|
1
34
35 package com.micronova.jsp.tag;
36
37 import javax.servlet.jsp.el.*;
38 import java.lang.reflect.*;
39 import java.util.*;
40 import com.micronova.util.*;
41
42
57
58 public class CodecFunctionMapper implements FunctionMapper
59 {
60 protected static CodecFunctionMapper defaultCodecFunctionMapper;
61
62 protected static final String  STANDARDFUNCTIONS = "org.apache.taglibs.standard.functions.Functions";
63 protected static Map standardFunctionsMap;
64
65 public static final String FIND_MIN = "min";
66 public static final String FIND_MAX = "max";
67
68 static
69 {
70 defaultCodecFunctionMapper = new CodecFunctionMapper();
71
72 try
73 {
74 standardFunctionsMap = new HashMap();
75
76 Method[] methods = Class.forName(STANDARDFUNCTIONS).getMethods();
77
78 for (int i = 0; i < methods.length; i ++)
79 {
80 Method method = methods[i];
81
82 standardFunctionsMap.put(method.getName(), method);
83 }
84 }
85 catch (Exception e)
86 {
87 }
88 }
89
90 protected static Method findMethodForName(Class classObject, String name, String findType)
91 {
92 Method[] methods = classObject.getMethods();
93
94 Method methodFound = null;
95 int methodFoundParamCount = 0;
96
97 for (int i = 0; i < methods.length; i ++)
98 {
99 Method method = methods[i];
100
101 if (name.equals(method.getName()))
102 {
103 int paramCount = method.getParameterTypes().length;
104
105 boolean isMatch = (methodFound == null);
106
107 if (!isMatch)
108 {
109 if (FIND_MIN.equals(findType))
110 {
111 isMatch = (paramCount < methodFoundParamCount);
112 }
113 else if (FIND_MAX.equals(findType))
114 {
115 isMatch = (paramCount > methodFoundParamCount);
116 }
117 }
118
119 if (isMatch)
120 {
121 methodFound = method;
122 methodFoundParamCount = paramCount;
123 }
124 }
125 }
126
127 return methodFound;
128 }
129
130
131 protected CodecFunctionMapper()
132 {
133 super();
134 }
135
136 public static FunctionMapper getInstance()
137 {
138 return defaultCodecFunctionMapper;
139 }
140
141 public Method resolveFunction(String prefix, String name)
142 {
143 try
144 {
145
147 if ("fn".equals(prefix))
148 {
149 return (Method)standardFunctionsMap.get(name);
150 }
151
152 List namePartList = StringUtil.split(name, '_');
153 int namePartListSize = namePartList.size();
154
155 String codecName = prefix;
156 String codecMethod = name;
157 String argSpec = FIND_MIN;
158
159 if ("m".equals(prefix))
160 {
161 codecName = (String )namePartList.get(0);
162 codecMethod = (String )namePartList.get(1);
163
164 if (namePartListSize > 2)
165 {
166 argSpec = (String )namePartList.get(2);
167 }
168 }
169 else if (namePartListSize > 1)
170 {
171 codecMethod = (String )namePartList.get(0);
172 argSpec = (String )namePartList.get(1);
173 }
174
175 if (codecName.indexOf('.') < 0)
176 {
177 codecName = EL.CODECPATH + codecName;
178 }
179
180 Class c = Class.forName(codecName);
181
182 if (FIND_MAX.equals(argSpec) || FIND_MIN.equals(argSpec))
183 {
184 return findMethodForName(c, codecMethod, argSpec);
185 }
186 else
187 {
188 int numArgs = Integer.parseInt(argSpec);
189
190 Class [] types = new Class [numArgs];
191
192 for (int i = numArgs; --i >=0;)
193 {
194 types[i] = Object .class;
195 }
196
197 return c.getDeclaredMethod(codecMethod, types);
198 }
199 }
200 catch (Exception e)
201 {
202 throw new RuntimeException (e);
203 }
204 }
205 }
206 |
Popular Tags |
Java API By Example, From Geeks To Geeks.