Class DoubleArrayList

  • All Implemented Interfaces:
    DoubleCollection, DoubleIterable, DoubleList, DoubleStack, Stack<java.lang.Double>, java.io.Serializable, java.lang.Cloneable, java.lang.Comparable<java.util.List<? extends java.lang.Double>>, java.lang.Iterable<java.lang.Double>, java.util.Collection<java.lang.Double>, java.util.List<java.lang.Double>, java.util.RandomAccess

    public class DoubleArrayList
    extends AbstractDoubleList
    implements java.util.RandomAccess, java.lang.Cloneable, java.io.Serializable
    A type-specific array-based list; provides some additional methods that use polymorphism to avoid (un)boxing.

    This class implements a lightweight, fast, open, optimized, reuse-oriented version of array-based lists. Instances of this class represent a list with an array that is enlarged as needed when new entries are created (by doubling its current length), but is never made smaller (even on a clear()). A family of trimming methods lets you control the size of the backing array; this is particularly useful if you reuse instances of this class. Range checks are equivalent to those of java.util's classes, but they are delayed as much as possible. The backing array is exposed by the elements() method.

    This class implements the bulk methods removeElements(), addElements() and getElements() using high-performance system calls (e.g., System.arraycopy() instead of expensive loops.

    See Also:
    ArrayList, Serialized Form
    • Field Summary

      Fields 
      Modifier and Type Field Description
      static int DEFAULT_INITIAL_CAPACITY
      The initial default capacity of an array list.
    • Constructor Summary

      Constructors 
      Constructor Description
      DoubleArrayList()
      Creates a new array list with DEFAULT_INITIAL_CAPACITY capacity.
      DoubleArrayList​(double[] a)
      Creates a new array list and fills it with the elements of a given array.
      DoubleArrayList​(double[] a, int offset, int length)
      Creates a new array list and fills it with the elements of a given array.
      DoubleArrayList​(int capacity)
      Creates a new array list with given capacity.
      DoubleArrayList​(DoubleCollection c)
      Creates a new array list and fills it with a given type-specific collection.
      DoubleArrayList​(DoubleIterator i)
      Creates a new array list and fills it with the elements returned by a type-specific iterator..
      DoubleArrayList​(DoubleList l)
      Creates a new array list and fills it with a given type-specific list.
      DoubleArrayList​(java.util.Collection<? extends java.lang.Double> c)
      Creates a new array list and fills it with a given collection.
      DoubleArrayList​(java.util.Iterator<? extends java.lang.Double> i)
      Creates a new array list and fills it with the elements returned by an iterator..
    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      boolean add​(double k)
      Ensures that this collection contains the specified element (optional operation).
      void add​(int index, double k)
      Inserts the specified element at the specified position in this list (optional operation).
      boolean addAll​(int index, DoubleCollection c)
      Inserts all of the elements in the specified type-specific collection into this type-specific list at the specified position (optional operation).
      boolean addAll​(int index, DoubleList l)
      Inserts all of the elements in the specified type-specific list into this type-specific list at the specified position (optional operation).
      void addElements​(int index, double[] a, int offset, int length)
      Adds elements to this type-specific list using optimized system calls.
      void clear()
      DoubleArrayList clone()  
      int compareTo​(DoubleArrayList l)
      Compares this array list to another array list.
      double[] elements()
      Returns the backing array of this list.
      void ensureCapacity​(int capacity)
      Ensures that this array list can contain the given number of entries without resizing.
      boolean equals​(DoubleArrayList l)
      Compares this type-specific array list to another one.
      double getDouble​(int index)
      Returns the element at the specified position in this list.
      void getElements​(int from, double[] a, int offset, int length)
      Copies element of this type-specific list into the given array using optimized system calls.
      int indexOf​(double k)
      Returns the index of the first occurrence of the specified element in this list, or -1 if this list does not contain the element.
      boolean isEmpty()
      Checks whether the stack is empty.
      int lastIndexOf​(double k)
      Returns the index of the last occurrence of the specified element in this list, or -1 if this list does not contain the element.
      DoubleListIterator listIterator​(int index)
      Returns a type-specific list iterator on the list starting at a given index.
      boolean rem​(double k)
      Removes a single instance of the specified element from this collection, if it is present (optional operation).
      boolean removeAll​(DoubleCollection c)
      Remove from this collection all elements in the given type-specific collection.
      boolean removeAll​(java.util.Collection<?> c)  
      double removeDouble​(int index)
      Removes the element at the specified position in this list (optional operation).
      void removeElements​(int from, int to)
      Removes elements of this type-specific list using optimized system calls.
      double set​(int index, double k)
      Replaces the element at the specified position in this list with the specified element (optional operation).
      int size()  
      void size​(int size)
      Sets the size of this list.
      double[] toArray​(double[] a)
      Returns an array containing all of the elements in this collection; the runtime type of the returned array is that of the specified array.
      void trim()
      Trims this array list so that the capacity is equal to the size.
      void trim​(int n)
      Trims the backing array if it is too large.
      static DoubleArrayList wrap​(double[] a)
      Wraps a given array into an array list.
      static DoubleArrayList wrap​(double[] a, int length)
      Wraps a given array into an array list of given size.
      • Methods inherited from class java.util.AbstractCollection

