01: /*
02: * (c) Copyright 2007 by Volker Bergmann. All rights reserved.
03: *
04: * Redistribution and use in source and binary forms, with or without
05: * modification, is permitted under the terms of the
06: * GNU General Public License.
07: *
08: * For redistributing this software or a derivative work under a license other
09: * than the GPL-compatible Free Software License as defined by the Free
10: * Software Foundation or approved by OSI, you must first obtain a commercial
11: * license to this software product from Volker Bergmann.
12: *
13: * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
14: * WITHOUT A WARRANTY OF ANY KIND. ALL EXPRESS OR IMPLIED CONDITIONS,
15: * REPRESENTATIONS AND WARRANTIES, INCLUDING ANY IMPLIED WARRANTY OF
16: * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE
17: * HEREBY EXCLUDED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
18: * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
19: * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
20: * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
21: * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
22: * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
23: * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
24: * POSSIBILITY OF SUCH DAMAGE.
25: */
26:
27: package org.databene.benerator.wrapper;
28:
29: import org.databene.benerator.GeneratorProxy;
30: import org.databene.benerator.Generator;
31: import org.databene.benerator.IllegalGeneratorStateException;
32:
33: /**
34: * Generator proxy that 'loops' through a source Generator,
35: * calling reset() each time the source becomes unavailable.
36: * It becomes unavailable only if the source generator is
37: * unavailable after a reset.<br/>
38: * <br/>
39: * Created: 18.08.2007 16:55:21
40: */
41: public class CyclicGeneratorProxy<E> extends GeneratorProxy<E> {
42:
43: public CyclicGeneratorProxy(Generator<E> source) {
44: super (source);
45: }
46:
47: public boolean available() {
48: if (source == null)
49: return false;
50: if (!source.available())
51: reset();
52: return source.available(); // return false only if the source is not available after reset()
53: }
54:
55: public E generate() {
56: if (source == null)
57: throw new IllegalGeneratorStateException(
58: "Generator is not available: " + source);
59: if (!source.available())
60: reset();
61: return source.generate();
62: }
63:
64: public void close() {
65: super.close();
66: source = null;
67: }
68: }
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