Package org.magicwerk.brownies.collections.primitive

Class ShortBigList

java.lang.Object
org.magicwerk.brownies.collections.primitive.IShortList
org.magicwerk.brownies.collections.primitive.ShortBigList
All Implemented Interfaces:
Serializable, Cloneable, IShortListable
Direct Known Subclasses:
ShortBigList.ReadOnlyShortBigList
public class ShortBigList extends IShortList
ShortBigList is a list optimized for storing large number of elements. It stores the elements in fixed size blocks and the blocks itself are maintained in a tree for fast access. It also offers specialized methods for bulk processing of elements. Also copying a ShortBigList is efficiently possible as its implemented using a copy-on-write approach.

Note that this implementation is not synchronized. Due to data caching used for exploiting locality of reference, performance can decrease if ShortBigList is accessed by several threads at different positions.

Note that the iterators provided are not fail-fast.

See Also:

  • Field Details

    • serialVersionUID

      private static final long serialVersionUID
      UID for serialization
      See Also:

    • DEFAULT_BLOCK_SIZE

      private static final int DEFAULT_BLOCK_SIZE
      Default block size
      See Also:

    • MERGE_THRESHOLD

      private static final float MERGE_THRESHOLD
      If two adjacent blocks both less than MERGE_THRESHOLD*blockSize elements, they are merged
      See Also:

    • FILL_THRESHOLD

      private static final float FILL_THRESHOLD
      If an element is added to the list at the head or tail, the block is only filled until it has FILL_THRESHOLD*blockSize elements (so there is room for insertion without need to split).
      See Also:

    • CHECK

      private static final boolean CHECK
      Set to true for debugging during developing
      See Also:

    • EMPTY

      private static final ShortBigList EMPTY
      Unmodifiable empty instance

    • blockSize

      private int blockSize
      Number of elements stored at maximum in a block

    • size

      private int size
      Number of elements stored in this ShortBigList

    • rootNode

      private ShortBigList.ShortBlockNode rootNode
      The root node in the tree

    • currNode

      private ShortBigList.ShortBlockNode currNode
      Current node

    • currShortBlockStart

      private int currShortBlockStart
      Start index of current block

    • currShortBlockEnd

      private int currShortBlockEnd
      End index of current block

    • currModify

      private int currModify
      Modify value which must be applied before this block is not current any more

  • Constructor Details

    • ShortBigList

      protected ShortBigList(boolean copy, ShortBigList that)
      Constructor used internally, e.g. for ImmutableShortBigList.
      Parameters:
      copy - true to copy all instance values from source, if false nothing is done
      that - list to copy

    • ShortBigList

      public ShortBigList()
      Default constructor. The default block size is used.

    • ShortBigList

      public ShortBigList(int blockSize)
      Constructor.
      Parameters:
      blockSize - block size

    • ShortBigList

      public ShortBigList(Collection<Short> coll)
      Create new list with specified elements.
      Parameters:
      coll - collection with element

    • ShortBigList

      private ShortBigList(int blockSize, int firstShortBlockSize)
      Internal constructor.
      Parameters:
      blockSize - default block size
      firstShortBlockSize - block size of first block

  • Method Details

    • EMPTY

      public static ShortBigList EMPTY()
      Returns:
      unmodifiable empty instance

    • create

      public static ShortBigList create()

    • create

      public static ShortBigList create(Collection<Short> coll)
      Create new list with specified elements.
      Parameters:
      coll - collection with element
      type - of elements stored in the list
      Returns:
      created list

    • create

      public static ShortBigList create(short... elems)
      Create new list with specified elements.
      Parameters:
      elems - array with elements
      type - of elements stored in the list
      Returns:
      created list

    • blockSize

      public int blockSize()
      Returns block size used for this ShortBigList.
      Returns:
      block size used for this ShortBigList

    • doInit

      private void doInit(int blockSize, int firstShortBlockSize)
      Initialize ShortBigList.
      Parameters:
      blockSize - default block size
      firstShortBlockSize - block size of first block