        containsAll, retainAll, toArray, toArray
      • Methods inherited from class java.lang.Object

        getClass, notify, notifyAll, wait, wait, wait
      • Methods inherited from interface java.util.Collection

        parallelStream, stream, toArray
      • Methods inherited from interface java.util.List

        containsAll, replaceAll, retainAll, sort, spliterator, toArray, toArray
    • Field Detail

      • DEFAULT_INITIAL_CAPACITY

        public static final int DEFAULT_INITIAL_CAPACITY
        The initial default capacity of an array list.
        See Also:
        Constant Field Values
    • Constructor Detail

      • DoubleArrayList

        public DoubleArrayList​(int capacity)
        Creates a new array list with given capacity.
        Parameters:
        capacity - the initial capacity of the array list (may be 0).
      • DoubleArrayList

        public DoubleArrayList​(java.util.Collection<? extends java.lang.Double> c)
        Creates a new array list and fills it with a given collection.
        Parameters:
        c - a collection that will be used to fill the array list.
      • DoubleArrayList

        public DoubleArrayList​(DoubleCollection c)
        Creates a new array list and fills it with a given type-specific collection.
        Parameters:
        c - a type-specific collection that will be used to fill the array list.
      • DoubleArrayList

        public DoubleArrayList​(DoubleList l)
        Creates a new array list and fills it with a given type-specific list.
        Parameters:
        l - a type-specific list that will be used to fill the array list.
      • DoubleArrayList

        public DoubleArrayList​(double[] a)
        Creates a new array list and fills it with the elements of a given array.
        Parameters:
        a - an array whose elements will be used to fill the array list.
      • DoubleArrayList

        public DoubleArrayList​(double[] a,
                               int offset,
                               int length)
        Creates a new array list and fills it with the elements of a given array.
        Parameters:
        a - an array whose elements will be used to fill the array list.
        offset - the first element to use.
        length - the number of elements to use.
      • DoubleArrayList

        public DoubleArrayList​(java.util.Iterator<? extends java.lang.Double> i)
        Creates a new array list and fills it with the elements returned by an iterator..
        Parameters:
        i - an iterator whose returned elements will fill the array list.
      • DoubleArrayList

        public DoubleArrayList​(DoubleIterator i)
        Creates a new array list and fills it with the elements returned by a type-specific iterator..
        Parameters:
        i - a type-specific iterator whose returned elements will fill the array list.
    • Method Detail

      • elements

        public double[] elements()
        Returns the backing array of this list.
        Returns:
        the backing array.
      • wrap

        public static DoubleArrayList wrap​(double[] a,
                                           int length)
        Wraps a given array into an array list of given size.

        Note it is guaranteed that the type of the array returned by elements() will be the same (see the comments in the class documentation).

        Parameters:
        a - an array to wrap.
        length - the length of the resulting array list.
        Returns:
        a new array list of the given size, wrapping the given array.
      • wrap

        public static DoubleArrayList wrap​(double[] a)
        Wraps a given array into an array list.

        Note it is guaranteed that the type of the array returned by elements() will be the same (see the comments in the class documentation).

        Parameters:
        a - an array to wrap.
        Returns:
        a new array list wrapping the given array.
      • ensureCapacity

        public void ensureCapacity​(int capacity)
        Ensures that this array list can contain the given number of entries without resizing.
        Parameters:
        capacity - the new minimum capacity for this array list.
      • add

        public void add​(int index,
                        double k)
        Description copied from class: AbstractDoubleList
        Inserts the specified element at the specified position in this list (optional operation).

