1 | // SECTION-START[License Header] |
2 | // <editor-fold defaultstate="collapsed" desc=" Generated License "> |
3 | /* |
4 | * Java Object Management and Configuration |
5 | * Copyright (C) Christian Schulte, 2005-206 |
6 | * All rights reserved. |
7 | * |
8 | * Redistribution and use in source and binary forms, with or without |
9 | * modification, are permitted provided that the following conditions |
10 | * are met: |
11 | * |
12 | * o Redistributions of source code must retain the above copyright |
13 | * notice, this list of conditions and the following disclaimer. |
14 | * |
15 | * o Redistributions in binary form must reproduce the above copyright |
16 | * notice, this list of conditions and the following disclaimer in |
17 | * the documentation and/or other materials provided with the |
18 | * distribution. |
19 | * |
20 | * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, |
21 | * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY |
22 | * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL |
23 | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY DIRECT, INDIRECT, |
24 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
25 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
26 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
27 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
28 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
29 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
30 | * |
31 | * $JOMC: DefaultInvoker.java 4795 2013-04-21 09:09:02Z schulte $ |
32 | * |
33 | */ |
34 | // </editor-fold> |
35 | // SECTION-END |
36 | package org.jomc.ri; |
37 | |
38 | import java.lang.reflect.InvocationTargetException; |
39 | import org.jomc.model.Instance; |
40 | import org.jomc.spi.Invocation; |
41 | import org.jomc.spi.Invoker; |
42 | |
43 | // SECTION-START[Documentation] |
44 | // <editor-fold defaultstate="collapsed" desc=" Generated Documentation "> |
45 | /** |
46 | * Default {@code Invoker} implementation. |
47 | * |
48 | * <dl> |
49 | * <dt><b>Identifier:</b></dt><dd>org.jomc.ri.DefaultInvoker</dd> |
50 | * <dt><b>Name:</b></dt><dd>JOMC ⁑ RI ⁑ DefaultInvoker</dd> |
51 | * <dt><b>Abstract:</b></dt><dd>No</dd> |
52 | * <dt><b>Final:</b></dt><dd>No</dd> |
53 | * <dt><b>Stateless:</b></dt><dd>No</dd> |
54 | * </dl> |
55 | * |
56 | * @author <a href="mailto:cs@schulte.it">Christian Schulte</a> 1.0 |
57 | * @version 1.0 |
58 | */ |
59 | // </editor-fold> |
60 | // SECTION-END |
61 | // SECTION-START[Annotations] |
62 | // <editor-fold defaultstate="collapsed" desc=" Generated Annotations "> |
63 | @javax.annotation.Generated( value = "org.jomc.tools.SourceFileProcessor 1.5", comments = "See http://www.jomc.org/jomc/1.5/jomc-tools-1.5" ) |
64 | // </editor-fold> |
65 | // SECTION-END |
66 | public class DefaultInvoker implements Invoker |
67 | { |
68 | // SECTION-START[DefaultInvoker] |
69 | |
70 | /** |
71 | * Performs a method invocation on an object. |
72 | * <p>This method first passes the given invocation to the {@code preInvoke} method. If the result property of the |
73 | * invocation returned by the {@code preInvoke} method is an instance of {@code Throwable}, that instance will be |
74 | * thrown; otherwise the invocation returned by the {@code preInvoke} method is performed and then passed to the |
75 | * {@code postInvoke} method. If the result property of the invocation returned from the {@code postInvoke} method |
76 | * is an instance of {@code Throwable}, that instance will be thrown; otherwise the value of the result property is |
77 | * returned by this method.</p> |
78 | * |
79 | * @param invocation The invocation to perform. |
80 | * |
81 | * @return The return value of the invocation. If the declared return type of the method of the invocation is a |
82 | * primitive type, then the value returned by this method must be an instance of the corresponding primitive wrapper |
