AbstractArray (Jython API documentation)
Date: 2022-09-10

org.python.core

## Class AbstractArray

- java.lang.Object
- - org.python.core.AbstractArray

- All Implemented Interfaces:
    java.io.Serializable

      public abstract class AbstractArray
      extends java.lang.Object
      implements java.io.Serializable

  Abstract class that manages bulk structural and data operations on arrays, defering type-specific element-wise operations to the subclass. Subclasses supply the underlying array and the type-specific operations--greatly reducing the need for casting (thus achieving array-like performances with collection-like flexibility). Also includes functionality to support integration with the the jdk's collections (via methods that return a modification increment).

  Subclasses will want to provide the following methods (which are not declared in this class since subclasses should specify the explicit return type):

  - `<type> get(int)`
  - `void set(int, <type>)`
  - `void add(<type>)`
  - `void add(int, <type>)`
  - `<type>[] toArray()`

  Clone cannot be supported since the array is not held locally. But the @link #AbstractArray(AbstractArray) constructor can be used for suclasses that need to support clone.

  This "type-specific collections" approach was originally developed by Dennis Sosnoski, who provides a more complete library at the referenced URL. Sosnoski's library does not integrate with the jdk collection classes but provides collection-like classes.

  Author:
    Clark Updike
  See Also:
    Sosnoski's Type-Specific Collection Library, Serialized Form

- - ### Constructor Summary

    Constructors
    Constructor and Description
    `AbstractArray(AbstractArray toCopy)` Since AbstractArray can support a clone method, this facilitates subclasses that want to implement clone (poor man's cloning).
    `AbstractArray(java.lang.Class type)` Creates the managed array with a default size of 10.
    `AbstractArray(java.lang.Class type, int size)` Creates the managed array with the specified size.
    `AbstractArray(java.lang.Class type, int[] dimensions)` Construtor for multi-dimensional array types.
    `AbstractArray(int size)` Use when the subclass has a preexisting array.

  - ### Method Summary

    All Methods Instance Methods Concrete Methods
    Modifier and Type | Method and Description
    --- | ---
    `void` | `appendArray(java.lang.Object ofArrayType)` Appends the supplied array, which must be an array of the same type as `this`, to the end of `this`.
    `void` | `clear()` Set the array to the empty state, clearing all the data out and nulling objects (or "zero-ing" primitives).
    `java.lang.Object` | `copyArray()` Constructs and returns a simple array containing the same data as held in this growable array.
    `int` | `getModCountIncr()` Returns the modification count increment, which is used by `AbstractList` subclasses to adjust `modCount` `AbstractList` uses it's `modCount` field to invalidate concurrent operations (like iteration) that should fail if the underlying array changes structurally during the operation.
    `int` | `getSize()` Get the number of values currently present in the array.
    `void` | `remove(int index)` Remove a value from the array.
    `void` | `remove(int start, int stop)` Removes a range from the array at the specified indices.
    `void` | `replaceSubArray(int thisStart, int thisStop, java.lang.Object srcArray, int srcStart, int srcStop)` Replace a range of this array with another subarray.
    `void` | `replaceSubArray(java.lang.Object array, int atIndex)` Allows an array type to overwrite a segment of the array.
    `void` | `setSize(int count)` Sets the number of values currently present in the array.
    `java.lang.String` | `toString()` Provides a default comma-delimited representation of array.

    - ### Methods inherited from class java.lang.Object

      `equals, getClass, hashCode, notify, notifyAll, wait, wait, wait`

- - ### Constructor Detail

    - #### AbstractArray

          public AbstractArray(AbstractArray toCopy)

      Since AbstractArray can support a clone method, this facilitates subclasses that want to implement clone (poor man's cloning). Subclasses can then do this:

           public MyManagedArray(MyManagedArray toCopy) {
               super(this);
               this.baseArray = (<my array type>) toCopy.copyArray();
               this.someProp = toCopy.someProp;
               <etc>
           }

           public Object clone() {
               return new MyManagedArray(this);
           }

      Parameters:
        `toCopy` -

    - #### AbstractArray

          public AbstractArray(int size)

      Use when the subclass has a preexisting array.
      Parameters:
        `size` - the initial size of the array

    - #### AbstractArray

          public AbstractArray(java.lang.Class type)

      Creates the managed array with a default size of 10.
      Parameters:
        `type` - array element type (primitive type or object class)

    - #### AbstractArray

          public AbstractArray(java.lang.Class type,
                               int[] dimensions)

      Construtor for multi-dimensional array types. For example, `char[][]`. This class only manages the top level dimension of the array. For single dimension arrays (the more typical usage), use the other constructors.