        This implementation always throws an UnsupportedOperationException.

        Specified by:
        add in interface DoubleList
        Overrides:
        add in class AbstractDoubleList
        See Also:
        List.add(int,Object)
      • add

        public boolean add​(double k)
        Description copied from class: AbstractDoubleList
        Ensures that this collection contains the specified element (optional operation).

        This implementation always throws an UnsupportedOperationException.

        This implementation delegates to the type-specific version of List.add(int, Object).

        Specified by:
        add in interface DoubleCollection
        Specified by:
        add in interface DoubleList
        Overrides:
        add in class AbstractDoubleList
        See Also:
        Collection.add(Object)
      • getDouble

        public double getDouble​(int index)
        Description copied from interface: DoubleList
        Returns the element at the specified position in this list.
        Specified by:
        getDouble in interface DoubleList
        See Also:
        List.get(int)
      • indexOf

        public int indexOf​(double k)
        Description copied from interface: DoubleList
        Returns the index of the first occurrence of the specified element in this list, or -1 if this list does not contain the element.
        Specified by:
        indexOf in interface DoubleList
        Overrides:
        indexOf in class AbstractDoubleList
        See Also:
        List.indexOf(Object)
      • lastIndexOf

        public int lastIndexOf​(double k)
        Description copied from interface: DoubleList
        Returns the index of the last occurrence of the specified element in this list, or -1 if this list does not contain the element.
        Specified by:
        lastIndexOf in interface DoubleList
        Overrides:
        lastIndexOf in class AbstractDoubleList
        See Also:
        List.lastIndexOf(Object)
      • removeDouble

        public double removeDouble​(int index)
        Description copied from class: AbstractDoubleList
        Removes the element at the specified position in this list (optional operation).

        This implementation always throws an UnsupportedOperationException.

        Specified by:
        removeDouble in interface DoubleList
        Overrides:
        removeDouble in class AbstractDoubleList
        See Also:
        List.remove(int)
      • rem

        public boolean rem​(double k)
        Description copied from class: AbstractDoubleList
        Removes a single instance of the specified element from this collection, if it is present (optional operation).

        This implementation delegates to indexOf().

        Specified by:
        rem in interface DoubleCollection
        Overrides:
        rem in class AbstractDoubleList
        See Also:
        List.remove(Object)
      • set

        public double set​(int index,
                          double k)
        Description copied from class: AbstractDoubleList
        Replaces the element at the specified position in this list with the specified element (optional operation).

        This implementation always throws an UnsupportedOperationException.

        Specified by:
        set in interface DoubleList
        Overrides:
        set in class AbstractDoubleList
        See Also:
        List.set(int,Object)
      • size

        public int size()
        Specified by:
        size in interface java.util.Collection<java.lang.Double>
        Specified by:
        size in interface java.util.List<java.lang.Double>
        Specified by:
        size in class java.util.AbstractCollection<java.lang.Double>
      • size

        public void size​(int size)
        Description copied from interface: DoubleList
        Sets the size of this list.

        If the specified size is smaller than the current size, the last elements are discarded. Otherwise, they are filled with 0/null/false.

        Specified by:
        size in interface DoubleList
        Overrides:
        size in class AbstractDoubleList
        Parameters:
        size - the new size.
      • isEmpty

        public boolean isEmpty()
        Description copied from interface: Stack
        Checks whether the stack is empty.
        Specified by:
        isEmpty in interface java.util.Collection<java.lang.Double>
        Specified by:
        isEmpty in interface java.util.List<java.lang.Double>
        Specified by:
        isEmpty in interface Stack<java.lang.Double>
        Overrides:
        isEmpty in class java.util.AbstractCollection<java.lang.Double>
        Returns:
        true if the stack is empty.
      • trim

        public void trim()
        Trims this array list so that the capacity is equal to the size.
        See Also:
        ArrayList.trimToSize()
      • trim

        public void trim​(int n)
        Trims the backing array if it is too large. If the current array length is smaller than or equal to n, this method does nothing. Otherwise, it trims the array length to the maximum between n and size().

        This method is useful when reusing lists. Clearing a list leaves the array length untouched. If you are reusing a list many times, you can call this method with a typical size to avoid keeping around a very large array just because of a few large transient lists.

