SuballocatedIntVector (HtmlUnit-XPath 3.9.0 API)

java.lang.Object
- org.htmlunit.xpath.xml.utils.SuballocatedIntVector

```
public class SuballocatedIntVector
extends Object
```
A very simple table that stores a list of int. Very similar API to our IntVector class (same API); different internal storage.
This version uses an array-of-arrays solution. Read/write access is thus a bit slower than the simple IntVector, and basic storage is a trifle higher due to the top-level array -- but appending is O(1) fast rather than O(N**2) slow, which will swamp those costs in situations where long vectors are being built up.
Known issues:
Some methods are private because they haven't yet been tested properly.
Retrieval performance is critical, since this is used at the core of the DTM model. (Append performance is almost as important.) That's pushing me toward just letting reads from unset indices throw exceptions or return stale data; safer behavior would have performance costs.

Field Summary

Fields
Modifier and Type	Field and Description
`protected int`	`m_blocksize` Size of blocks to allocate
`protected int[]`	`m_buildCache` "Shortcut" handle to most recently added row of m_map.
`protected int`	`m_buildCacheStartIndex`
`protected int`	`m_firstFree` Number of ints in array
`protected int[][]`	`m_map` Array of arrays of ints
`protected int[]`	`m_map0` "Shortcut" handle to m_map[0].
`protected int`	`m_MASK`
`protected int`	`m_numblocks` The number of blocks to (over)allocate by
`protected int`	`m_SHIFT` Bitwise addressing (much faster than div/remainder
`protected static int`	`NUMBLOCKS_DEFAULT` The default number of blocks to (over)allocate by

Constructor Summary

Constructors
Constructor and Description
`SuballocatedIntVector(int blocksize)` Construct a IntVector, using the given block size and the default number of blocks (32).
`SuballocatedIntVector(int blocksize, int numblocks)` Construct a IntVector, using the given block size and number of blocks.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`addElement(int value)` Append a int onto the vector.
`int`	`elementAt(int i)` Get the nth element.
`int`	`indexOf(int elem)` Searches for the first occurence of the given argument, beginning the search at index, and testing for equality using the equals method.
`int`	`indexOf(int elem, int index)` Searches for the first occurence of the given argument, beginning the search at index, and testing for equality using the equals method.
`void`	`setElementAt(int value, int at)` Sets the component at the specified index of this vector to be the specified object.
`int`	`size()` Get the length of the list.

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

- Field Detail
  - m_blocksize
```
protected final int m_blocksize
```
    Size of blocks to allocate
  - m_SHIFT
```
protected int m_SHIFT
```
    Bitwise addressing (much faster than div/remainder
  - m_MASK
```
protected final int m_MASK
```
  - NUMBLOCKS_DEFAULT
```
protected static final int NUMBLOCKS_DEFAULT
```
    The default number of blocks to (over)allocate by
    
    See Also:
    
    Constant Field Values
  - m_numblocks
```
protected final int m_numblocks
```
    The number of blocks to (over)allocate by
  - m_map
```
protected int[][] m_map
```
    Array of arrays of ints
  - m_firstFree
```
protected int m_firstFree
```
    Number of ints in array
  - m_map0
```
protected final int[] m_map0
```
    "Shortcut" handle to m_map[0]. Surprisingly helpful for short vectors.
  - m_buildCache
```
protected int[] m_buildCache
```
    "Shortcut" handle to most recently added row of m_map. Very helpful during construction.
  - m_buildCacheStartIndex
```
protected int m_buildCacheStartIndex
```
- Constructor Detail
  - SuballocatedIntVector
```
public SuballocatedIntVector(int blocksize,
                             int numblocks)
```
    Construct a IntVector, using the given block size and number of blocks. For efficiency, we will round the requested size off to a power of two.
    
    Parameters:
    
    blocksize - Size of block to allocate
    
    numblocks - Number of blocks to allocate
  - SuballocatedIntVector
```
public SuballocatedIntVector(int blocksize)
```
    Construct a IntVector, using the given block size and the default number of blocks (32).
    
    Parameters:
    
    blocksize - Size of block to allocate
- Method Detail
  - size
```
public int size()
```
    Get the length of the list.
    
    Returns:
    
    length of the list
  - addElement
```
public void addElement(int value)
```
    Append a int onto the vector.
    
    Parameters:
    
    value - Int to add to the list
  - setElementAt
```
public void setElementAt(int value,
                         int at)
```
    Sets the component at the specified index of this vector to be the specified object. The previous component at that position is discarded.
    The index must be a value greater than or equal to 0 and less than the current size of the vector.
    
    Parameters:
    
    value - object to set
    
    at - Index of where to set the object
  - elementAt
```
public int elementAt(int i)
```
    Get the nth element. This is often at the innermost loop of an application, so performance is critical.
    
    Parameters:
    
    i - index of value to get
    
    Returns:
    
    value at given index. If that value wasn't previously set, the result is undefined for performance reasons. It may throw an exception (see below), may return zero, or (if setSize has previously been used) may return stale data.
    
    Throws:
    
    ArrayIndexOutOfBoundsException - if the index was _clearly_ unreasonable (negative, or past the highest block).
    
    NullPointerException - if the index points to a block that could have existed (based on the highest index used) but has never had anything set into it. %REVIEW% Could add a catch to create the block in that case, or return 0. Try/Catch is _supposed_ to be nearly free when not thrown to. Do we believe that? Should we have a separate safeElementAt?
  - indexOf
```
public int indexOf(int elem,
                   int index)
```
    Searches for the first occurence of the given argument, beginning the search at index, and testing for equality using the equals method.
    
    Parameters:
    
    elem - object to look for
    
    index - Index of where to begin search
    
    Returns:
    
    the index of the first occurrence of the object argument in this vector at position index or later in the vector; returns -1 if the object is not found.
  - indexOf
```
public int indexOf(int elem)
```
    Searches for the first occurence of the given argument, beginning the search at index, and testing for equality using the equals method.
    
    Parameters:
    
    elem - object to look for
    
    Returns:
    
    the index of the first occurrence of the object argument in this vector at position index or later in the vector; returns -1 if the object is not found.

Class SuballocatedIntVector

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

m_blocksize

m_SHIFT

m_MASK

NUMBLOCKS_DEFAULT

m_numblocks

m_map

m_firstFree

m_map0

m_buildCache

m_buildCacheStartIndex

Constructor Detail

SuballocatedIntVector

SuballocatedIntVector

Method Detail

size

addElement

setElementAt

elementAt

indexOf

indexOf