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1   /*
2    * Copyright (c) 2007, James Leigh All rights reserved.
3    * 
4    * Redistribution and use in source and binary forms, with or without
5    * modification, are permitted provided that the following conditions are met:
6    * 
7    * - Redistributions of source code must retain the above copyright notice, this
8    *   list of conditions and the following disclaimer.
9    * - Redistributions in binary form must reproduce the above copyright notice,
10   *   this list of conditions and the following disclaimer in the documentation
11   *   and/or other materials provided with the distribution. 
12   * - Neither the name of the openrdf.org nor the names of its contributors may
13   *   be used to endorse or promote products derived from this software without
14   *   specific prior written permission.
15   * 
16   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19   * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
20   * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21   * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22   * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23   * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24   * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26   * POSSIBILITY OF SUCH DAMAGE.
27   * 
28   */
29  package org.openrdf.elmo.sesame.converters.impl;
30  
31  import java.lang.reflect.Method;
32  import java.lang.reflect.Modifier;
33  
34  import org.openrdf.elmo.exceptions.ElmoConversionException;
35  import org.openrdf.elmo.sesame.converters.Marshall;
36  import org.openrdf.model.Literal;
37  import org.openrdf.model.URI;
38  import org.openrdf.model.ValueFactory;
39  
40  public class ValueOfMarshall<T> implements Marshall<T> {
41  
42  	private ValueFactory vf;
43  
44  	private Method valueOfMethod;
45  
46  	private URI datatype;
47  
48  	public ValueOfMarshall(ValueFactory vf, Class<T> type)
49  			throws NoSuchMethodException {
50  		this.vf = vf;
51  		this.datatype = vf.createURI("java:", type.getName());
52  		try {
53  		this.valueOfMethod = type.getDeclaredMethod("valueOf", new Class[] { String.class });
54  		if (!Modifier.isStatic(valueOfMethod.getModifiers()))
55  			throw new NoSuchMethodException("valueOf Method is not static");
56  		if (!type.equals(valueOfMethod.getReturnType()))
57  			throw new NoSuchMethodException("Invalid return type");
58  		} catch (NoSuchMethodException e) {
59  			try {
60  				this.valueOfMethod = type.getDeclaredMethod("getInstance", new Class[] { String.class });
61  				if (!Modifier.isStatic(valueOfMethod.getModifiers()))
62  					throw new NoSuchMethodException("getInstance Method is not static");
63  				if (!type.equals(valueOfMethod.getReturnType()))
64  					throw new NoSuchMethodException("Invalid return type");
65  			} catch (NoSuchMethodException e2) {
66  				throw e;
67  			}
68  		}
69  	}
70  
71  	@SuppressWarnings("unchecked")
72  	public Class<? extends T> getJavaClass() {
73  		return (Class<? extends T>) valueOfMethod.getDeclaringClass();
74  	}
75  
76  	public URI getDatatype() {
77  		return datatype;
78  	}
79  
80  	public void setDatatype(URI datatype) {
81  		this.datatype = datatype;
82  	}
83  
84  	@SuppressWarnings("unchecked")
85  	public T deserialize(Literal literal) {
86  		try {
87  			return (T) valueOfMethod.invoke(null, new Object[] { literal.getLabel() });
88  		} catch (Exception e) {
89  			throw new ElmoConversionException(e);
90  		}
91  	}
92  
93  	public Literal serialize(T object) {
94  		return vf.createLiteral(object.toString(), datatype);
95  	}
96  
97  }