    • crop

      public ShortBigList crop()
      Description copied from class: IShortList
      Returns a copy this list but without elements. The new list will have the same type as this list.
      Overrides:
      crop in class IShortList
      Returns:
      an empty copy of this list

    • isReadOnly

      public boolean isReadOnly()
      Description copied from class: IShortList
      Returns true if this list is either unmodifiable or immutable, false otherwise.
      Specified by:
      isReadOnly in class IShortList

    • copy

      public ShortBigList copy()
      Returns a shallow copy of this list. The new list will contain the same elements as the source list, i.e. the elements themselves are not copied. The capacity of the list will be set to the number of elements, i.e. size and capacity are equal. This returned list will be modifiable, i.e. a read-only list will be copied and be modifiable again.

      The copy is realized by a copy-on-write approach so also really large lists can efficiently be handled.

      Specified by:
      copy in class IShortList
      Returns:
      a modifiable copy of this list

    • clone

      public ShortBigList clone()
      Returns a shallow copy of this list. The new list will contain the same elements as the source list, i.e. the elements themselves are not copied. The capacity of the list will be set to the number of elements, i.e. size and capacity are equal. If the list is read-only, the same list is returned without change. Use IShortList.copy() to .

      The copy is realized by a copy-on-write approach so also really large lists can efficiently be handled.

      Overrides:
      clone in class IShortList
      Returns:
      a modifiable copy of this list

    • doAssign

      protected void doAssign(IShortList that)
      Description copied from class: IShortList
      Assign this list the content of the that list. This is done by bitwise copying so the that list should not be used afterwards.
      Specified by:
      doAssign in class IShortList
      Parameters:
      that - list to copy content from

    • doClone

      protected void doClone(IShortList that)
      Description copied from class: IShortList
      Initialize this object after the bitwise copy has been made by Object.clone().
      Specified by:
      doClone in class IShortList
      Parameters:
      that - source object

    • copy

      private ShortBigList.ShortBlockNode copy(ShortBigList.ShortBlockNode node)
      Create a copy of the specified node.
      Parameters:
      node - source node
      Returns:
      newly created copy of source

    • getDefaultElem

      public short getDefaultElem()
      Specified by:
      getDefaultElem in class IShortList

    • finalize

      protected void finalize()
      Overrides:
      finalize in class Object

    • size

      public int size()
      Specified by:
      size in interface IShortListable
      Specified by:
      size in class IShortList

    • capacity

      public int capacity()
      As ShortBigList grows and shrinks automatically, the term capacity does not really make sense. Therefore always -1 is returned.
      Specified by:
      capacity in class IShortList
      Returns:
      capacity of this list

    • doGet

      protected short doGet(int index)
      Description copied from class: IShortList
      Helper method for getting an element from the list. This is the only method which really gets an element. Override if you need to validity checks before getting.
      Specified by:
      doGet in class IShortList
      Parameters:
      index - index of element to return
      Returns:
      the element at the specified position in this list

    • doSet

      protected short doSet(int index, short elem)
      Description copied from class: IShortList
      Helper method for setting an element in the list. This is the only method which really sets an element. Override if you need to validity checks before setting.
      Specified by:
      doSet in class IShortList
      Parameters:
      index - index where element will be placed
      elem - element to set
      Returns:
      old element which was at the position

    • doReSet

      protected short doReSet(int index, short elem)
      Description copied from class: IShortList
      Sets an element at specified position. This method is used internally if existing elements will be moved etc. Override if you need to validity checks.
      Specified by:
      doReSet in class IShortList
      Parameters:
      index - index where element will be placed
      elem - element to set
      Returns:
      old element which was at the position

    • releaseShortBlock

      private void releaseShortBlock()
      Release current block and apply modification if pending.

