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50 <header><h1>Known Pitfalls (FAQ)</h1></header>
56 <h2>Annotated classes in dependencies are not found.<a name="Annotated_classes_in_dependencies_are_not_found."></a></h2>
59 hibernate4-maven-plugin by default scans dependencies in the scope
60 <tt>compile</tt>. You can configure it to scan dependencies in other
61 scopes as well. But it scans only direct dependencies. Transitive
62 dependencies are not scanned for annotated classes. If some of your
63 annotated classes are hidden in a transitive dependency, you can simply
64 add that dependency explicitly.
68 <h2>hibernate4-maven-plugin always needs a database-connection<a name="hibernate4-maven-plugin_always_needs_a_database-connection"></a></h2>
71 The default-configuration uses the EXPORT-target of the SchemaExport-Tool.
72 If you do not need to create a database with the evaluated schema, you can
73 use the NONE- or the SCRIPT-target.
74 This can be achieved with the command-line parameter
75 <tt>-Dhibernate.export.target=SCRIPT</tt> or with the following configuration:
79 <pre class="prettyprint linenums lang-html">
81 <target>SCRIPT</target>
82 </configuration></pre></div>
85 But even when no database is to be created, hibernate always needs to know
86 the dialect. Hence, the plugin will fail if this parameter is missing!
90 <h2>Dependency for driver-class XYZ is missing<a name="Dependency_for_driver-class_XYZ_is_missing"></a></h2>
93 One regular problem is the scope of the jdbc-driver-dependency.
94 It is very unlikely, that this dependency is needed at compile-time.
95 So a tidy maven-developer would usually scope it for <tt>runtime</tt>.
99 But this will break the execution of the <tt>hibernate4-maven-plugin</tt>.
100 Since it will not be able to see the needed dependency, it will fail with
101 an error-message like:
105 <pre class="prettyprint">
106 [INFO] Gathered hibernate-configuration (turn on debugging for details):
107 [INFO] hibernate.connection.username = sa
108 [INFO] hibernate.connection.password =
109 [INFO] hibernate.dialect = org.hibernate.dialect.HSQLDialect
110 [INFO] hibernate.connection.url = jdbc:hsqldb:/home/kai/mmf/target/mmf;shutdown=true
111 [INFO] hibernate.connection.driver_class = org.hsqldb.jdbcDriver
112 [ERROR] Dependency for driver-class org.hsqldb.jdbcDriver is missing!
113 [INFO] ------------------------------------------------------------------------
115 [INFO] ------------------------------------------------------------------------
116 [INFO] org.hsqldb.jdbcDriver
117 [INFO] ------------------------------------------------------------------------
118 [INFO] For more information, run Maven with the -e switch
119 [INFO] ------------------------------------------------------------------------
120 [INFO] Total time: 2 seconds
121 [INFO] Finished at: Thu Nov 29 11:31:14 CET 2012
122 [INFO] Final Memory: 32M/342M
123 [INFO] ------------------------------------------------------------------------</pre></div>
126 A quick workaround for this error would be, to delete the runtime-constraint
127 for the jdbc-driver-dependency.
131 A much cleaner way is, to (additionally) ad the dependency, to the
136 <pre class="prettyprint linenums lang-html">
138 <groupId>de.juplo</groupId>
139 <artifactId>hibernate4-maven-plugin</artifactId>
140 <version>1.0.4</version>
144 <goal>export</goal>
150 <groupId>org.hsqldb</groupId>
151 <artifactId>hsqldb</artifactId>
152 <version>2.2.8</version>
154 </dependencies>
155 </plugin></pre></div>
158 This is also the best way, if you use a different jdbc-driver for
159 testing, than in production.
160 Because otherwise, this dependency will unnecessarily bloat the
161 runtime-dependencies of your project.
164 <div class="section" id="fails">
165 <h2 id="fails">DBUnit fails after execution of hibernate4 was skipped because nothing has changed</h2>
168 If hibernate4-maven-plugin skips its excecution, this may lead to errors in
170 For example, when importing sample-data in the automatically created database
171 with the help of the <a class="externalLink" href="http://mojo.codehaus.org/dbunit-maven-plugin/">dbunit-plugin</a>,
172 the <tt>CLEAN_INSERT</tt>-operation may fail because of foreign-key-constraints,
173 if the database was not recreated, because the hibernate4-maven-plugin has
174 skipped its excecution.
178 A quick fix to this problem is, to <a href="./force.html">force</a>
179 hibernate4-maven-plugin to export the schema every time it is running.
180 But to recreate the database on every testrun may noticeable slow down your
181 development cycle, if you have to wait for slow IO.
185 To circumvent this problem, hibernate4-maven-plugin signals a skipped
186 excecution by setting the maven property <tt>$\{hibernate.export.skipped\}</tt> to
188 You can configure other plugins to react on this signal.
189 For example, the dbunit-plugin can be configured to skip its excecution, if
190 hibernate4-maven-plugin was skipped like this:
194 <pre class="prettyprint linenums lang-html">
196 <groupId>org.codehaus.mojo</groupId>
197 <artifactId>dbunit-maven-plugin</artifactId>
198 <configuration>
199 <skip>${hibernate.export.skipped}</skip>
200 </configuration>
201 </plugin></pre></div>
203 <div class="section">
204 <h2>The database will not be recreated after a manual drop/clean<a name="The_database_will_not_be_recreated_after_a_manual_dropclean"></a></h2>
207 If one manually drops the database or removes the hsqldb-files, it will not
208 be recreated by the hibernate4-maven-plugin, because it cannot detect, that
209 the database needs to be recreated.
210 This happens, because the plugin will not recreate the database if neither
211 the configuration nor the annotated classes have changed, because an
212 unnecessary drop-create-cycle might take a long time. The plugin will
213 report that like this:
217 <pre class="prettyprint">
218 [INFO] No modified annotated classes found and dialect unchanged.
219 [INFO] Skipping schema generation!</pre></div>
222 If one always uses <tt>mvn clean</tt> for cleanup, this will not happen.
223 Otherwise the recreation must be <a href="./force.html">forced</a>:
227 <pre class="prettyprint">
228 mvn hibernate4:export -Dhibernate.export.force=true</pre></div>
230 <div class="section">
231 <h2>The hibernate4:export goal is not executed, when tests are skipped<a name="The_hibernate4:export_goal_is_not_executed_when_tests_are_skipped"></a></h2>
234 The hibernate4-maven-plugin automatically skips its execution, when
235 <tt>maven.test.skip</tt> is set to <tt>true</tt>. If you need it to be always
236 executed, you can configure that explicitly like this:
240 <pre class="prettyprint linenums lang-html">
242 <groupId>de.juplo</groupId>
243 <artifactId>hibernate4-maven-plugin</artifactId>
245 <configuration>
246 <skip>false</skip>
247 </configuration>
248 </plugin></pre></div>
251 Background-information for this design-decission can be found on the extra
252 page <a href="./skip.html">To skip or not to skip: that is the question</a>...
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