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7 <h2>Annotated classes in dependencies are not found.</h2>
9 hibernate4-maven-plugin by default scans dependencies in the scope
10 <code>compile</code>. You can configure it to scan dependencies in other
11 scopes as well. But it scans only direct dependencies. Transitive
12 dependencies are not scanned for annotated classes. If some of your
13 annotated classes are hidden in a transitive dependency, you can simply
14 add that dependency explicitly.
16 <h2>hibernate4-maven-plugin always needs a database-connection</h2>
18 The default-configuration uses the EXPORT-target of the SchemaExport-Tool.
19 If you do not need to create a database with the evaluated schema, you can
20 use the NONE- or the SCRIPT-target.
21 This can be achieved with the command-line parameter
22 <code>-Dhibernate.export.target=SCRIPT</code> or with the following configuration:
24 <pre class="prettyprint linenums lang-html">
26 <target>SCRIPT</target>
27 </configuration></pre>
29 But even when no database is to be created, hibernate always needs to know
30 the dialect. Hence, the plugin will fail if this parameter is missing!
32 <h2>Dependency for driver-class XYZ is missing</h2>
34 One regular problem is the scope of the jdbc-driver-dependency.
35 It is very unlikely, that this dependency is needed at compile-time.
36 So a tidy maven-developer would usually scope it for <code>runtime</code>.
39 But this will break the execution of the <code>hibernate4-maven-plugin</code>.
40 Since it will not be able to see the needed dependency, it will fail with
41 an error-message like:
43 <pre class="prettyprint">
44 [INFO] Gathered hibernate-configuration (turn on debugging for details):
45 [INFO] hibernate.connection.username = sa
46 [INFO] hibernate.connection.password =
47 [INFO] hibernate.dialect = org.hibernate.dialect.HSQLDialect
48 [INFO] hibernate.connection.url = jdbc:hsqldb:/home/kai/mmf/target/mmf;shutdown=true
49 [INFO] hibernate.connection.driver_class = org.hsqldb.jdbcDriver
50 [ERROR] Dependency for driver-class org.hsqldb.jdbcDriver is missing!
51 [INFO] ------------------------------------------------------------------------
53 [INFO] ------------------------------------------------------------------------
54 [INFO] org.hsqldb.jdbcDriver
55 [INFO] ------------------------------------------------------------------------
56 [INFO] For more information, run Maven with the -e switch
57 [INFO] ------------------------------------------------------------------------
58 [INFO] Total time: 2 seconds
59 [INFO] Finished at: Thu Nov 29 11:31:14 CET 2012
60 [INFO] Final Memory: 32M/342M
61 [INFO] ------------------------------------------------------------------------</pre>
63 A quick workaround for this error would be, to delete the runtime-constraint
64 for the jdbc-driver-dependency.
67 A much cleaner way is, to (additionally) ad the dependency, to the
70 <pre class="prettyprint linenums lang-html">
72 <groupId>de.juplo</groupId>
73 <artifactId>hibernate4-maven-plugin</artifactId>
74 <version>${project.version}</version>
78 <goal>export</goal>
84 <groupId>org.hsqldb</groupId>
85 <artifactId>hsqldb</artifactId>
86 <version>2.2.8</version>
91 This is also the best way, if you use a different jdbc-driver for
92 testing, than in production.
93 Because otherwise, this dependency will unnecessarily bloat the
94 runtime-dependencies of your project.
96 <h2 id="fails">DBUnit fails after execution of hibernate4 was skipped because nothing has changed</h2>
98 If hibernate4-maven-plugin skips its excecution, this may lead to errors in
100 For example, when importing sample-data in the automatically created database
101 with the help of the <a href="http://mojo.codehaus.org/dbunit-maven-plugin/">dbunit-plugin</a>,
102 the <code>CLEAN_INSERT</code>-operation may fail because of foreign-key-constraints,
103 if the database was not recreated, because the hibernate4-maven-plugin has
104 skipped its excecution.
107 A quick fix to this problem is, to <a href="./force.html">force</a>
108 hibernate4-maven-plugin to export the schema every time it is running.
109 But to recreate the database on every testrun may noticeable slow down your
110 development cycle, if you have to wait for slow IO.
113 To circumvent this problem, hibernate4-maven-plugin signals a skipped
114 excecution by setting the maven property <code>$\{hibernate.export.skipped\}</code> to
116 You can configure other plugins to react on this signal.
117 For example, the dbunit-plugin can be configured to skip its excecution, if
118 hibernate4-maven-plugin was skipped like this:
120 <pre class="prettyprint linenums lang-html">
122 <groupId>org.codehaus.mojo</groupId>
123 <artifactId>dbunit-maven-plugin</artifactId>
124 <configuration>
125 <skip>${hibernate.export.skipped}</skip>
126 </configuration>
127 </plugin></pre>
128 <h2>The database will not be recreated after a manual drop/clean</h2>
130 If one manually drops the database or removes the hsqldb-files, it will not
131 be recreated by the hibernate4-maven-plugin, because it cannot detect, that
132 the database needs to be recreated.
133 This happens, because the plugin will not recreate the database if neither
134 the configuration nor the annotated classes have changed, because an
135 unnecessary drop-create-cycle might take a long time. The plugin will
136 report that like this:
138 <pre class="prettyprint">
139 [INFO] No modified annotated classes found and dialect unchanged.
140 [INFO] Skipping schema generation!</pre>
142 If one always uses <code>mvn clean</code> for cleanup, this will not happen.
143 Otherwise the recreation must be <a href="./force.html">forced</a>:
145 <pre class="prettyprint">
146 mvn hibernate4:export -Dhibernate.export.force=true</pre>
147 <h2>The hibernate4:export goal is not executed, when tests are skipped</h2>
149 The hibernate4-maven-plugin automatically skips its execution, when
150 <code>maven.test.skip</code> is set to <code>true</code>. If you need it to be always
151 executed, you can configure that explicitly like this:
153 <pre class="prettyprint linenums lang-html">
155 <groupId>de.juplo</groupId>
156 <artifactId>hibernate4-maven-plugin</artifactId>
158 <configuration>
159 <skip>false</skip>
160 </configuration>
161 </plugin></pre>
163 Background-information for this design-decission can be found on the extra
164 page <a href="./skip.html">To skip or not to skip: that is the question</a>...
166 <h2>I do not want my dependencies to be scanned for hibernate annotations</h2>
168 If you do not want your dependencies to be scanned for hibernate annotations,
169 you can pass <code>-Dhibernate.export.scan_dependencies=none</code> to maven
170 or set <code>scanDependencies</code> to <code>none</code> in the configuration
171 of the plugin like this:
173 <pre class="prettyprint linenums lang-html">
175 <groupId>de.juplo</groupId>
176 <artifactId>hibernate4-maven-plugin</artifactId>
178 <configuration>
179 <scanDependencies>none</scanDependencies>
180 </configuration>
181 </plugin></pre>
182 <h2>No annotated classes found</h2>
184 If you are working under Windows and get the error-message
185 <code>No annotated classes found in directory C:\projects\X Y Z\path-to-project\target\classes</code>,
186 but you are really sure, that there are annotated classes in that
187 directory, you are expiriencing a bug, in the scannotation-library, that
188 was closed in version 1.1.0 of the hibernate-maven-plugin.
192 You should consider to upgrade to that version of the plugin.