1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
|
/*
* Copyright 2011 Vaadin Ltd.
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not
* use this file except in compliance with the License. You may obtain a copy of
* the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations under
* the License.
*/
package com.vaadin.data.util.converter;
import java.io.Serializable;
import java.util.Locale;
/**
* Interface that implements conversion between a model and a presentation type.
* <p>
* Typically {@link #convertToPresentation(Object, Locale)} and
* {@link #convertToModel(Object, Locale)} should be symmetric so that chaining
* these together returns the original result for all input but this is not a
* requirement.
* </p>
* <p>
* Converters must not have any side effects (never update UI from inside a
* converter).
* </p>
* <p>
* All Converters must be stateless and thread safe.
* </p>
* <p>
* If conversion of a value fails, a {@link ConversionException} is thrown.
* </p>
*
* @param <MODEL>
* The model type. Must be compatible with what
* {@link #getModelType()} returns.
* @param <PRESENTATION>
* The presentation type. Must be compatible with what
* {@link #getPresentationType()} returns.
* @author Vaadin Ltd.
* @since 7.0
*/
public interface Converter<PRESENTATION, MODEL> extends Serializable {
/**
* Converts the given value from target type to source type.
* <p>
* A converter can optionally use locale to do the conversion.
* </p>
* A converter should in most cases be symmetric so chaining
* {@link #convertToPresentation(Object, Locale)} and
* {@link #convertToModel(Object, Locale)} should return the original value.
*
* @param value
* The value to convert, compatible with the target type. Can be
* null
* @param locale
* The locale to use for conversion. Can be null.
* @return The converted value compatible with the source type
* @throws ConversionException
* If the value could not be converted
*/
public MODEL convertToModel(PRESENTATION value, Locale locale)
throws ConversionException;
/**
* Converts the given value from source type to target type.
* <p>
* A converter can optionally use locale to do the conversion.
* </p>
* A converter should in most cases be symmetric so chaining
* {@link #convertToPresentation(Object, Locale)} and
* {@link #convertToModel(Object, Locale)} should return the original value.
*
* @param value
* The value to convert, compatible with the target type. Can be
* null
* @param locale
* The locale to use for conversion. Can be null.
* @return The converted value compatible with the source type
* @throws ConversionException
* If the value could not be converted
*/
public PRESENTATION convertToPresentation(MODEL value, Locale locale)
throws ConversionException;
/**
* The source type of the converter.
*
* Values of this type can be passed to
* {@link #convertToPresentation(Object, Locale)}.
*
* @return The source type
*/
public Class<MODEL> getModelType();
/**
* The target type of the converter.
*
* Values of this type can be passed to
* {@link #convertToModel(Object, Locale)}.
*
* @return The target type
*/
public Class<PRESENTATION> getPresentationType();
/**
* An exception that signals that the value passed to
* {@link Converter#convertToPresentation(Object, Locale)} or
* {@link Converter#convertToModel(Object, Locale)} could not be converted.
*
* @author Vaadin Ltd
* @since 7.0
*/
public static class ConversionException extends RuntimeException {
/**
* Constructs a new <code>ConversionException</code> without a detail
* message.
*/
public ConversionException() {
}
/**
* Constructs a new <code>ConversionException</code> with the specified
* detail message.
*
* @param msg
* the detail message
*/
public ConversionException(String msg) {
super(msg);
}
/**
* Constructs a new {@code ConversionException} with the specified
* cause.
*
* @param cause
* The cause of the the exception
*/
public ConversionException(Throwable cause) {
super(cause);
}
/**
* Constructs a new <code>ConversionException</code> with the specified
* detail message and cause.
*
* @param message
* the detail message
* @param cause
* The cause of the the exception
*/
public ConversionException(String message, Throwable cause) {
super(message, cause);
}
}
}
|