        Parameters:
        n - the threshold for the trimming.
      • getElements

        public void getElements​(int from,
                                double[] a,
                                int offset,
                                int length)
        Copies element of this type-specific list into the given array using optimized system calls.
        Specified by:
        getElements in interface DoubleList
        Overrides:
        getElements in class AbstractDoubleList
        Parameters:
        from - the start index (inclusive).
        a - the destination array.
        offset - the offset into the destination array where to store the first element copied.
        length - the number of elements to be copied.
      • removeElements

        public void removeElements​(int from,
                                   int to)
        Removes elements of this type-specific list using optimized system calls.
        Specified by:
        removeElements in interface DoubleList
        Overrides:
        removeElements in class AbstractDoubleList
        Parameters:
        from - the start index (inclusive).
        to - the end index (exclusive).
      • addElements

        public void addElements​(int index,
                                double[] a,
                                int offset,
                                int length)
        Adds elements to this type-specific list using optimized system calls.
        Specified by:
        addElements in interface DoubleList
        Overrides:
        addElements in class AbstractDoubleList
        Parameters:
        index - the index at which to add elements.
        a - the array containing the elements.
        offset - the offset of the first element to add.
        length - the number of elements to add.
      • toArray

        public double[] toArray​(double[] a)
        Description copied from interface: DoubleCollection
        Returns an array containing all of the elements in this collection; the runtime type of the returned array is that of the specified array.

        Note that, contrarily to Collection.toArray(Object[]), this methods just writes all elements of this collection: no special value will be added after the last one.

        Specified by:
        toArray in interface DoubleCollection
        Overrides:
        toArray in class AbstractDoubleCollection
        Parameters:
        a - if this array is big enough, it will be used to store this collection.
        Returns:
        a primitive type array containing the items of this collection.
        See Also:
        Collection.toArray(Object[])
      • addAll

        public boolean addAll​(int index,
                              DoubleCollection c)
        Description copied from interface: DoubleList
        Inserts all of the elements in the specified type-specific collection into this type-specific list at the specified position (optional operation).
        Specified by:
        addAll in interface DoubleList
        Overrides:
        addAll in class AbstractDoubleList
        See Also:
        List.addAll(int,java.util.Collection)
      • addAll

        public boolean addAll​(int index,
                              DoubleList l)
        Description copied from class: AbstractDoubleList
        Inserts all of the elements in the specified type-specific list into this type-specific list at the specified position (optional operation).

        This implementation delegates to the type-specific version of List.addAll(int, Collection).

        Specified by:
        addAll in interface DoubleList
        Overrides:
        addAll in class AbstractDoubleList
        See Also:
        List.add(int,Object)
      • removeAll

        public boolean removeAll​(DoubleCollection c)
        Description copied from interface: DoubleCollection
        Remove from this collection all elements in the given type-specific collection.
        Specified by:
        removeAll in interface DoubleCollection
        Overrides:
        removeAll in class AbstractDoubleCollection
        Parameters:
        c - a type-specific collection.
        Returns:
        true if this collection changed as a result of the call.
        See Also:
        Collection.removeAll(Collection)
      • removeAll

        public boolean removeAll​(java.util.Collection<?> c)
        Specified by:
        removeAll in interface java.util.Collection<java.lang.Double>
        Specified by:
        removeAll in interface java.util.List<java.lang.Double>
        Overrides:
        removeAll in class java.util.AbstractCollection<java.lang.Double>
      • listIterator

        public DoubleListIterator listIterator​(int index)
        Description copied from class: AbstractDoubleList
        Returns a type-specific list iterator on the list starting at a given index.

        This implementation is based on the random-access methods.

        Specified by:
        listIterator in interface DoubleList
        Specified by:
        listIterator in interface java.util.List<java.lang.Double>
        Overrides:
        listIterator in class AbstractDoubleList
        See Also:
        List.listIterator(int)
      • equals

        public boolean equals​(DoubleArrayList l)
        Compares this type-specific array list to another one.

        This method exists only for sake of efficiency. The implementation inherited from the abstract implementation would already work.

        Parameters:
        l - a type-specific array list.
        Returns:
        true if the argument contains the same elements of this type-specific array list.
      • compareTo

        public int compareTo​(DoubleArrayList l)
        Compares this array list to another array list.

        This method exists only for sake of efficiency. The implementation inherited from the abstract implementation would already work.

        Parameters:
        l - an array list.
        Returns:
        a negative integer, zero, or a positive integer as this list is lexicographically less than, equal to, or greater than the argument.