      Parameters:
        `type` - Array element type (primitive type or object class).
        `dimensions` - An int array specifying the dimensions. For a 2D array, something like `new int[] {10,0}` to create 10 elements each of which can hold an reference to an array of the same type.
      See Also:
        `Array.newInstance(java.lang.Class, int[])`

    - #### AbstractArray

          public AbstractArray(java.lang.Class type,
                               int size)

      Creates the managed array with the specified size.
      Parameters:
        `type` - array element type (primitive type or object class)
        `size` - number of elements initially allowed in array

  - ### Method Detail

    - #### appendArray

          public void appendArray(java.lang.Object ofArrayType)

      Appends the supplied array, which must be an array of the same type as `this`, to the end of `this`.

      `AbstractList` subclasses should update their `modCount` after calling this method.

      Parameters:
        `ofArrayType` - the array to append

    - #### clear

          public void clear()

      Set the array to the empty state, clearing all the data out and nulling objects (or "zero-ing" primitives).

      Note: This method does not set `modCountIncr` to `1` even though `java.util.ArrayList` would.

      `AbstractList` subclasses should update their `modCount` after calling this method.

    - #### copyArray

          public java.lang.Object copyArray()

      Constructs and returns a simple array containing the same data as held in this growable array.
      Returns:
        array containing a shallow copy of the data.

    - #### remove

          public void remove(int index)

      Remove a value from the array. All values above the index removed are moved down one index position.

      `AbstractList` subclasses should always increment their `modCount` method after calling this, as `remove` always causes a structural modification.

      Parameters:
        `index` - index number of value to be removed

    - #### remove

          public void remove(int start,
                             int stop)

      Removes a range from the array at the specified indices.
      Parameters:
        `start` - inclusive
        `stop` - exclusive

    - #### replaceSubArray

          public void replaceSubArray(java.lang.Object array,
                                      int atIndex)

      Allows an array type to overwrite a segment of the array. Will expand the array if `(atIndex + 1) + ofArrayType`'s length is greater than the current length.

      `AbstractList` subclasses should update their `modCount` after calling this method.

      Parameters:
        `array` -
        `atIndex` -

    - #### replaceSubArray

          public void replaceSubArray(int thisStart,
                                      int thisStop,
                                      java.lang.Object srcArray,
                                      int srcStart,
                                      int srcStop)

      Replace a range of this array with another subarray.
      Parameters:
        `thisStart` - the start index (inclusive) of the subarray in this array to be replaced
        `thisStop` - the stop index (exclusive) of the subarray in this array to be replaced
        `srcArray` - the source array from which to copy
        `srcStart` - the start index (inclusive) of the replacement subarray
        `srcStop` - the stop index (exclusive) of the replacement subarray

    - #### setSize

          public void setSize(int count)

      Sets the number of values currently present in the array. If the new size is greater than the current size, the added values are initialized to the default values. If the new size is less than the current size, all values dropped from the array are discarded.

      `AbstractList` subclasses should update their `modCount` after calling this method.

      Parameters:
        `count` - number of values to be set

    - #### getSize

          public int getSize()

      Get the number of values currently present in the array.
      Returns:
        count of values present

    - #### toString

          public java.lang.String toString()

      Provides a default comma-delimited representation of array.
      Overrides:
        `toString` in class `java.lang.Object`
      See Also:
        `Object.toString()`

    - #### getModCountIncr

          public int getModCountIncr()

      Returns the modification count increment, which is used by `AbstractList` subclasses to adjust `modCount` `AbstractList` uses it's `modCount` field to invalidate concurrent operations (like iteration) that should fail if the underlying array changes structurally during the operation.
      Returns:
        the modification count increment (0 if no change, 1 if changed)

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