83 | * class; otherwise, it must be a type assignable to the declared return type of the method of the invocation. |
84 | * If the value returned by this method is {@code null} and the declared return type of the method of the invocation |
85 | * is primitive, then a {@code NullPointerException} will be thrown. If the value returned by this method is |
86 | * otherwise not compatible to the declared return type of the method of the invocation, a |
87 | * {@code ClassCastException} will be thrown. |
88 | * |
89 | * @throws Throwable The exception thrown from the method invocation. The exception's type must be assignable |
90 | * either to any of the exception types declared in the {@code throws} clause of the method of the invocation or to |
91 | * the unchecked exception types {@code java.lang.RuntimeException} or {@code java.lang.Error}. |
92 | * If a checked exception is thrown by this method that is not assignable to any of the exception types declared in |
93 | * the {@code throws} clause of the method of the invocation, then an {@code UndeclaredThrowableException} |
94 | * containing the exception that was thrown by this method will be thrown. |
95 | * |
96 | * @see #preInvoke(org.jomc.spi.Invocation) |
97 | * @see #postInvoke(org.jomc.spi.Invocation) |
98 | */ |
99 | public Object invoke( final Invocation invocation ) throws Throwable |
100 | { |
101 | Invocation current = invocation; |
102 | final Instance instance = (Instance) current.getContext().get( DefaultInvocation.INSTANCE_KEY ); |
103 | |
104 | try |
105 | { |
106 | if ( instance != null && instance.isStateless() ) |
107 | { |
108 | try |
109 | { |
110 | current = this.preInvoke( current ); |
111 | } |
112 | catch ( final Throwable t ) |
113 | { |
114 | this.handleException( current, t ); |
115 | } |
116 | |
117 | if ( !( current.getResult() instanceof Throwable ) ) |
118 | { |
119 | try |
120 | { |
121 | current.setResult( current.getMethod().invoke( current.getObject(), current.getArguments() ) ); |
122 | } |
123 | catch ( final Throwable t ) |
124 | { |
125 | this.handleException( current, t ); |
126 | } |
127 | } |
128 | |
129 | try |
130 | { |
131 | current = this.postInvoke( current ); |
132 | } |
133 | catch ( final Throwable t ) |
134 | { |
135 | this.handleException( current, t ); |
136 | } |
137 | |
138 | if ( current.getResult() instanceof Throwable ) |
139 | { |
140 | throw (Throwable) current.getResult(); |
141 | } |
142 | |
143 | return current.getResult(); |
144 | } |
145 | else |
146 | { |
147 | synchronized ( invocation.getObject() ) |
148 | { |
149 | try |
150 | { |
151 | current = this.preInvoke( current ); |
152 | } |
153 | catch ( final Throwable t ) |
154 | { |
155 | this.handleException( current, t ); |
156 | } |
157 | |
158 | if ( !( current.getResult() instanceof Throwable ) ) |
159 | { |
160 | try |
161 | { |
162 | current.setResult( current.getMethod().invoke( current.getObject(), |
163 | current.getArguments() ) ); |
164 | |
165 | } |
166 | catch ( final Throwable t ) |
167 | { |
168 | this.handleException( current, t ); |
169 | } |
170 | } |
171 | |
172 | try |
173 | { |
174 | current = this.postInvoke( current ); |
175 | } |
176 | catch ( final Throwable t ) |
177 | { |
178 | this.handleException( current, t ); |
179 | } |
180 | |
181 | if ( current.getResult() instanceof Throwable ) |
182 | { |
183 | throw (Throwable) current.getResult(); |
184 | } |
185 | |
186 | return current.getResult(); |
187 | } |
188 | } |
189 | } |
190 | finally |
191 | { |
192 | invocation.getContext().clear(); |
193 | } |
194 | } |
195 | |
196 | /** |
197 | * Called before an invocation is performed. |
198 | * <p>Overriding classes may use this method to perform any kind of operation prior to an invocation and to create |
199 | * custom invocation instances. If an overriding class wishes to throw an exception, it may do so by setting the |
200 | * result property of the returned invocation to an instance of {@code Throwable} thrown as the result of the |
