static long`	`readVLong(ByteBuffer in)` Similar to `WritableUtils.readVLong(DataInput)` but reads from a `ByteBuffer`.
`static void`	`skip(ByteBuffer buffer, int length)` Increment position in buffer.
`static byte[]`	`toBytes(ByteBuffer buffer, int startPosition)` Copy the bytes from position to limit into a new byte[] of the exact length and sets the position and limit back to their original values (though not thread safe).
`static byte[]`	`toBytes(ByteBuffer buffer, int offset, int length)` Copy the given number of bytes from specified offset into a new byte[]
`static void`	`writeVLong(ByteBuffer out, long i)` Similar to `WritableUtils.writeVLong(java.io.DataOutput, long)`, but writes to a `ByteBuffer`.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Method Detail
  - writeVLong
```
public static void writeVLong(ByteBuffer out,
              long i)
```
    Similar to WritableUtils.writeVLong(java.io.DataOutput, long), but writes to a ByteBuffer.
  - readVLong
```
public static long readVLong(ByteBuffer in)
```
    Similar to WritableUtils.readVLong(DataInput) but reads from a ByteBuffer.
  - putCompressedInt
```
public static int putCompressedInt(OutputStream out,
                   int value)
                            throws IOException
```
    Put in buffer integer using 7 bit encoding. For each written byte: 7 bits are used to store value 1 bit is used to indicate whether there is next bit.
    
    Parameters:
    value - Int to be compressed.
    out - Where to put compressed data
    
    Returns:
    Number of bytes written.
    
    Throws:
    
    IOException - on stream error
  - putInt
```
public static void putInt(OutputStream out,
          int value)
                   throws IOException
```
    Put in output stream 32 bit integer (Big Endian byte order).
    
    Parameters:
    out - Where to put integer.
    value - Value of integer.
    
    Throws:
    
    IOException - On stream error.
  - moveBufferToStream
```
public static void moveBufferToStream(OutputStream out,
                      ByteBuffer in,
                      int length)
                               throws IOException
```
    Copy the data to the output stream and update position in buffer.
    
    Parameters:
    out - the stream to write bytes to
    in - the buffer to read bytes from
    length - the number of bytes to copy
    
    Throws:
    
    IOException
  - copyBufferToStream
```
public static void copyBufferToStream(OutputStream out,
                      ByteBuffer in,
                      int offset,
                      int length)
                               throws IOException
```
    Copy data from a buffer to an output stream. Does not update the position in the buffer.
    
    Parameters:
    out - the stream to write bytes to
    in - the buffer to read bytes from
    offset - the offset in the buffer (from the buffer's array offset) to start copying bytes from
    length - the number of bytes to copy
    
    Throws:
    
    IOException
  - putLong
```
public static int putLong(OutputStream out,
          long value,
          int fitInBytes)
                   throws IOException
```
    Throws:
    
    IOException
  - longFitsIn
```
public static int longFitsIn(long value)
```
    Check how many bytes are required to store value.
    
    Parameters:
    value - Value which size will be tested.
    
    Returns:
    How many bytes are required to store value.
  - intFitsIn
```
public static int intFitsIn(int value)
```
    Check how many bytes is required to store value.
    
    Parameters:
    value - Value which size will be tested.
    
    Returns:
    How many bytes are required to store value.
  - readCompressedInt
```
public static int readCompressedInt(InputStream input)
                             throws IOException
```
    Read integer from stream coded in 7 bits and increment position.
    
    Returns:
    the integer that has been read
    
    Throws:
    
    IOException
  - readCompressedInt
```
public static int readCompressedInt(ByteBuffer buffer)
```
    Read integer from buffer coded in 7 bits and increment position.
    
    Returns:
    Read integer.
  - readLong
```
public static long readLong(InputStream in,
            int fitInBytes)
                     throws IOException
```
    Read long which was written to fitInBytes bytes and increment position.
    
    Parameters:
    fitInBytes - In how many bytes given long is stored.
    
    Returns:
    The value of parsed long.
    
    Throws:
    
    IOException
  - readLong
```
public static long readLong(ByteBuffer in,
            int fitInBytes)
```
    Read long which was written to fitInBytes bytes and increment position.
    
    Parameters:
    fitInBytes - In how many bytes given long is stored.
    
    Returns:
    The value of parsed long.
  - copyFromStreamToBuffer
```
public static void copyFromStreamToBuffer(ByteBuffer out,
                          DataInputStream in,
                          int length)
                                   throws IOException
```
    Copy the given number of bytes from the given stream and put it at the current position of the given buffer, updating the position in the buffer.
    