    • getShortBlockIndex

      private int getShortBlockIndex(int index, boolean write, int modify)
      Returns index in block where the element with specified index is located. This method also sets currShortBlock to remember this last used block.
      Parameters:
      index - list index (0 invalid input: '<'= index invalid input: '<'= size())
      write - true if the block is needed for a write operation (set, add, remove)
      modify - modify instruction (N>0: N elements are added, Ninvalid input: '<'0: N elements are removed, 0 no change)
      Returns:
      relative index within block

    • getShortBlockIndex2

      private int getShortBlockIndex2(int index, boolean write, int modify)

    • isOnlyRootShortBlock

      private boolean isOnlyRootShortBlock()
      Returns:
      true if there is only the root block, false otherwise

    • doGetShortBlock

      private void doGetShortBlock(int index, int modify)
      Determine node/block for the specified index. The fields currNode, currShortBlockStart, and currShortBlockEnd are set. During the traversing the tree node, the nodes relative positions are changed according to the modify instruction.
      Parameters:
      index - list index for which block must be determined
      modify - modify instruction (N>0: N elements are added, Ninvalid input: '<'0: N elements are removed, 0 no change)

    • doGetShortBlockLeft

      private boolean doGetShortBlockLeft(int modify, ShortBigList.ShortBlockNode nextNode, boolean wasLeft)

    • doGetShortBlockRight

      private boolean doGetShortBlockRight(int modify, ShortBigList.ShortBlockNode nextNode, boolean wasLeft)

    • addShortBlock

      private void addShortBlock(int index, ShortBigList.ShortBlock obj)
      Adds a new element to the list.
      Parameters:
      index - the index to add before
      obj - the element to add

    • doAdd

      protected boolean doAdd(int index, short element)
      Description copied from class: IShortList
      Helper method for adding an element to the list. This is the only method which really adds an element. Override if you need to validity checks before adding.
      Specified by:
      doAdd in class IShortList
      Parameters:
      index - index where element should be added (-1 means it is up to the implementation to choose the index)
      element - element to add
      Returns:
      true if element has been added, false otherwise

    • doAddSplitShortBlock

      private void doAddSplitShortBlock(int index, short element, int pos, ShortBigList.ShortBlock newShortBlock)

    • modify

      private void modify(ShortBigList.ShortBlockNode node, int modify)
      Modify relativePosition of all nodes starting from the specified node.
      Parameters:
      node - node whose position value must be changed
      modify - modify value (>0 for add, invalid input: '<'0 for delete)

    • modifyLeftNode

      private void modifyLeftNode(ShortBigList.ShortBlockNode node, int modify)

    • modifyRightNode

      private void modifyRightNode(ShortBigList.ShortBlockNode node, int modify)

    • doRemove

      private ShortBigList.ShortBlockNode doRemove(ShortBigList.ShortBlockNode node)

    • doAddAll

      protected boolean doAddAll(int index, IShortListable list)
      Description copied from class: IShortList
      Helper method for adding multiple elements to the list. This default implementation calls doAdd() for adding each element.
      Overrides:
      doAddAll in class IShortList
      Parameters:
      index - index where element should be added (-1 is valid for adding at the end)
      list - list with elements to add
      Returns:
      true if elements have been added, false otherwise

    • doAddAllTail

      private void doAddAllTail(IShortListable list, int addPos, int addLen, int space)

    • doAddAllHead

      private void doAddAllHead(IShortListable list, int addPos, int addLen, int space)

    • doAddAllMiddle

      private void doAddAllMiddle(IShortListable list, int addPos)

    • doClear

      protected void doClear()
      Overrides:
      doClear in class IShortList

    • doRemoveAll

      protected void doRemoveAll(int index, int len)
      Description copied from class: IShortList
      Remove specified range of elements from list.
      Overrides:
      doRemoveAll in class IShortList
      Parameters:
      index - index of first element to remove
      len - number of elements to remove

    • doRemoveAll2

      private void doRemoveAll2(int index, int len, int startPos, ShortBigList.ShortBlockNode startNode, ShortBigList.ShortBlockNode endNode)

