1 /*
2 * Copyright 2007-2013 smartics, Kronseder & Reiner GmbH
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16 package de.smartics.exceptions.ognl;
17
18 import ognl.Ognl;
19 import ognl.OgnlContext;
20 import ognl.OgnlException;
21
22 /**
23 * Wrapper for an OGNL expression.
24 */
25 public final class OgnlExpression
26 {
27 // ********************************* Fields *********************************
28
29 // --- constants ------------------------------------------------------------
30
31 // --- members --------------------------------------------------------------
32
33 /**
34 * The reference to the parsed expression instance.
35 */
36 private final Object expression;
37
38 // ****************************** Initializer *******************************
39
40 // ****************************** Constructors ******************************
41
42 /**
43 * Default constructor.
44 *
45 * @param expressionString the OGNL expression to parse.
46 * @throws OgnlException on any parsing problem.
47 */
48 public OgnlExpression(final String expressionString) throws OgnlException
49 {
50 expression = Ognl.parseExpression(expressionString);
51 }
52
53 // ****************************** Inner Classes *****************************
54
55 // ********************************* Methods ********************************
56
57 // --- init -----------------------------------------------------------------
58
59 // --- get&set --------------------------------------------------------------
60
61 /**
62 * Returns the reference to the parsed expression instance.
63 *
64 * @return the reference to the parsed expression instance.
65 */
66 public Object getExpression()
67 {
68 return expression;
69 }
70
71 // --- business -------------------------------------------------------------
72
73 /**
74 * Returns the value for the given context on the given root object.
75 *
76 * @param context the context of the evaluation.
77 * @param rootObject the root object to run the evaluation of the OGNL
78 * expression.
79 * @return the value of the root object referenced by the OGNL expression.
80 * @throws OgnlException on any problem encountered fetching the value.
81 */
82 public Object getValue(final OgnlContext context, final Object rootObject)
83 throws OgnlException
84 {
85 return Ognl.getValue(getExpression(), context, rootObject);
86 }
87
88 /**
89 * Sets the value dependent on the OGNL expression.
90 *
91 * @param context the context of the evaluation.
92 * @param rootObject the root object to run the evaluation of the OGNL
93 * expression.
94 * @param value the value to set.
95 * @throws OgnlException on any problem encountered setting the value.
96 */
97 public void setValue(final OgnlContext context, final Object rootObject,
98 final Object value) throws OgnlException
99 {
100 Ognl.setValue(getExpression(), context, rootObject, value);
101 }
102
103 // --- object basics --------------------------------------------------------
104
105 }