    Parameters:
    out - the buffer to write data to
    in - the stream to read data from
    length - the number of bytes to read/write
    
    Throws:
    
    IOException
  - drainInputStreamToBuffer
```
public static ByteBuffer drainInputStreamToBuffer(InputStream is)
                                           throws IOException
```
    Copy from the InputStream to a new heap ByteBuffer until the InputStream is exhausted.
    
    Throws:
    
    IOException
  - copyFromBufferToBuffer
```
public static void copyFromBufferToBuffer(ByteBuffer out,
                          ByteBuffer in,
                          int sourceOffset,
                          int length)
```
    Copy from one buffer to another from given offset.
    Note : This will advance the position marker of out but not change the position maker for in
    
    Parameters:
    out - destination buffer
    in - source buffer
    sourceOffset - offset in the source buffer
    length - how many bytes to copy
  - copyFromBufferToBuffer
```
public static void copyFromBufferToBuffer(ByteBuffer out,
                          ByteBuffer in,
                          int sourceOffset,
                          int destinationOffset,
                          int length)
```
    Copy from one buffer to another from given offset. This will be absolute positional copying and won't affect the position of any of the buffers.
    
    Parameters:
    out -
    in -
    sourceOffset -
    destinationOffset -
    length -
  - findCommonPrefix
```
public static int findCommonPrefix(ByteBuffer buffer,
                   int offsetLeft,
                   int offsetRight,
                   int limit)
```
    Find length of common prefix of two parts in the buffer
    
    Parameters:
    buffer - Where parts are located.
    offsetLeft - Offset of the first part.
    offsetRight - Offset of the second part.
    limit - Maximal length of common prefix.
    
    Returns:
    Length of prefix.
  - findCommonPrefix
```
public static int findCommonPrefix(byte[] left,
                   int leftOffset,
                   int leftLength,
                   byte[] right,
                   int rightOffset,
                   int rightLength)
```
    Find length of common prefix in two arrays.
    
    Parameters:
    left - Array to be compared.
    leftOffset - Offset in left array.
    leftLength - Length of left array.
    right - Array to be compared.
    rightOffset - Offset in right array.
    rightLength - Length of right array.
  - arePartsEqual
```
public static boolean arePartsEqual(ByteBuffer buffer,
                    int offsetLeft,
                    int lengthLeft,
                    int offsetRight,
                    int lengthRight)
```
    Check whether two parts in the same buffer are equal.
    
    Parameters:
    buffer - In which buffer there are parts
    offsetLeft - Beginning of first part.
    lengthLeft - Length of the first part.
    offsetRight - Beginning of the second part.
    lengthRight - Length of the second part.
    
    Returns:
    True if equal
  - skip
```
public static void skip(ByteBuffer buffer,
        int length)
```
    Increment position in buffer.
    
    Parameters:
    buffer - In this buffer.
    length - By that many bytes.
  - extendLimit
```
public static void extendLimit(ByteBuffer buffer,
               int numBytes)
```
  - toBytes
```
public static byte[] toBytes(ByteBuffer buffer,
             int startPosition)
```
    Copy the bytes from position to limit into a new byte[] of the exact length and sets the position and limit back to their original values (though not thread safe).
    
    Parameters:
    buffer - copy from here
    startPosition - put buffer.get(startPosition) into byte[0]
    
    Returns:
    a new byte[] containing the bytes in the specified range
  - toBytes
```
public static byte[] toBytes(ByteBuffer buffer,
             int offset,
             int length)
```
    Copy the given number of bytes from specified offset into a new byte[]
    
    Parameters:
    buffer -
    offset -
    length -
    
    Returns:
    a new byte[] containing the bytes in the specified range
  - compareTo
```
public static int compareTo(ByteBuffer buf1,
            int o1,
            int len1,
            ByteBuffer buf2,
            int o2,
            int len2)
```

Class ByteBufferUtils

Method Summary

Methods inherited from class java.lang.Object

Method Detail

writeVLong

readVLong

putCompressedInt

putInt

moveBufferToStream

copyBufferToStream

putLong

longFitsIn

intFitsIn

readCompressedInt

readCompressedInt

readLong

readLong

copyFromStreamToBuffer

drainInputStreamToBuffer

copyFromBufferToBuffer

copyFromBufferToBuffer

findCommonPrefix

findCommonPrefix

arePartsEqual

skip

extendLimit

toBytes

toBytes

compareTo