    • merge

      private void merge(ShortBigList.ShortBlockNode node)
      Merge the specified node with the left or right neighbor if possible.
      Parameters:
      node - candidate node for merge

    • doRemove

      protected short doRemove(int index)
      Description copied from class: IShortList
      Helper method to remove an element. This is the only method which really removes an element. Override if you need to validity checks before removing.
      Specified by:
      doRemove in class IShortList
      Parameters:
      index - index of element to remove
      Returns:
      removed element

    • unmodifiableList

      public ShortBigList unmodifiableList()
      Specified by:
      unmodifiableList in class IShortList

    • immutableList

      public ShortBigList immutableList()
      Description copied from class: IShortList
      Returns an immutable copy of this list. The returned list is independent from the original list, i.e. changes done later are not seen. Attempts to modify the returned list, whether direct or via its iterator, result in an UnsupportedOperationException. If this list is already immutable, it is returned unchanged. See IShortList.unmodifiableList() to get unmodifiable view of a list.
      Specified by:
      immutableList in class IShortList
      Returns:
      an immutable copy of the specified list

    • doEnsureCapacity

      protected void doEnsureCapacity(int minCapacity)
      Description copied from class: IShortList
      Increases the capacity of this list instance, if necessary, to ensure that it can hold at least the number of elements specified by the minimum capacity argument.
      Specified by:
      doEnsureCapacity in class IShortList
      Parameters:
      minCapacity - the desired minimum capacity

    • trimToSize

      public void trimToSize()
      Pack as many elements in the blocks as allowed. An application can use this operation to minimize the storage of an instance.
      Specified by:
      trimToSize in class IShortList

    • doCreate

      protected IShortList doCreate(int capacity)
      Description copied from class: IShortList
      Create list with specified capacity.
      Specified by:
      doCreate in class IShortList
      Parameters:
      capacity - initial capacity (use -1 for default capacity)
      Returns:
      created list

    • sort

      public void sort(int index, int len)
      Description copied from class: IShortList
      Sort specified elements in the list using the specified comparator.
      Specified by:
      sort in class IShortList
      Parameters:
      index - index of first element to sort
      len - number of elements to sort
      See Also:

    • binarySearch

      public int binarySearch(int index, int len, short key)
      Description copied from class: IShortList
      Searches the specified range for an object using the binary search algorithm.

      Note that the method is defined to work with an arbitrary type <K>. This allows to search directly for a key field in the object without the need to construct an object containing the key: 

      
  persons.binarySearch("john", new SearchByName());

  class SearchByName implements Comparator<Object> {
 	 public int compare(Object o1, Object o2) {
 	   String s1 = (o1 instanceof String) ? (String) o1 : ((Name) o1).getName();
 	   String s2 = (o2 instanceof String) ? (String) o2 : ((Name) o2).getName();
 	   return s1.compareTo(s2);
 	 }
  }
  /
      Specified by:
      binarySearch in class IShortList
      Parameters:
      index - index of first element to search
      len - number of elements to search
      key - the value to be searched for
      Returns:
      index of the search key, if it is contained in the array; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element greater than the key, or a.length if all elements in the array are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.
      See Also:

    • writeObject

      private void writeObject(ObjectOutputStream oos) throws IOException
      Serialize a ShortBigList object.
      Parameters:
      oos - output stream for serialization
      Throws:
      IOException - if serialization fails

    • readObject

      private void readObject(ObjectInputStream ois) throws IOException, ClassNotFoundException
      Deserialize a ShortBigList object.
      Parameters:
      ois - input stream for serialization
      Throws:
      IOException - if serialization fails
      ClassNotFoundException - if serialization fails

    • checkNode

      private void checkNode(ShortBigList.ShortBlockNode node)

    • checkHeight

      private void checkHeight(ShortBigList.ShortBlockNode node)

    • check

      private void check()