1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 */
19 package org.apache.myfaces.taglib.core;
20
21 import javax.el.ELContext;
22 import javax.el.ValueExpression;
23 import javax.faces.context.FacesContext;
24 import javax.faces.validator.Validator;
25 import javax.servlet.jsp.JspException;
26
27 /**
28 * This is the base Tag for all ValidatorTags which got a minimum and a maimum attribute.
29 *
30 * @author Andreas Berger (latest modification by $Author$)
31 * @version $Revision$ $Date$
32 * @since 1.2
33 */
34 public abstract class GenericMinMaxValidatorTag<T> extends ValidatorTag
35 {
36 protected ValueExpression _minimum;
37 protected ValueExpression _maximum;
38 protected T _min = null;
39 protected T _max = null;
40
41 public void setMinimum(ValueExpression minimum)
42 {
43 _minimum = minimum;
44 }
45
46 public void setMaximum(ValueExpression maximum)
47 {
48 _maximum = maximum;
49 }
50
51 @Override
52 public void release()
53 {
54 _minimum = null;
55 _maximum = null;
56 _min = null;
57 _max = null;
58 }
59
60 /**
61 * This method returns the Validator, you have to cast it to the correct type and apply the min and max values.
62 *
63 * @return
64 * @throws JspException
65 */
66 @Override
67 protected Validator createValidator() throws JspException
68 {
69 if (null == _minimum && null == _maximum)
70 {
71 throw new JspException("a minimum and / or a maximum have to be specified");
72 }
73 ELContext elContext = FacesContext.getCurrentInstance().getELContext();
74 if (null != _minimum)
75 {
76 _min = getValue(_minimum.getValue(elContext));
77 }
78 if (null != _maximum)
79 {
80 _max = getValue(_maximum.getValue(elContext));
81 }
82 if (null != _minimum && null != _maximum)
83 {
84 if (!isMinLTMax())
85 {
86 throw new JspException("maximum limit must be greater than the minimum limit");
87 }
88 }
89 return super.createValidator();
90 }
91
92 /**
93 * @return true if min is lower than max
94 */
95 protected abstract boolean isMinLTMax();
96
97 /**
98 * Wrapper method.
99 *
100 * @param value
101 * @return
102 */
103 protected abstract T getValue(Object value);
104 }