java.lang.Object
org.magicwerk.brownies.collections.primitive.ILongList
org.magicwerk.brownies.collections.primitive.LongGapList
Record Components:
type - of elements stored in the list
All Implemented Interfaces:
Serializable, Cloneable, ILongListable
Direct Known Subclasses:
LongBigList.LongBlock, LongGapList.ReadOnlyList

public class LongGapList extends ILongList
Class {link LongGapList} combines the strengths of both ArrayList and LinkedList. It is implemented to offer both efficient random access to elements by index (as ArrayList does) and at the same time efficient adding and removing elements to and from beginning and end (as LinkedList does). It also exploits the locality of reference often seen in applications to further improve performance, e.g. for iterating over the list.

The class can be used as drop-in replacement for ArrayList. It is also source compatible to LinkedList/Deque as it implements all needed methods. It cannot implement Deque however, use

invalid reference
#asDeque
to get a view implementing it.

Note that this implementation is not synchronized.

Note that the iterators provided are not fail-fast.

See Also:
  • Field Details

    • DEBUG_CHECK

      private static final boolean DEBUG_CHECK
      If true the invariants the LongGapList are checked for debugging
      See Also:
    • DEBUG_TRACE

      private static final boolean DEBUG_TRACE
      If true the calls to some methods are traced out for debugging
      See Also:
    • DEBUG_DUMP

      private static final boolean DEBUG_DUMP
      If true the internal state of the LongGapList is traced out for debugging
      See Also:
    • EMPTY_VALUES

      private static long[] EMPTY_VALUES
      Empty array used for default initialization
    • EMPTY

      private static final LongGapList EMPTY
      Unmodifiable empty instance
    • serialVersionUID

      private static final long serialVersionUID
      UID for serialization
      See Also:
    • DEFAULT_CAPACITY

      public static final int DEFAULT_CAPACITY
      Default capacity for list
      See Also:
    • values

      private long[] values
      Array holding raw data
    • size

      private int size
      Number of elements stored in this LongGapList
    • start

      private int start
      Physical position of first element
    • end

      private int end
      Physical position after last element
    • gapSize

      private int gapSize
      Size of gap (0 if there is no gap)
    • gapIndex

      private int gapIndex
      Logical index of first element after gap (ignored if gapSize=0)
    • gapStart

      private int gapStart
      Physical position of first slot in gap (ignored if gapSize=0)
    • gapAddRight

      private boolean gapAddRight
      If false (default) an element is added on the left side of the gap (favorable for adding after an insertion point, e.g. indexes 5, 6, 7), if true the element is added on the right side of the gap (favorable for adding before an insertion point, e.g. indexes 5, 5, 5)
  • Constructor Details

    • LongGapList

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

      public LongGapList()
      Construct a list with the default initial capacity.
    • LongGapList

      public LongGapList(int capacity)
      Construct a list with specified initial capacity.
      Parameters:
      capacity - capacity
    • LongGapList

      public LongGapList(Collection<Long> coll)
      Construct a list to contain the specified elements. The list will have an initial capacity to hold these elements.
      Parameters:
      coll - collection with elements
  • Method Details

    • EMPTY

      public static LongGapList EMPTY()
      Returns:
      unmodifiable empty instance
    • create

      public static LongGapList create()
    • create

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

      @SafeVarargs public static LongGapList create(long... elems)
      Create new list with specified elements.
      Parameters:
      elems - array with elements
      type - of elements stored in the list
      Returns:
      created list
    • immutable

      public static LongGapList immutable(Collection<Long> coll)
      Create new immutable list with specified elements. To reduce the needed memory, the list's capacity will be equal to its size.
      Parameters:
      coll - collection with elements
      type - of elements stored in the list
      Returns:
      created list
    • immutable

      @SafeVarargs public static LongGapList immutable(long... elems)
      Create new immutable list with specified elements. To reduce the needed memory, the list's capacity will be equal to its size.
      Parameters:
      elems - array with elements
      type - of elements stored in the list
      Returns:
      created list
    • physIndex

      private final int physIndex(int idx)
      Calculate index for physical access to an element.
      Parameters:
      idx - logical index of element
      Returns:
      physical index to access element in values[]
    • physIndex

      private int[] physIndex(int idx0, int idx1)
      Calculate indexes for physical access to a range of elements. The method returns between one and three ranges of physical indexes.
      Parameters:
      idx0 - start index
      idx1 - end index
      Returns:
      array with physical start and end indexes (may contain 0, 2, 4, or 6 elements)
    • doPhysIndex

