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## org.basex.util
Class Num

    java.lang.Object
      org.basex.util.Num

    public final class Num

extends Object

This class provides operations to compress and decompress integer values in byte arrays to save memory.

Author:
  Workgroup DBIS, University of Konstanz 2005-10, ISC License, Christian Gruen

Method Summary
`static byte[]` | `add(byte[] array, int val)` Compresses and writes an integer value to the specified array and returns the array.
`static int` | `len(byte[] array, int val)` Returns integer length.
`static int` | `len(int v)` Returns the compressed length of the specified value.
`static byte[]` | `newNum(int val)` Creates a new number array.
`static byte[]` | `num(int val)` Creates a new number array.
`static int` | `read(byte[] array, int pos)` Reads and decompresses an integer value from the specified byte array.
`static int` | `size(byte[] array)` Returns the length of the specified array, stored in the first four bytes.
`static void` | `size(byte[] array, int len)` Writes the specified length in the first bytes of the specified array.

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

Method Detail

### newNum

    public static byte[] newNum(int val)

  Creates a new number array.

  Parameters:
    `val` - initial value to be stored
  Returns:
    new number array

### num

    public static byte[] num(int val)

  Creates a new number array.

  Parameters:
    `val` - initial value to be stored
  Returns:
    new number array

### add

    public static byte[] add(byte[] array,
                             int val)

  Compresses and writes an integer value to the specified array and returns the array.

  Parameters:
    `array` - array
    `val` - value to be written
  Returns:
    new array

### read

    public static int read(byte[] array,
                           int pos)

  Reads and decompresses an integer value from the specified byte array.

  Parameters:
    `array` - array
    `pos` - position to parse
  Returns:
    decompressed value

### size

    public static int size(byte[] array)

  Returns the length of the specified array, stored in the first four bytes.

  Parameters:
    `array` - array to be evaluated
  Returns:
    array length

### len

    public static int len(byte[] array,
                          int val)

  Returns integer length.

  Parameters:
    `array` - array
    `val` - integer value
  Returns:
    value length

### size

    public static void size(byte[] array,
                            int len)

  Writes the specified length in the first bytes of the specified array.

  Parameters:
    `array` - array
    `len` - new length

### len

    public static int len(int v)

  Returns the compressed length of the specified value.

  Parameters:
    `v` - integer value
  Returns:
    value length

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