title: Liquibase generate changelog from JPA entities
body: <p>I have a Spring boot, spring data jpa project with a parent and three children modules.
  One of my modules is responsible for my JPA entities.
  I need generate one xml changelog with liquibase from this entities.</p>
  
  <p>In my liquibase.properties i have the code:</p>
  
  <pre><code>changeLogFile=src/main/resources/db/changelog/db.changelog-master.xml
  url=jdbc:mysql://localhost:3306/test
  username=root
  password=root
  driver=com.mysql.jdbc.Driver
  outputChangeLogFile=src/main/resources/db/outputChangeLog/liquibase-outputChangeLog.xml
  referenceUrl=hibernate:spring:br.com.company.vacation.domain?dialect=org.hibernate.dialect.MySQLDialect
  diffChangeLogFile=src/main/resources/liquibase-diff-changeLog.xml
  </code></pre>
  
  <p>So, if i try execute the command: <strong>liquibase:diff</strong> i receive the error:</p>
  
  <p>In my pom.xml i configured the liquibase just like this:</p>
  
  <pre><code>&lt;plugin&gt;
      &lt;groupId&gt;org.liquibase&lt;/groupId&gt;
      &lt;artifactId&gt;liquibase-maven-plugin&lt;/artifactId&gt;
      &lt;version&gt;3.4.1&lt;/version&gt;
      &lt;configuration&gt;
          &lt;propertyFile&gt;src/main/resources/liquibase.properties&lt;/propertyFile&gt;
      &lt;/configuration&gt;
          &lt;dependencies&gt;
              &lt;dependency&gt;
                  &lt;groupId&gt;org.liquibase.ext&lt;/groupId&gt;
                  &lt;artifactId&gt;liquibase-hibernate4&lt;/artifactId&gt;
                  &lt;version&gt;3.5&lt;/version&gt;
              &lt;/dependency&gt;
              &lt;dependency&gt;
                  &lt;groupId&gt;org.springframework&lt;/groupId&gt;
                  &lt;artifactId&gt;spring-beans&lt;/artifactId&gt;
                  &lt;version&gt;4.1.7.RELEASE&lt;/version&gt;
              &lt;/dependency&gt;
          &lt;/dependencies&gt;
  &lt;/plugin&gt;
  </code></pre>
  
  <p>If i execute the <strong>liquibase:generateChangeLog</strong> the liquibase generate the log from my existing database...
  But if i tried execute <strong>liquibase:diff</strong> i receive the error:</p>
  
