ByteArrayUtil (ELKI: Environment for DeveLoping KDD-Applications Supported by Index-Structures)

java.lang.Object
- de.lmu.ifi.dbs.elki.persistent.ByteArrayUtil

```
public final class ByteArrayUtil
extends Object
```
Class with various utilities for manipulating byte arrays. If you find a reusable copy of this in the Java API, please tell me. Using a ByteArrayOutputStream and DataInputStream doesn't seem appropriate. C.f. DataOutputStream and ByteArrayOutputStream

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`static class`	`ByteArrayUtil.ByteSerializer` Serializer for byte objects
`static class`	`ByteArrayUtil.DoubleSerializer` Serializer for double objects
`static class`	`ByteArrayUtil.FloatSerializer` Serializer for float objects
`static class`	`ByteArrayUtil.IntegerSerializer` Serializer for integer objects
`static class`	`ByteArrayUtil.LongSerializer` Serializer for long objects
`static class`	`ByteArrayUtil.ShortSerializer` Serializer for short objects
`static class`	`ByteArrayUtil.StringSerializer` Serializer for String objects
`static class`	`ByteArrayUtil.VarintSerializer` Serializer for Integer objects using a variable size encoding

Field Summary

Fields
Modifier and Type	Field and Description
`static ByteArrayUtil.ByteSerializer`	`BYTE_SERIALIZER` Static instance.
`static ByteArrayUtil.DoubleSerializer`	`DOUBLE_SERIALIZER` Static instance.
`static ByteArrayUtil.FloatSerializer`	`FLOAT_SERIALIZER` Static instance.
`static ByteArrayUtil.IntegerSerializer`	`INT_SERIALIZER` Static instance.
`static ByteArrayUtil.LongSerializer`	`LONG_SERIALIZER` Static instance.
`static ByteArrayUtil.ShortSerializer`	`SHORT_SERIALIZER` Static instance.
`static int`	`SIZE_BYTE` Size of a byte in bytes.
`static int`	`SIZE_DOUBLE` Size of a double in bytes.
`static int`	`SIZE_FLOAT` Size of a float in bytes.
`static int`	`SIZE_INT` Size of an integer in bytes.
`static int`	`SIZE_LONG` Size of a long in bytes.
`static int`	`SIZE_SHORT` Size of a short in bytes.
`static ByteArrayUtil.StringSerializer`	`STRING_SERIALIZER` Static instance.
`static ByteArrayUtil.VarintSerializer`	`VARINT_SERIALIZER` Static instance.

Constructor Summary

Constructors
Constructor and Description

ByteArrayUtil()

Constructors
Constructor and Description
`ByteArrayUtil()`

Method Summary

Methods
Modifier and Type	Method and Description
`static int`	`getSignedVarintLongSize(long val)` Compute the size of the varint encoding for this signed integer
`static int`	`getSignedVarintSize(int val)` Compute the size of the varint encoding for this signed integer
`static int`	`getUnsignedVarintLongSize(long obj)` Compute the size of the varint encoding for this unsigned integer
`static int`	`getUnsignedVarintSize(int obj)` Compute the size of the varint encoding for this unsigned integer
`static double`	`readDouble(byte[] array, int offset)` Read a double from the byte array at the given offset.
`static float`	`readFloat(byte[] array, int offset)` Read a float from the byte array at the given offset.
`static int`	`readInt(byte[] array, int offset)` Read an integer from the byte array at the given offset.
`static long`	`readLong(byte[] array, int offset)` Read a long from the byte array at the given offset.
`static short`	`readShort(byte[] array, int offset)` Read a short from the byte array at the given offset.
`static int`	`readSignedVarint(ByteBuffer buffer)` Read a signed integer.
`static long`	`readSignedVarintLong(ByteBuffer buffer)` Read a signed long.
`static int`	`readUnsignedShort(byte[] array, int offset)` Read an unsigned short from the byte array at the given offset.
`static int`	`readUnsignedVarint(ByteBuffer buffer)` Read an unsigned integer.
`static long`	`readUnsignedVarintLong(ByteBuffer buffer)` Read an unsigned long.
`static void`	`unmapByteBuffer(MappedByteBuffer map)` Unmap a byte buffer.
`static int`	`writeDouble(byte[] array, int offset, double v)` Write a double to the byte array at the given offset.
`static int`	`writeFloat(byte[] array, int offset, float v)` Write a float to the byte array at the given offset.
`static int`	`writeInt(byte[] array, int offset, int v)` Write an integer to the byte array at the given offset.
`static int`	`writeLong(byte[] array, int offset, long v)` Write a long to the byte array at the given offset.
`static int`	`writeShort(byte[] array, int offset, int v)` Write a short to the byte array at the given offset.
`static void`	`writeSignedVarint(ByteBuffer buffer, int val)` Write an signed integer using a variable-length encoding.
`static void`	`writeSignedVarintLong(ByteBuffer buffer, long val)` Write a signed long using a variable-length encoding.
`static void`	`writeUnsignedVarint(ByteBuffer buffer, int val)` Write an unsigned integer using a variable-length encoding.
`static void`	`writeUnsignedVarintLong(ByteBuffer buffer, long val)` Write an unsigned long using a variable-length encoding.

