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  49
  50   <div class="section"><h2>Annotated classes in dependencies are not found.<a name="Annotated_classes_in_dependencies_are_not_found."></a></h2>
  51   <p>
  52   hibernate-maven-plugin by default scans dependencies in the scope
  53   <tt>compile</tt>. You can configure it to scan dependencies in other
  54   scopes as well. But it scans only direct dependencies. Transitive
  55   dependencies are not scanned for annotated classes. If some of your
  56   annotated classes are hidden in a transitive dependency, you can simply
  57   add that dependency explicitly.
  58   </p>
  59   </div><div class="section"><h2>hibernate-maven-plugin always needs a database-connection<a name="hibernate-maven-plugin_always_needs_a_database-connection"></a></h2>
  60   <p>
  61   The default-configuration uses the EXPORT-target of the SchemaExport-Tool.
  62   If you do not need to create a database with the evaluated schema, you can
  63   use the NONE- or the SCRIPT-target.
  64   This can be achieved with the command-line parameter
  65   <tt>-Dhibernate.export.target=SCRIPT</tt> or with the following configuration:
  66   </p>
  67   <div class="prettyprint linenums lang-html"><pre>
  68 &lt;configuration&gt;
  69   &lt;target&gt;SCRIPT&lt;/target&gt;
  70 &lt;/configuration&gt;</pre></div>
  71   <p>
  72   But even when no database is to be created, hibernate always needs to know
  73   the dialect. Hence, the plugin will fail if this parameter is missing!
  74   </p>
  75   </div><div class="section"><h2>Dependency for driver-class XYZ is missing<a name="Dependency_for_driver-class_XYZ_is_missing"></a></h2>
  76   <p>
  77   One regular problem is the scope of the jdbc-driver-dependency.
  78   It is very unlikely, that this dependency is needed at compile-time.
  79   So a tidy maven-developer would usually scope it for <tt>runtime</tt>.
  80   </p>
  81   <p>
  82   But this will break the execution of the <tt>hibernate-maven-plugin</tt>.
  83   Since it will not be able to see the needed dependency, it will fail with
  84   an error-message like:
  85   </p>
  86   <div class="prettyprint"><pre>
  87 [INFO] Gathered hibernate-configuration (turn on debugging for details):
  88 [INFO]   hibernate.connection.username = sa
  89 [INFO]   hibernate.connection.password =
  90 [INFO]   hibernate.dialect = org.hibernate.dialect.HSQLDialect
  91 [INFO]   hibernate.connection.url = jdbc:hsqldb:/home/kai/mmf/target/mmf;shutdown=true
  92 [INFO]   hibernate.connection.driver_class = org.hsqldb.jdbcDriver
  93 [ERROR] Dependency for driver-class org.hsqldb.jdbcDriver is missing!
  94 [INFO] ------------------------------------------------------------------------
  95 [ERROR] BUILD ERROR
  96 [INFO] ------------------------------------------------------------------------
  97 [INFO] org.hsqldb.jdbcDriver
  98 [INFO] ------------------------------------------------------------------------
  99 [INFO] For more information, run Maven with the -e switch
 100 [INFO] ------------------------------------------------------------------------
 101 [INFO] Total time: 2 seconds
 102 [INFO] Finished at: Thu Nov 29 11:31:14 CET 2012
 103 [INFO] Final Memory: 32M/342M
 104 [INFO] ------------------------------------------------------------------------</pre></div>
 105   <p>
 106   A quick workaround for this error would be, to delete the runtime-constraint
 107   for the jdbc-driver-dependency.
 108   </p>
 109   <p>
 110   A much cleaner way is, to (additionally) ad the dependency, to the
 111   plugin-definition:
 112   </p>
 113   <div class="prettyprint linenums lang-html"><pre>
 114 &lt;plugin&gt;
 115   &lt;groupId&gt;de.juplo&lt;/groupId&gt;
 116   &lt;artifactId&gt;hibernate-maven-plugin&lt;/artifactId&gt;
 117   &lt;version&gt;${project.version}&lt;/version&gt;
 118   &lt;executions&gt;
 119     &lt;execution&gt;
 120       &lt;goals&gt;
 121         &lt;goal&gt;export&lt;/goal&gt;
 122       &lt;/goals&gt;
 123     &lt;/execution&gt;
 124   &lt;/executions&gt;
 125   &lt;dependencies&gt;
 126   &lt;dependency&gt;
 127     &lt;groupId&gt;org.hsqldb&lt;/groupId&gt;
 128     &lt;artifactId&gt;hsqldb&lt;/artifactId&gt;
 129     &lt;version&gt;2.2.8&lt;/version&gt;
 130   &lt;/dependency&gt;
 131   &lt;/dependencies&gt;
 132 &lt;/plugin&gt;</pre></div>
 133   <p>
 134   This is also the best way, if you use a different jdbc-driver for
 135   testing, than in production.
 136   Because otherwise, this dependency will unnecessarily bloat the
 137   runtime-dependencies of your project.
 138   </p>
 139   </div><div class="section"><h2 id="fails">DBUnit fails after execution of hibernate was skipped because nothing has changed</h2>
 140   <p>
 141   If hibernate-maven-plugin skips its excecution, this may lead to errors in
 142   other plugins.
