root / branches / v2_0_0_prep / libraries / libFMap_dal / src / org / gvsig / fmap / dal / spi / AbstractDataProviderIterator.java @ 33205
History | View | Annotate | Download (3.28 KB)
1 | 31022 | cordinyana | /* gvSIG. Geographic Information System of the Valencian Government
|
---|---|---|---|
2 | *
|
||
3 | * Copyright (C) 2007-2008 Infrastructures and Transports Department
|
||
4 | 31544 | cordinyana | * of the Valencian Government (CIT)
|
5 | 31022 | cordinyana | *
|
6 | * This program is free software; you can redistribute it and/or
|
||
7 | * modify it under the terms of the GNU General Public License
|
||
8 | * as published by the Free Software Foundation; either version 2
|
||
9 | * of the License, or (at your option) any later version.
|
||
10 | *
|
||
11 | * This program is distributed in the hope that it will be useful,
|
||
12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
14 | * GNU General Public License for more details.
|
||
15 | *
|
||
16 | * You should have received a copy of the GNU General Public License
|
||
17 | * along with this program; if not, write to the Free Software
|
||
18 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
|
||
19 | * MA 02110-1301, USA.
|
||
20 | *
|
||
21 | */
|
||
22 | |||
23 | /*
|
||
24 | * AUTHORS (In addition to CIT):
|
||
25 | * 2009 {} {{Task}}
|
||
26 | */
|
||
27 | package org.gvsig.fmap.dal.spi; |
||
28 | |||
29 | 33205 | cordinyana | import org.gvsig.tools.dispose.DisposableIterator; |
30 | 31022 | cordinyana | import org.gvsig.fmap.dal.feature.spi.FeatureProvider; |
31 | import org.gvsig.fmap.dal.resource.Resource; |
||
32 | import org.gvsig.fmap.dal.resource.ResourceAction; |
||
33 | 31284 | cordinyana | import org.gvsig.tools.dispose.impl.AbstractDisposable; |
34 | 31022 | cordinyana | |
35 | /**
|
||
36 | * Abstract base implementation for data iterators.
|
||
37 | *
|
||
38 | * @author 2009- <a href="cordinyana@gvsig.org">C?sar Ordi?ana</a> - gvSIG team
|
||
39 | */
|
||
40 | 31284 | cordinyana | public abstract class AbstractDataProviderIterator extends AbstractDisposable |
41 | implements DisposableIterator {
|
||
42 | 31022 | cordinyana | |
43 | private final DataStoreProvider dataStoreProvider; |
||
44 | |||
45 | private final ResourceAction nextResourceAction = new ResourceAction() { |
||
46 | public Object run() throws Exception { |
||
47 | dataStoreProvider.open(); |
||
48 | return internalNext();
|
||
49 | } |
||
50 | }; |
||
51 | |||
52 | private final ResourceAction hasNextResourceAction = new ResourceAction() { |
||
53 | public Object run() throws Exception { |
||
54 | boolean value = internalHasNext();
|
||
55 | return value ? Boolean.TRUE : Boolean.FALSE; |
||
56 | } |
||
57 | }; |
||
58 | |||
59 | /**
|
||
60 | * Creates a new iterator instance.
|
||
61 | *
|
||
62 | * @param storeProvider
|
||
63 | * to load the {@link FeatureProvider}s from
|
||
64 | */
|
||
65 | public AbstractDataProviderIterator(DataStoreProvider dataStoreProvider) {
|
||
66 | this.dataStoreProvider = dataStoreProvider;
|
||
67 | } |
||
68 | |||
69 | public final Object next() { |
||
70 | return getResource().execute(nextResourceAction);
|
||
71 | } |
||
72 | |||
73 | public final boolean hasNext() { |
||
74 | Object hasNext = getResource().execute(hasNextResourceAction);
|
||
75 | return ((Boolean) hasNext).booleanValue(); |
||
76 | } |
||
77 | |||
78 | /**
|
||
79 | * Returns the {@link Resource} from where the data is going to be loaded.
|
||
80 | *
|
||
81 | * @return the {@link Resource} from where the data is going to be loaded
|
||
82 | */
|
||
83 | protected final Resource getResource() { |
||
84 | return getDataStoreProvider().getResource();
|
||
85 | } |
||
86 | |||
87 | /**
|
||
88 | * Returns the {@link DataStoreProvider} to load the Iterator data.
|
||
89 | *
|
||
90 | * @return the {@link DataStoreProvider}
|
||
91 | */
|
||
92 | protected DataStoreProvider getDataStoreProvider() {
|
||
93 | return dataStoreProvider;
|
||
94 | } |
||
95 | |||
96 | /**
|
||
97 | * Returns the next iterator element. It is the child classes implementation
|
||
98 | * for the {@link #next()} method.
|
||
99 | *
|
||
100 | * @return the next element
|
||
101 | */
|
||
102 | protected abstract Object internalNext(); |
||
103 | |||
104 | /**
|
||
105 | * Returns if there are more elements to get from the iterator. It is the
|
||
106 | * child classes implementation for the {@link #hasNext()} method.
|
||
107 | *
|
||
108 | * @return if there are more elements
|
||
109 | */
|
||
110 | protected abstract boolean internalHasNext(); |
||
111 | } |