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

- Field Detail
  - SIZE_BYTE
```
public static final int SIZE_BYTE
```
    Size of a byte in bytes.
    
    See Also:
    Constant Field Values
  - SIZE_SHORT
```
public static final int SIZE_SHORT
```
    Size of a short in bytes.
    
    See Also:
    Constant Field Values
  - SIZE_INT
```
public static final int SIZE_INT
```
    Size of an integer in bytes.
    
    See Also:
    Constant Field Values
  - SIZE_LONG
```
public static final int SIZE_LONG
```
    Size of a long in bytes.
    
    See Also:
    Constant Field Values
  - SIZE_FLOAT
```
public static final int SIZE_FLOAT
```
    Size of a float in bytes.
    
    See Also:
    Constant Field Values
  - SIZE_DOUBLE
```
public static final int SIZE_DOUBLE
```
    Size of a double in bytes.
    
    See Also:
    Constant Field Values
  - BYTE_SERIALIZER
```
public static final ByteArrayUtil.ByteSerializer BYTE_SERIALIZER
```
    Static instance.
  - SHORT_SERIALIZER
```
public static final ByteArrayUtil.ShortSerializer SHORT_SERIALIZER
```
    Static instance.
  - INT_SERIALIZER
```
public static final ByteArrayUtil.IntegerSerializer INT_SERIALIZER
```
    Static instance.
  - LONG_SERIALIZER
```
public static final ByteArrayUtil.LongSerializer LONG_SERIALIZER
```
    Static instance.
  - FLOAT_SERIALIZER
```
public static final ByteArrayUtil.FloatSerializer FLOAT_SERIALIZER
```
    Static instance.
  - DOUBLE_SERIALIZER
```
public static final ByteArrayUtil.DoubleSerializer DOUBLE_SERIALIZER
```
    Static instance.
  - STRING_SERIALIZER
```
public static final ByteArrayUtil.StringSerializer STRING_SERIALIZER
```
    Static instance.
  - VARINT_SERIALIZER
```
public static final ByteArrayUtil.VarintSerializer VARINT_SERIALIZER
```
    Static instance.
- Constructor Detail
  - ByteArrayUtil
```
public ByteArrayUtil()
```
- Method Detail
  - writeShort
```
public static final int writeShort(byte[] array,
             int offset,
             int v)
```
    Write a short to the byte array at the given offset.
    
    Parameters:
    array - Array to write to
    offset - Offset to write to
    v - data
    
    Returns:
    number of bytes written
  - writeInt
```
public static final int writeInt(byte[] array,
           int offset,
           int v)
```
    Write an integer to the byte array at the given offset.
    
    Parameters:
    array - Array to write to
    offset - Offset to write to
    v - data
    
    Returns:
    number of bytes written
  - writeLong
```
public static final int writeLong(byte[] array,
            int offset,
            long v)
```
    Write a long to the byte array at the given offset.
    
    Parameters:
    array - Array to write to
    offset - Offset to write to
    v - data
    
    Returns:
    number of bytes written
  - writeFloat
```
public static final int writeFloat(byte[] array,
             int offset,
             float v)
```
    Write a float to the byte array at the given offset.
    
    Parameters:
    array - Array to write to
    offset - Offset to write to
    v - data
    
    Returns:
    number of bytes written
  - writeDouble
```
public static final int writeDouble(byte[] array,
              int offset,
              double v)
```
    Write a double to the byte array at the given offset.
    
    Parameters:
    array - Array to write to
    offset - Offset to write to
    v - data
    
    Returns:
    number of bytes written
  - readShort
```
public static final short readShort(byte[] array,
              int offset)
```
    Read a short from the byte array at the given offset.
    
    Parameters:
    array - Array to read from
    offset - Offset to read at
    
    Returns:
    (signed) short
  - readUnsignedShort
```
public static final int readUnsignedShort(byte[] array,
                    int offset)
```
    Read an unsigned short from the byte array at the given offset.
    
    Parameters:
    array - Array to read from
    offset - Offset to read at
    
    Returns:
    short
  - readInt
```
public static final int readInt(byte[] array,
          int offset)
```
    Read an integer from the byte array at the given offset.
    
    Parameters:
    array - Array to read from
    offset - Offset to read at
    
    Returns:
    data
  - readLong
```
public static final long readLong(byte[] array,
            int offset)
```
    Read a long from the byte array at the given offset.
    
    Parameters:
    array - Array to read from
    offset - Offset to read at
    
    Returns:
    data
  - readFloat
```
public static final float readFloat(byte[] array,
              int offset)
```
    Read a float from the byte array at the given offset.
    