201 | * invocation. If an overriding class wishes to provide a custom {@code Invocation} class, it may do so by returning |
202 | * a different instance from this method. By default, this method does nothing and returns the given invocation |
203 | * unchanged.</p> |
204 | * |
205 | * @param invocation The invocation about to be performed. |
206 | * |
207 | * @return The processed invocation. |
208 | * |
209 | * @throws NullPointerException if {@code invocation} is {@code null}. |
210 | */ |
211 | public Invocation preInvoke( final Invocation invocation ) |
212 | { |
213 | if ( invocation == null ) |
214 | { |
215 | throw new NullPointerException( "invocation" ); |
216 | } |
217 | |
218 | return invocation; |
219 | } |
220 | |
221 | /** |
222 | * Called after an invocation has been performed. |
223 | * <p>Overriding classes may use this method to perform any kind of operation after an invocation has been |
224 | * performed and to maintain custom invocation instances. If an overriding class wishes to throw an exception, it |
225 | * may do so by setting the result property of the returned invocation to an instance of {@code Throwable} thrown as |
226 | * the result of the invocation. Since the result property of the given invocation already holds the result of the |
227 | * invocation (which may already be an instance of {@code Throwable}), care must be taken when updating that result. |
228 | * By default, this method does nothing and returns the given invocation unchanged.</p> |
229 | * |
230 | * @param invocation The performed invocation. |
231 | * |
232 | * @return The processed invocation. |
233 | * |
234 | * @throws NullPointerException if {@code invocation} is {@code null}. |
235 | */ |
236 | public Invocation postInvoke( final Invocation invocation ) |
237 | { |
238 | if ( invocation == null ) |
239 | { |
240 | throw new NullPointerException( "invocation" ); |
241 | } |
242 | |
243 | return invocation; |
244 | } |
245 | |
246 | /** |
247 | * Called whenever an exception has been caught. |
248 | * <p>Overriding classes may use this method for handling exceptions. By default, this method updates the result of |
249 | * the given invocation with the given throwable. If that throwable is an instance of |
250 | * {@code InvocationTargetException}, this method updates the result with the value of that exception's target |
251 | * exception. If the result of the given invocation already is an instance of {@code Throwable}, this method does |
252 | * not update the result.</p> |
253 | * |
254 | * @param invocation The invocation to update. |
255 | * @param t The throwable to update {@code invocation} with. |
256 | */ |
257 | public void handleException( final Invocation invocation, final Throwable t ) |
258 | { |
259 | if ( invocation != null && !( invocation.getResult() instanceof Throwable ) ) |
260 | { |
261 | if ( t instanceof InvocationTargetException |
262 | && ( (InvocationTargetException) t ).getTargetException() != null ) |
263 | { |
264 | invocation.setResult( ( (InvocationTargetException) t ).getTargetException() ); |
265 | return; |
266 | } |
267 | |
268 | invocation.setResult( t ); |
269 | } |
270 | } |
271 | |
272 | // SECTION-END |
273 | // SECTION-START[Constructors] |
274 | // <editor-fold defaultstate="collapsed" desc=" Generated Constructors "> |
275 | /** Creates a new {@code DefaultInvoker} instance. */ |
276 | @javax.annotation.Generated( value = "org.jomc.tools.SourceFileProcessor 1.5", comments = "See http://www.jomc.org/jomc/1.5/jomc-tools-1.5" ) |
277 | public DefaultInvoker() |
278 | { |
279 | // SECTION-START[Default Constructor] |
280 | super(); |
281 | // SECTION-END |
282 | } |
283 | // </editor-fold> |
284 | // SECTION-END |
285 | // SECTION-START[Dependencies] |
286 | // SECTION-END |
287 | // SECTION-START[Properties] |
288 | // SECTION-END |
289 | // SECTION-START[Messages] |
290 | // SECTION-END |
291 | } |