 143   For example, when importing sample-data in the automatically created database
 144   with the help of the <a class="externalLink" href="http://mojo.codehaus.org/dbunit-maven-plugin/">dbunit-plugin</a>,
 145   the <tt>CLEAN_INSERT</tt>-operation may fail because of foreign-key-constraints,
 146   if the database was not recreated, because the hibernate-maven-plugin has
 147   skipped its excecution.
 148   </p>
 149   <p>
 150   A quick fix to this problem is, to <a href="./force.html">force</a>
 151   hibernate-maven-plugin to export the schema every time it is running.
 152   But to recreate the database on every testrun may noticeable slow down your
 153   development cycle, if you have to wait for slow IO.
 154   </p>
 155   <p>
 156   To circumvent this problem, hibernate-maven-plugin signals a skipped
 157   excecution by setting the  maven property <tt>$\{hibernate.export.skipped\}</tt> to
 158   <tt>true</tt>.
 159   You can configure other plugins to react on this signal.
 160   For example, the dbunit-plugin can be configured to skip its excecution, if
 161   hibernate-maven-plugin was skipped like this:
 162   </p>
 163   <div class="prettyprint linenums lang-html"><pre>
 164 &lt;plugin&gt;
 165   &lt;groupId&gt;org.codehaus.mojo&lt;/groupId&gt;
 166   &lt;artifactId&gt;dbunit-maven-plugin&lt;/artifactId&gt;
 167   &lt;configuration&gt;
 168     &lt;skip&gt;${hibernate.export.skipped}&lt;/skip&gt;
 169   &lt;/configuration&gt;
 170 &lt;/plugin&gt;</pre></div>
 171   </div><div class="section"><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>
 172   <p>
 173   If one manually drops the database or removes the hsqldb-files, it will not
 174   be recreated by the hibernate-maven-plugin, because it cannot detect, that
 175   the database needs to be recreated.
 176   This happens, because the plugin will not recreate the database if neither
 177   the configuration nor the annotated classes have changed, because an
 178   unnecessary drop-create-cycle might take a long time. The plugin will
 179   report that like this:
 180   </p>
 181   <div class="prettyprint"><pre>
 182 [INFO] No modified annotated classes found and dialect unchanged.
 183 [INFO] Skipping schema generation!</pre></div>
 184   <p>
 185   If one always uses <tt>mvn clean</tt> for cleanup, this will not happen.
 186   Otherwise the recreation must be <a href="./force.html">forced</a>:
 187   </p>
 188   <div class="prettyprint"><pre>
 189 mvn hibernate:export -Dhibernate.export.force=true</pre></div>
 190   </div><div class="section"><h2>The hibernate:export goal is not executed, when tests are skipped<a name="The_hibernate:export_goal_is_not_executed_when_tests_are_skipped"></a></h2>
 191   <p>
 192   The hibernate-maven-plugin automatically skips its execution, when
 193   <tt>maven.test.skip</tt> is set to <tt>true</tt>. If you need it to be always
 194   executed, you can configure that explicitly like this:
 195   </p>
 196   <div class="prettyprint linenums lang-html"><pre>
 197 &lt;plugin&gt;
 198   &lt;groupId&gt;de.juplo&lt;/groupId&gt;
 199   &lt;artifactId&gt;hibernate-maven-plugin&lt;/artifactId&gt;
 200   ...
 201   &lt;configuration&gt;
 202     &lt;skip&gt;false&lt;/skip&gt;
 203   &lt;/configuration&gt;
 204 &lt;/plugin&gt;</pre></div>
 205   <p>
 206   Background-information for this design-decission can be found on the extra
 207   page <a href="./skip.html">To skip or not to skip: that is the question</a>...
 208   </p>
 209   </div><div class="section"><h2>I do not want my dependencies to be scanned for hibernate annotations<a name="I_do_not_want_my_dependencies_to_be_scanned_for_hibernate_annotations"></a></h2>
 210   <p>
 211     If you do not want your dependencies to be scanned for hibernate annotations,
 212     you can pass <tt>-Dhibernate.export.scan_dependencies=none</tt> to maven
 213     or set <tt>scanDependencies</tt> to <tt>none</tt> in the configuration
 214     of the plugin like this:
 215   </p>
 216   <div class="prettyprint linenums lang-html"><pre>
 217 &lt;plugin&gt;
 218   &lt;groupId&gt;de.juplo&lt;/groupId&gt;
 219   &lt;artifactId&gt;hibernate-maven-plugin&lt;/artifactId&gt;
 220   ...
 221   &lt;configuration&gt;
 222     &lt;scanDependencies&gt;none&lt;/scanDependencies&gt;
 223   &lt;/configuration&gt;
 224 &lt;/plugin&gt;</pre></div>
 225   </div><div class="section"><h2>No annotated classes found<a name="No_annotated_classes_found"></a></h2>
 226   <p>
 227     If you are working under Windows and get the error-message
 228     <tt>No annotated classes found in directory C:\projects\X Y Z\path-to-project\target\classes</tt>,
 229     but you are really sure, that there are annotated classes in that
 230     directory, you are expiriencing a bug, in the scannotation-library, that
 231     was closed in version 1.1.0 of the hibernate-maven-plugin.
 232   </p>
 233   <p>
 234     <b>
 235       You should consider to upgrade to that version of the plugin.
 236     </b>
 237   </p>
 238  </div>
 239
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