    Parameters:
    array - Array to read from
    offset - Offset to read at
    
    Returns:
    data
  - readDouble
```
public static final double readDouble(byte[] array,
                int offset)
```
    Read a double from the byte array at the given offset.
    
    Parameters:
    array - Array to read from
    offset - Offset to read at
    
    Returns:
    data
  - writeSignedVarint
```
public static final void writeSignedVarint(ByteBuffer buffer,
                     int val)
```
    Write an signed integer using a variable-length encoding. The sign bit is moved to bit 0. Data is always written in 7-bit little-endian, where the 8th bit is the continuation flag.
    
    Parameters:
    buffer - Buffer to write to
    val - number to write
  - writeSignedVarintLong
```
public static final void writeSignedVarintLong(ByteBuffer buffer,
                         long val)
```
    Write a signed long using a variable-length encoding. The sign bit is moved to bit 0. Data is always written in 7-bit little-endian, where the 8th bit is the continuation flag.
    
    Parameters:
    buffer - Buffer to write to
    val - number to write
  - writeUnsignedVarint
```
public static final void writeUnsignedVarint(ByteBuffer buffer,
                       int val)
```
    Write an unsigned integer using a variable-length encoding. Data is always written in 7-bit little-endian, where the 8th bit is the continuation flag.
    
    Parameters:
    buffer - Buffer to write to
    val - number to write
  - writeUnsignedVarintLong
```
public static final void writeUnsignedVarintLong(ByteBuffer buffer,
                           long val)
```
    Write an unsigned long using a variable-length encoding. Data is always written in 7-bit little-endian, where the 8th bit is the continuation flag. Note that for integers, this will result in the same encoding as writeUnsignedVarint(java.nio.ByteBuffer, int)
    
    Parameters:
    buffer - Buffer to write to
    val - number to write
  - getSignedVarintSize
```
public static final int getSignedVarintSize(int val)
```
    Compute the size of the varint encoding for this signed integer
    
    Parameters:
    val - integer to write
    
    Returns:
    Encoding size of this integer
  - getUnsignedVarintSize
```
public static final int getUnsignedVarintSize(int obj)
```
    Compute the size of the varint encoding for this unsigned integer
    
    Parameters:
    obj - integer to write
    
    Returns:
    Encoding size of this integer
  - getSignedVarintLongSize
```
public static final int getSignedVarintLongSize(long val)
```
    Compute the size of the varint encoding for this signed integer
    
    Parameters:
    val - integer to write
    
    Returns:
    Encoding size of this integer
  - getUnsignedVarintLongSize
```
public static final int getUnsignedVarintLongSize(long obj)
```
    Compute the size of the varint encoding for this unsigned integer
    
    Parameters:
    obj - integer to write
    
    Returns:
    Encoding size of this integer
  - readSignedVarint
```
public static final int readSignedVarint(ByteBuffer buffer)
```
    Read a signed integer.
    
    Parameters:
    buffer - Buffer to read from
    
    Returns:
    Integer value
  - readUnsignedVarint
```
public static final int readUnsignedVarint(ByteBuffer buffer)
```
    Read an unsigned integer.
    
    Parameters:
    buffer - Buffer to read from
    
    Returns:
    Integer value
  - readSignedVarintLong
```
public static final long readSignedVarintLong(ByteBuffer buffer)
```
    Read a signed long.
    
    Parameters:
    buffer - Buffer to read from
    
    Returns:
    long value
  - readUnsignedVarintLong
```
public static final long readUnsignedVarintLong(ByteBuffer buffer)
```
    Read an unsigned long.
    
    Parameters:
    buffer - Buffer to read from
    
    Returns:
    long value
  - unmapByteBuffer
```
public static void unmapByteBuffer(MappedByteBuffer map)
```
    Unmap a byte buffer.
    
    Parameters:
    map - Byte buffer to unmap.

Class ByteArrayUtil

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

SIZE_BYTE

SIZE_SHORT

SIZE_INT

SIZE_LONG

SIZE_FLOAT

SIZE_DOUBLE

BYTE_SERIALIZER

SHORT_SERIALIZER

INT_SERIALIZER

LONG_SERIALIZER

FLOAT_SERIALIZER

DOUBLE_SERIALIZER

STRING_SERIALIZER

VARINT_SERIALIZER

Constructor Detail

ByteArrayUtil

Method Detail

writeShort

writeInt

writeLong

writeFloat

writeDouble

readShort

readUnsignedShort

readInt

readLong

readFloat

readDouble

writeSignedVarint

writeSignedVarintLong

writeUnsignedVarint

writeUnsignedVarintLong

getSignedVarintSize

getUnsignedVarintSize

getSignedVarintLongSize

getUnsignedVarintLongSize

readSignedVarint

readUnsignedVarint

readSignedVarintLong

readUnsignedVarintLong

unmapByteBuffer