      private int[] doPhysIndex(int pidx0, int pidx1)
    • doPhysIndex2

      private int[] doPhysIndex2(int pidx0, int pidx1)
    • doAssign

      protected void doAssign(ILongList that)
      Description copied from class: ILongList
      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 ILongList
      Parameters:
      that - list to copy content from
    • init

      void init()
      Initialize the list to be empty. The list will have the default initial capacity.
    • init

      void init(Collection<Long> coll)
      Initialize the list to contain the specified elements only. The list will have an initial capacity to hold these elements.
      Parameters:
      coll - collection with elements
    • init

      void init(long... elems)
      Initialize the list to contain the specified elements only. The list will have an initial capacity to hold these elements.
      Parameters:
      elems - array with elements
    • getDefaultElem

      public long getDefaultElem()
      Specified by:
      getDefaultElem in class ILongList
    • crop

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

      public LongGapList copy()
      Description copied from class: ILongList
      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.
      Specified by:
      copy in class ILongList
      Returns:
      a modifiable copy of this list
    • clone

      public LongGapList clone()
      Description copied from class: ILongList
      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 ILongList.copy() to .
      Overrides:
      clone in class ILongList
      Returns:
      a modifiable copy of this list
    • isReadOnly

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

      public LongGapList unmodifiableList()
      Specified by:
      unmodifiableList in class ILongList
    • immutableList

      public LongGapList immutableList()
      Description copied from class: ILongList
      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 ILongList.unmodifiableList() to get unmodifiable view of a list.
      Specified by:
      immutableList in class ILongList
      Returns:
      an immutable copy of the specified list
    • doClone

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

      void ensureNormalized(int minCapacity)
      Normalize data of LongGapList so the elements are found from values[0] to values[size-1]. This method can help to speed up operations like sort or binarySearch.
    • isNormalized

      boolean isNormalized()
      Checks whether elements are stored normalized, i.e. start is at position 0 and there is no gap.
    • init

      void init(long[] values, int size)
      Initialize all instance fields.
      Parameters:
      values - new values array
      size - new size
    • doClear

      protected void doClear()
      Overrides:
      doClear in class ILongList
    • size

      public int size()
      Specified by:
      size in interface ILongListable
      Specified by:
      size in class ILongList
    • capacity

      public int capacity()
      Description copied from class: ILongList
      Returns capacity of this list. Note that two lists are considered equal even if they have a distinct capacity. Also the capacity can be changed by operations like clone() etc.
      Specified by:
      capacity in class ILongList
      Returns:
      capacity of this list
    • get

      public long get(int index)
      Specified by:
      get in interface ILongListable
      Overrides:
      get in class ILongList
    • doGet

      protected long doGet(int index)
      Description copied from class: ILongList
      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 ILongList
      Parameters:
      index - index of element to return
      Returns:
      the element at the specified position in this list
    • doSet

      protected long doSet(int index, long elem)
      Description copied from class: ILongList
      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 ILongList
      Parameters:
      index - index where element will be placed
      elem - element to set
      Returns:
      old element which was at the position
    • doReSet

      protected long doReSet(int index, long elem)
      Description copied from class: ILongList
      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 ILongList
      Parameters:
      index - index where element will be placed
      elem - element to set
      Returns:
      old element which was at the position
    • add

      public boolean add(long elem)
      Overrides:
      add in class ILongList
    • add

      public void add(int index, long elem)
      Description copied from class: ILongList
      Inserts the specified element at the specified position in this list. Shifts the element currently at that position (if any) and any subsequent elements to the right (adds one to their indices).
      Overrides:
      add in class ILongList
      Parameters:
      index - index at which the specified element is to be inserted
      elem - element to be inserted
    • getAll

      public LongGapList getAll(int index, int len)
      Description copied from class: ILongList
      Returns specified range of elements from list.
      Overrides:
      getAll in class ILongList
      Parameters:
      index - index of first element to retrieve
      len - number of elements to retrieve
      Returns:
      list containing the specified range of elements
    • getAll

      public LongGapList getAll(long elem)
      Description copied from class: ILongList
      Returns all elements in the list equal to the specified element.
      Overrides:
      getAll in class ILongList
      Parameters:
      elem - element to look for
      Returns:
      all elements in the list equal to the specified element
    • map

      public <R> GapList<R> map(Function<Long,R> mapper)
      Overrides:
      map in class ILongList
    • prepareAddBuffer

      long[] prepareAddBuffer(int index, int len)
      Prepare direct access to an array buffer for fast adding elements to the list. The size of the list will be increased by len being index+len after the call. The added elements will be initialized to their default value. If not all elements prepared are used, call releaseAddBuffer(int, int) to release them.

