|
|||||||||||||||||||
Source file | Conditionals | Statements | Methods | TOTAL | |||||||||||||||
EnhancementOperation.java | - | - | - | - |
|
1 | // Copyright 2004, 2005 The Apache Software Foundation | |
2 | // | |
3 | // Licensed under the Apache License, Version 2.0 (the "License"); | |
4 | // you may not use this file except in compliance with the License. | |
5 | // You may obtain a copy of the License at | |
6 | // | |
7 | // http://www.apache.org/licenses/LICENSE-2.0 | |
8 | // | |
9 | // Unless required by applicable law or agreed to in writing, software | |
10 | // distributed under the License is distributed on an "AS IS" BASIS, | |
11 | // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
12 | // See the License for the specific language governing permissions and | |
13 | // limitations under the License. | |
14 | ||
15 | package org.apache.tapestry.enhance; | |
16 | ||
17 | import java.util.List; | |
18 | ||
19 | import org.apache.hivemind.Location; | |
20 | import org.apache.hivemind.service.MethodSignature; | |
21 | ||
22 | /** | |
23 | * A process object representing enhancements to a component class. The operation is passed to | |
24 | * {@link org.apache.tapestry.enhance.EnhancementWorker}objects that perform enhancements. | |
25 | * | |
26 | * @author Howard M. Lewis Ship | |
27 | * @since 4.0 | |
28 | */ | |
29 | public interface EnhancementOperation | |
30 | { | |
31 | /** | |
32 | * Claims a property. Most enhancements are concerned with adding properties. Some enhancement | |
33 | * workers exist to fill in defaults, and they need to know what properties have already been | |
34 | * spoken for by eariler enhancement works. | |
35 | * | |
36 | * @throws org.apache.hivemind.ApplicationRuntimeException | |
37 | * if the property was previously claimed | |
38 | */ | |
39 | ||
40 | public void claimProperty(String propertyName); | |
41 | ||
42 | /** | |
43 | * Claims a property as read-only. This will check to see if the property has an abstract setter | |
44 | * method. | |
45 | * | |
46 | * @throws org.apache.hivemind.ApplicationRuntimeException | |
47 | * if the property was previously claimed, or if the property includes an accessor | |
48 | * method. | |
49 | */ | |
50 | ||
51 | public void claimReadonlyProperty(String propertyName); | |
52 | ||
53 | /** | |
54 | * Returns a list of the names of existing properties that are not claimed and which have | |
55 | * abstract accessor methods. | |
56 | */ | |
57 | ||
58 | public List findUnclaimedAbstractProperties(); | |
59 | ||
60 | /** | |
61 | * Adds a field to the enhanced class; the field will be private and use the provided name and | |
62 | * type. | |
63 | */ | |
64 | ||
65 | public void addField(String name, Class type); | |
66 | ||
67 | /** | |
68 | * Adds a field containing an initial value, which is injected into the class via its fabricated | |
69 | * constructor. This method may be called multiple times with the same value and will return the | |
70 | * same variable name (an identity map is kept internally). | |
71 | * | |
72 | * @param fieldName | |
73 | * The default name for the field, used if a new field (and contructor argument) is | |
74 | * being created. Only used if a field for the value doesn't exist. | |
75 | * @param fieldType | |
76 | * The type of the field to be created. | |
77 | * @param value | |
78 | * the value to be referenced, which may not be null | |
79 | * @return the name of the field containing the value. This may or may not match fieldName. The | |
80 | * provided fieldName may be modified to prevent naming conflicts. | |
81 | */ | |
82 | ||
83 | public String addInjectedField(String fieldName, Class fieldType, Object value); | |
84 | ||
85 | /** | |
86 | * Converts a type name (an object class name, a primtive name, or an array) into the | |
87 | * corresponding Class object. | |
88 | */ | |
89 | ||
90 | public Class convertTypeName(String type); | |
91 | ||
92 | /** | |
93 | * Confirms that the named property either doesn't exist (in the component base class), or that | |
94 | * the type of the property exactly matches the indicated type. | |
95 | */ | |
96 | ||
97 | public void validateProperty(String name, Class expectedType); | |
98 | ||
99 | /** | |
100 | * Returns the name of the accessor method for the given property (if it exists in the component | |
101 | * base class), or fabricates a new name if it does not. | |
102 | */ | |
103 | ||
104 | public String getAccessorMethodName(String propertyName); | |
105 | ||
106 | /** | |
107 | * Adds a method to the enhanced class. | |
108 | * | |
109 | * @param modifier | |
110 | * as defined by {@link java.lang.reflect.Modifier}, typically | |
111 | * {@link java.lang.reflect.Modifier#PUBLIC} | |
112 | * @param sig | |
113 | * the method signature (defining name, return type, etc.) | |
114 | * @param methodBody | |
115 | * a Javassist code snippet for the method body | |
116 | * @param location | |
117 | * a location used to identify "why" the method was added; the location may later be | |
118 | * used to describe conflicts. May not be null. | |
119 | */ | |
120 | public void addMethod(int modifier, MethodSignature sig, String methodBody, Location location); | |
121 | ||
122 | /** | |
123 | * Returns the base component class, as defined in the specification (or defaulted). An enhaced | |
124 | * subclass of the component class will usually be created. | |
125 | */ | |
126 | public Class getBaseClass(); | |
127 | ||
128 | /** | |
129 | * Returns a reference to a particular class. This will, effectively, by the name of a private | |
130 | * field. | |
131 | */ | |
132 | ||
133 | public String getClassReference(Class clazz); | |
134 | ||
135 | /** | |
136 | * Returns the type of an existing property of the base component class. If the property does | |
137 | * not exist, then returns null. | |
138 | */ | |
139 | ||
140 | public Class getPropertyType(String name); | |
141 | ||
142 | /** | |
143 | * Allows for a kind of distributed construction of a particular method, within a particular | |
144 | * interface. Code can be appended to the method's implementation throughout the course of the | |
145 | * enhancement operation. When the enhanced class is finialized, the method is added with | |
146 | * whatever contents are in its body. If the base class implements the method, then the method | |
147 | * body will include an initial call to that implementation. | |
148 | * <p> | |
149 | * At this time, this works best for void methods (since there isn't an easy way to ensure code | |
150 | * would be inserted before a final return statement). | |
151 | * | |
152 | * @param interfaceClass | |
153 | * the interface containing the method. If the base class does not implement the | |
154 | * interface, then the enhanced class will have the interface added. | |
155 | * @param methodSignature | |
156 | * the signature of the method to be added. | |
157 | * @param code | |
158 | * the Javassist markup to be added to the body of the method. | |
159 | */ | |
160 | public void extendMethodImplementation(Class interfaceClass, MethodSignature methodSignature, | |
161 | String code); | |
162 | ||
163 | /** | |
164 | * Returns true if the class implements the specified interface. Checks the base class (as | |
165 | * identified in the specification), but <em>also</em> accounts for any additional interfaces | |
166 | * that may be added by {@link #extendMethodImplementation(Class, MethodSignature, String)}. | |
167 | */ | |
168 | ||
169 | public boolean implementsInterface(Class interfaceClass); | |
170 | } |
|