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Java > Open Source Codes > org > apache > commons > collections > primitives > AbstractDoubleCollection


1 /*
2  * Licensed to the Apache Software Foundation (ASF) under one or more
3  * contributor license agreements. See the NOTICE file distributed with
4  * this work for additional information regarding copyright ownership.
5  * The ASF licenses this file to You under the Apache License, Version 2.0
6  * (the "License"); you may not use this file except in compliance with
7  * the License. You may obtain a copy of the License at
8  *
9  * http://www.apache.org/licenses/LICENSE-2.0
10  *
11  * Unless required by applicable law or agreed to in writing, software
12  * distributed under the License is distributed on an "AS IS" BASIS,
13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  * See the License for the specific language governing permissions and
15  * limitations under the License.
16  */
17 package org.apache.commons.collections.primitives;
18
19 /**
20  * Abstract base class for {@link DoubleCollection}s.
21  * <p />
22  * Read-only subclasses must override {@link #iterator}
23  * and {@link #size}. Mutable subclasses
24  * should also override {@link #add} and
25  * {@link DoubleIterator#remove DoubleIterator.remove}.
26  * All other methods have at least some base implementation
27  * derived from these. Subclasses may choose to override
28  * these methods to provide a more efficient implementation.
29  *
30  * @since Commons Primitives 1.0
31  * @version $Revision: 480460 $ $Date: 2006-11-29 00:14:21 -0800 (Wed, 29 Nov 2006) $
32  *
33  * @author Rodney Waldhoff
34  */
35 public abstract class AbstractDoubleCollection implements DoubleCollection {
36     public abstract DoubleIterator iterator();
37     public abstract int size();
38           
39     protected AbstractDoubleCollection() { }
40               
41     /** Unsupported in this base implementation. */
42     public boolean add(double element) {
43         throw new UnsupportedOperationException JavaDoc("add(double) is not supported.");
44     }
45
46     public boolean addAll(DoubleCollection c) {
47         boolean modified = false;
48         for(DoubleIterator iter = c.iterator(); iter.hasNext(); ) {
49             modified |= add(iter.next());
50         }
51         return modified;
52     }
53     
54     public void clear() {
55         for(DoubleIterator iter = iterator(); iter.hasNext();) {
56             iter.next();
57             iter.remove();
58         }
59     }
60
61     public boolean contains(double element) {
62         for(DoubleIterator iter = iterator(); iter.hasNext();) {
63             if(iter.next() == element) {
64                 return true;
65             }
66         }
67         return false;
68     }
69         
70     public boolean containsAll(DoubleCollection c) {
71         for(DoubleIterator iter = c.iterator(); iter.hasNext();) {
72             if(!contains(iter.next())) {
73                 return false;
74             }
75         }
76         return true;
77     }
78     
79     public boolean isEmpty() {
80         return (0 == size());
81     }
82        
83     public boolean removeElement(double element) {
84         for(DoubleIterator iter = iterator(); iter.hasNext();) {
85             if(iter.next() == element) {
86                 iter.remove();
87                 return true;
88             }
89         }
90         return false;
91     }
92     
93     public boolean removeAll(DoubleCollection c) {
94         boolean modified = false;
95         for(DoubleIterator iter = c.iterator(); iter.hasNext(); ) {
96             modified |= removeElement(iter.next());
97         }
98         return modified;
99     }
100     
101     public boolean retainAll(DoubleCollection c) {
102         boolean modified = false;
103         for(DoubleIterator iter = iterator(); iter.hasNext();) {
104             if(!c.contains(iter.next())) {
105                 iter.remove();
106                 modified = true;
107             }
108         }
109         return modified;
110     }
111     
112     public double[] toArray() {
113         double[] array = new double[size()];
114         int i = 0;
115         for(DoubleIterator iter = iterator(); iter.hasNext();) {
116             array[i] = iter.next();
117             i++;
118         }
119         return array;
120     }
121         
122     public double[] toArray(double[] a) {
123         if(a.length < size()) {
124             return toArray();
125         } else {
126             int i = 0;
127             for(DoubleIterator iter = iterator(); iter.hasNext();) {
128                 a[i] = iter.next();
129                 i++;
130             }
131             return a;
132         }
133     }
134 }
135
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