%line | %branch | |||||||||
---|---|---|---|---|---|---|---|---|---|---|
org.apache.commons.jexl.util.introspection.IntrospectorBase |
|
|
1 | /* |
|
2 | * Copyright 2001,2004 The Apache Software Foundation. |
|
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 | ||
17 | package org.apache.commons.jexl.util.introspection; |
|
18 | ||
19 | ||
20 | import java.util.Map; |
|
21 | import java.util.Set; |
|
22 | import java.util.HashMap; |
|
23 | import java.util.HashSet; |
|
24 | ||
25 | import java.lang.reflect.Method; |
|
26 | ||
27 | /** |
|
28 | * This basic function of this class is to return a Method |
|
29 | * object for a particular class given the name of a method |
|
30 | * and the parameters to the method in the form of an Object[] |
|
31 | * |
|
32 | * The first time the Introspector sees a |
|
33 | * class it creates a class method map for the |
|
34 | * class in question. Basically the class method map |
|
35 | * is a Hastable where Method objects are keyed by a |
|
36 | * concatenation of the method name and the names of |
|
37 | * classes that make up the parameters. |
|
38 | * |
|
39 | * For example, a method with the following signature: |
|
40 | * |
|
41 | * public void method(String a, StringBuffer b) |
|
42 | * |
|
43 | * would be mapped by the key: |
|
44 | * |
|
45 | * "method" + "java.lang.String" + "java.lang.StringBuffer" |
|
46 | * |
|
47 | * This mapping is performed for all the methods in a class |
|
48 | * and stored for |
|
49 | * @author <a href="mailto:jvanzyl@apache.org">Jason van Zyl</a> |
|
50 | * @author <a href="mailto:bob@werken.com">Bob McWhirter</a> |
|
51 | * @author <a href="mailto:szegedia@freemail.hu">Attila Szegedi</a> |
|
52 | * @author <a href="mailto:paulo.gaspar@krankikom.de">Paulo Gaspar</a> |
|
53 | * @version $Id: IntrospectorBase.java,v 1.3 2004/02/28 13:45:21 yoavs Exp $ |
|
54 | */ |
|
55 | 52 | public class IntrospectorBase |
56 | { |
|
57 | /** |
|
58 | * Holds the method maps for the classes we know about, keyed by |
|
59 | * Class object. |
|
60 | */ |
|
61 | 30 | protected Map classMethodMaps = new HashMap(); |
62 | ||
63 | /** |
|
64 | * Holds the qualified class names for the classes |
|
65 | * we hold in the classMethodMaps hash |
|
66 | */ |
|
67 | 30 | protected Set cachedClassNames = new HashSet(); |
68 | ||
69 | /** |
|
70 | * Gets the method defined by <code>name</code> and |
|
71 | * <code>params</code> for the Class <code>c</code>. |
|
72 | * |
|
73 | * @param c Class in which the method search is taking place |
|
74 | * @param name Name of the method being searched for |
|
75 | * @param params An array of Objects (not Classes) that describe the |
|
76 | * the parameters |
|
77 | * |
|
78 | * @return The desired Method object. |
|
79 | */ |
|
80 | public Method getMethod(Class c, String name, Object[] params) |
|
81 | throws Exception |
|
82 | { |
|
83 | 1131 | if (c == null) |
84 | { |
|
85 | 0 | throw new Exception ( |
86 | "Introspector.getMethod(): Class method key was null: " + name ); |
|
87 | } |
|
88 | ||
89 | 1131 | ClassMap classMap = null; |
90 | ||
91 | 1207 | synchronized(classMethodMaps) |
92 | { |
|
93 | 1131 | classMap = (ClassMap)classMethodMaps.get(c); |
94 | ||
95 | /* |
|
96 | * if we don't have this, check to see if we have it |
|
97 | * by name. if so, then we have a classloader change |
|
98 | * so dump our caches. |
|
99 | */ |
|
100 | ||
101 | 1131 | if (classMap == null) |
102 | { |
|
103 | 90 | if ( cachedClassNames.contains( c.getName() )) |
104 | { |
|
105 | /* |
|
106 | * we have a map for a class with same name, but not |
|
107 | * this class we are looking at. This implies a |
|
108 | * classloader change, so dump |
|
109 | */ |
|
110 | 0 | clearCache(); |
111 | } |
|
112 | ||
113 | 90 | classMap = createClassMap(c); |
114 | } |
|
115 | 1055 | } |
116 | ||
117 | 1131 | return classMap.findMethod(name, params); |
118 | } |
|
119 | ||
120 | /** |
|
121 | * Creates a class map for specific class and registers it in the |
|
122 | * cache. Also adds the qualified name to the name->class map |
|
123 | * for later Classloader change detection. |
|
124 | */ |
|
125 | protected ClassMap createClassMap(Class c) |
|
126 | { |
|
127 | 90 | ClassMap classMap = new ClassMap( c ); |
128 | 90 | classMethodMaps.put(c, classMap); |
129 | 90 | cachedClassNames.add( c.getName() ); |
130 | ||
131 | 90 | return classMap; |
132 | } |
|
133 | ||
134 | /** |
|
135 | * Clears the classmap and classname |
|
136 | * caches |
|
137 | */ |
|
138 | protected void clearCache() |
|
139 | { |
|
140 | /* |
|
141 | * since we are synchronizing on this |
|
142 | * object, we have to clear it rather than |
|
143 | * just dump it. |
|
144 | */ |
|
145 | 0 | classMethodMaps.clear(); |
146 | ||
147 | /* |
|
148 | * for speed, we can just make a new one |
|
149 | * and let the old one be GC'd |
|
150 | */ |
|
151 | 0 | cachedClassNames = new HashSet(); |
152 | 0 | } |
153 | } |
This report is generated by jcoverage, Maven and Maven JCoverage Plugin. |