Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||||
DoubleArray |
|
| 1.0;1 |
1 | /* |
|
2 | * Copyright 2003-2004 The Apache Software Foundation. |
|
3 | * |
|
4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
|
5 | * you may not use this file except in compliance with the License. |
|
6 | * You may obtain a copy of the License at |
|
7 | * |
|
8 | * http://www.apache.org/licenses/LICENSE-2.0 |
|
9 | * |
|
10 | * Unless required by applicable law or agreed to in writing, software |
|
11 | * distributed under the License is distributed on an "AS IS" BASIS, |
|
12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
|
13 | * See the License for the specific language governing permissions and |
|
14 | * limitations under the License. |
|
15 | */ |
|
16 | package org.apache.commons.math.util; |
|
17 | ||
18 | ||
19 | /** |
|
20 | * Provides a standard interface for double arrays. Allows different |
|
21 | * array implementations to support various storage mechanisms |
|
22 | * such as automatic expansion, contraction, and array "rolling". |
|
23 | * |
|
24 | * @version $Revision$ $Date: 2005-02-26 05:11:52 -0800 (Sat, 26 Feb 2005) $ |
|
25 | */ |
|
26 | public interface DoubleArray { |
|
27 | ||
28 | /** |
|
29 | * Returns the number of elements currently in the array. Please note |
|
30 | * that this may be different from the length of the internal storage array. |
|
31 | * |
|
32 | * @return number of elements |
|
33 | */ |
|
34 | int getNumElements(); |
|
35 | ||
36 | /** |
|
37 | * Returns the element at the specified index. Note that if an |
|
38 | * out of bounds index is supplied a ArrayIndexOutOfBoundsException |
|
39 | * will be thrown. |
|
40 | * |
|
41 | * @param index index to fetch a value from |
|
42 | * @return value stored at the specified index |
|
43 | * @throws ArrayIndexOutOfBoundsException if <code>index</code> is less than |
|
44 | * zero or is greater than <code>getNumElements() - 1</code>. |
|
45 | */ |
|
46 | double getElement(int index); |
|
47 | ||
48 | /** |
|
49 | * Sets the element at the specified index. If the specified index is greater than |
|
50 | * <code>getNumElements() - 1</code>, the <code>numElements</code> property |
|
51 | * is increased to <code>index +1</code> and additional storage is allocated |
|
52 | * (if necessary) for the new element and all (uninitialized) elements |
|
53 | * between the new element and the previous end of the array). |
|
54 | * |
|
55 | * @param index index to store a value in |
|
56 | * @param value value to store at the specified index |
|
57 | * @throws ArrayIndexOutOfBoundsException if <code>index</code> is less than |
|
58 | * zero. |
|
59 | */ |
|
60 | void setElement(int index, double value); |
|
61 | ||
62 | /** |
|
63 | * Adds an element to the end of this expandable array |
|
64 | * |
|
65 | * @param value to be added to end of array |
|
66 | */ |
|
67 | void addElement(double value); |
|
68 | ||
69 | /** |
|
70 | * <p> |
|
71 | * Adds an element to the end of the array and removes the first |
|
72 | * element in the array. Returns the discarded first element. |
|
73 | * The effect is similar to a push operation in a FIFO queue. |
|
74 | * </p> |
|
75 | * <p> |
|
76 | * Example: If the array contains the elements 1, 2, 3, 4 (in that order) |
|
77 | * and addElementRolling(5) is invoked, the result is an array containing |
|
78 | * the entries 2, 3, 4, 5 and the value returned is 1. |
|
79 | * </p> |
|
80 | * |
|
81 | * @param value the value to be added to the array |
|
82 | * @return the value which has been discarded or "pushed" out of the array |
|
83 | * by this rolling insert |
|
84 | */ |
|
85 | double addElementRolling(double value); |
|
86 | ||
87 | /** |
|
88 | * Returns a double[] array containing the elements of this |
|
89 | * <code>DoubleArray</code>. If the underlying implementation is |
|
90 | * array-based, this method should always return a copy, rather than a |
|
91 | * reference to the underlying array so that changes made to the returned |
|
92 | * array have no effect on the <code>DoubleArray.</code> |
|
93 | * |
|
94 | * @return all elements added to the array |
|
95 | */ |
|
96 | double[] getElements(); |
|
97 | ||
98 | /** |
|
99 | * Clear the double array |
|
100 | */ |
|
101 | void clear(); |
|
102 | ||
103 | } |