      Example:

       int index = list.size()
       int len = 1000;
       byte[] values = list.getAddBuffer(index, len)
       int read = inputstream.read(values, index, len)
       list.releaseAddBuffer(index, read)
       
      Parameters:
      index - index of first buffer position (must be equal to the size of the list)
      len - number of elements which the buffer can held
      Returns:
      array holding the elements of the list
    • releaseAddBuffer

      void releaseAddBuffer(int index, int len)
      Releases the buffer retrieved by prepareAddBuffer(int, int). The size of the list will be index+len after the call.
      Parameters:
      index - index of first buffer position as passed to prepareAddBuffer(int, int)
      len - number of elements used in the buffer
    • doAdd

      protected boolean doAdd(int index, long elem)
      Description copied from class: ILongList
      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 ILongList
      Parameters:
      index - index where element should be added (-1 means it is up to the implementation to choose the index)
      elem - element to add
      Returns:
      true if element has been added, false otherwise
    • doAddCreateNewGap

      private int doAddCreateNewGap(int index, int physIdx)
    • doAddCreateNewGap2

      private int doAddCreateNewGap2(int index, int physIdx)
    • doAddMoveExistingGap

      private int doAddMoveExistingGap(int index, int physIdx)
    • doAddMoveExistingGap2

      private int doAddMoveExistingGap2(int index, int physIdx, int gapEnd, boolean moveLeft)
    • moveDataWithGap

      private void moveDataWithGap(int src, int dst, int len)
      Move a range of elements in the values array and adjust the gap. The elements are first copied and the source range is then filled with null.
      Parameters:
      src - start index of source range
      dst - start index of destination range
      len - number of elements to move
    • moveData

      private void moveData(int src, int dst, int len)
      Move a range of elements in the values array. The elements are first copied and the source range is then filled with null.
      Parameters:
      src - start index of source range
      dst - start index of destination range
      len - number of elements to move
    • remove

      public long remove(int index)
      Overrides:
      remove in class ILongList
    • doRemove

      protected long doRemove(int index)
      Description copied from class: ILongList
      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 ILongList
      Parameters:
      index - index of element to remove
      Returns:
      removed element
    • doRemoveMiddle

      private void doRemoveMiddle(int index, int physIdx)
    • doRemoveMoveExistingGap

      private void doRemoveMoveExistingGap(int index, int physIdx)
    • doEnsureCapacity

      protected void doEnsureCapacity(int minCapacity)
      Description copied from class: ILongList
      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 ILongList
      Parameters:
      minCapacity - the desired minimum capacity
    • calculateNewCapacity

      int calculateNewCapacity(int minCapacity)
      Calculate new capacity. The capacity will not shrink, so the returned capacity can be equal to values.length.
      Parameters:
      minCapacity - the desired minimum capacity
      Returns:
      the new capacity to use
    • trimToSize

      public void trimToSize()
      Trims the capacity of this LongGapList instance to be the list's current size. An application can use this operation to minimize the storage of an instance.
      Specified by:
      trimToSize in class ILongList
    • doGetAll

      protected void doGetAll(long[] array, int index, int len)
      Description copied from class: ILongList
      Helper method to fill the specified elements in an array.
      Overrides:
      doGetAll in class ILongList
      Parameters:
      array - array to store the list elements
      index - index of first element to copy
      len - number of elements to copy
    • writeObject

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

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

      public LongGapList doCreate(int capacity)
      Description copied from class: ILongList
      Create list with specified capacity.
      Specified by:
      doCreate in class ILongList
      Parameters:
      capacity - initial capacity (use -1 for default capacity)
      Returns:
      created list
    • doRemoveAll

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

      protected boolean doRemoveAllFast(int index, int len)
      Remove specified range of elements from list as specialized fast operation.
      Parameters:
      index - index of first element to remove
      len - number of elements to remove
      Returns:
      true if removal could be done, false otherwise
    • sort

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

      public int binarySearch(int index, int len, long key)
      Description copied from class: ILongList
      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 ILongList
      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:
    • debugCheck

      private void debugCheck()
      Private method to check invariant of LongGapList. It is only used for debugging.
    • debugState

      private int debugState()
      Private method to determine state of LongGapList. It is only used for debugging.
      Returns:
      state in which LongGapList is
    • debugDump

      private void debugDump()
      Private method to dump fields of LongGapList. It is only called if the code is run in development mode.
    • debugPrint

      private String debugPrint(long[] values)
      Print array values into string.
      Parameters:
      values - array with values
      Returns:
      string representing array values
    • debugLog

      private void debugLog(String msg)
      Private method write logging output. It is only used for debugging.
      Parameters:
      msg - message to write out