  <pre><code>[ERROR] Failed to execute goal org.liquibase:liquibase-maven-plugin:3.4.1:diff (default-cli) on project vacation-club-web: Execution default-cli of goal org.liquibase:liquibase-maven-plugin:3.4.1:diff failed: A required class was missing while executing org.liquibase:liquibase-maven-plugin:3.4.1:diff: org/springframework/orm/jpa/persistenceunit/DefaultPersistenceUnitManager
  [ERROR] -----------------------------------------------------
  [ERROR] realm =    plugin&gt;org.liquibase:liquibase-maven-plugin:3.4.1
  [ERROR] strategy = org.codehaus.plexus.classworlds.strategy.SelfFirstStrategy
  [ERROR] urls[0] = file:/C:/Users/lucas.araujo/.m2/repository/org/liquibase/liquibase-maven-plugin/3.4.1/liquibase-maven-plugin-3.4.1.jar
  [ERROR] urls[1] = file:/C:/Users/lucas.araujo/.m2/repository/org/liquibase/ext/liquibase-hibernate4/3.5/liquibase-hibernate4-3.5.jar
  [ERROR] urls[2] = file:/C:/Users/lucas.araujo/.m2/repository/org/hibernate/hibernate-core/4.3.1.Final/hibernate-core-4.3.1.Final.jar
  [ERROR] urls[3] = file:/C:/Users/lucas.araujo/.m2/repository/org/jboss/logging/jboss-logging/3.1.3.GA/jboss-logging-3.1.3.GA.jar
  [ERROR] urls[4] = file:/C:/Users/lucas.araujo/.m2/repository/org/jboss/logging/jboss-logging-annotations/1.2.0.Beta1/jboss-logging-annotations-1.2.0.Beta1.jar
  [ERROR] urls[5] = file:/C:/Users/lucas.araujo/.m2/repository/org/jboss/spec/javax/transaction/jboss-transaction-api_1.2_spec/1.0.0.Final/jboss-transaction-api_1.2_spec-1.0.0.Final.jar
  [ERROR] urls[6] = file:/C:/Users/lucas.araujo/.m2/repository/dom4j/dom4j/1.6.1/dom4j-1.6.1.jar
  [ERROR] urls[7] = file:/C:/Users/lucas.araujo/.m2/repository/xml-apis/xml-apis/1.0.b2/xml-apis-1.0.b2.jar
  [ERROR] urls[8] = file:/C:/Users/lucas.araujo/.m2/repository/org/hibernate/common/hibernate-commons-annotations/4.0.4.Final/hibernate-commons-annotations-4.0.4.Final.jar
  [ERROR] urls[9] = file:/C:/Users/lucas.araujo/.m2/repository/org/hibernate/javax/persistence/hibernate-jpa-2.1-api/1.0.0.Final/hibernate-jpa-2.1-api-1.0.0.Final.jar
  [ERROR] urls[10] = file:/C:/Users/lucas.araujo/.m2/repository/org/javassist/javassist/3.18.1-GA/javassist-3.18.1-GA.jar
  [ERROR] urls[11] = file:/C:/Users/lucas.araujo/.m2/repository/antlr/antlr/2.7.7/antlr-2.7.7.jar
  [ERROR] urls[12] = file:/C:/Users/lucas.araujo/.m2/repository/org/jboss/jandex/1.1.0.Final/jandex-1.1.0.Final.jar
  [ERROR] urls[13] = file:/C:/Users/lucas.araujo/.m2/repository/org/hibernate/javax/persistence/hibernate-jpa-2.0-api/1.0.1.Final/hibernate-jpa-2.0-api-1.0.1.Final.jar
  [ERROR] urls[14] = file:/C:/Users/lucas.araujo/.m2/repository/org/hibernate/hibernate-entitymanager/4.3.1.Final/hibernate-entitymanager-4.3.1.Final.jar
  [ERROR] urls[15] = file:/C:/Users/lucas.araujo/.m2/repository/org/hibernate/hibernate-envers/4.3.1.Final/hibernate-envers-4.3.1.Final.jar
  [ERROR] urls[16] = file:/C:/Users/lucas.araujo/.m2/repository/org/springframework/spring-beans/4.1.7.RELEASE/spring-beans-4.1.7.RELEASE.jar
  [ERROR] urls[17] = file:/C:/Users/lucas.araujo/.m2/repository/org/springframework/spring-core/4.1.7.RELEASE/spring-core-4.1.7.RELEASE.jar
  [ERROR] urls[18] = file:/C:/Users/lucas.araujo/.m2/repository/commons-logging/commons-logging/1.2/commons-logging-1.2.jar
  [ERROR] urls[19] = file:/C:/Users/lucas.araujo/.m2/repository/org/codehaus/plexus/plexus-utils/1.0.4/plexus-utils-1.0.4.jar
  [ERROR] urls[20] = file:/C:/Users/lucas.araujo/.m2/repository/org/liquibase/liquibase-core/3.4.1/liquibase-core-3.4.1.jar
  [ERROR] Number of foreign imports: 1
  [ERROR] import: Entry[import  from realm ClassRealm[maven.api, parent: null]]
  [ERROR] 
  [ERROR] -----------------------------------------------------: org.springframework.orm.jpa.persistenceunit.DefaultPersistenceUnitManager
  </code></pre>
  
  <p>Someone already had this problem?</p>