displaytag slf4j dependency and spring tests errors - spring

Question

i have problems with my spring tests and displaytag dependency in pom.
my pom dependencies are
<dependencies>
<dependency>
<groupId>org.entando.entando.bundles.misc</groupId>
<artifactId>entando-misc-less</artifactId>
<version>${entando.version}</version>
<type>war</type>
</dependency>
<dependency>
<groupId>org.entando.entando.bundles.misc</groupId>
<artifactId>entando-misc-bootstrap</artifactId>
<version>${entando.version}</version>
<type>war</type>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>org.entando.entando.bundles.pages</groupId>
<artifactId>entando-page-bootstrap-hero</artifactId>
<version>${entando.version}</version>
<type>war</type>
</dependency>
<dependency>
<groupId>org.entando.entando</groupId>
<artifactId>entando-core-webapp</artifactId>
<version>${entando.version}</version>
<type>war</type>
</dependency>
<dependency>
<groupId>org.entando.entando</groupId>
<artifactId>entando-core-engine</artifactId>
<version>${entando.version}</version>
<type>jar</type>
<scope>provided</scope>
<exclusions>
<exclusion>
<artifactId>javassist</artifactId>
<groupId>javassist</groupId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>org.entando.entando</groupId>
<artifactId>entando-core-engine</artifactId>
<version>${entando.version}</version>
<type>test-jar</type>
<scope>test</scope>
</dependency>
<dependency>
<groupId>javax.servlet.jsp</groupId>
<artifactId>jsp-api</artifactId>
<version>2.2</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>servlet-api</artifactId>
<version>2.5</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-test</artifactId>
<version>${spring.version}</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>postgresql</groupId>
<artifactId>postgresql</artifactId>
<version>9.1-901.jdbc4</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.apache.derby</groupId>
<artifactId>derby</artifactId>
<version>10.8.2.2</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.apache.derby</groupId>
<artifactId>derbyclient</artifactId>
<version>10.8.2.2</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.8.2</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.eclipse.persistence</groupId>
<artifactId>eclipselink</artifactId>
<version>2.5.1</version>
</dependency>
<dependency>
<groupId>javax.annotation</groupId>
<artifactId>jsr250-api</artifactId>
<version>1.0</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>javax.persistence</groupId>
<artifactId>persistence-api</artifactId>
<version>1.0</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>javax.transaction</groupId>
<artifactId>jta</artifactId>
<version>1.1</version>
<scope>provided</scope>
</dependency>
<!-- STRUTS2 annotation -->
<dependency>
<groupId>org.apache.struts</groupId>
<artifactId>struts2-convention-plugin</artifactId>
<version>2.3.16.3</version>
</dependency>
<!-- STRUTS2 SPRING integration -->
<dependency>
<groupId>org.apache.struts</groupId>
<artifactId>struts2-spring-plugin</artifactId>
<version>2.3.15.1</version>
</dependency>
<dependency>
<groupId>org.apache.struts</groupId>
<artifactId>struts-taglib</artifactId>
<version>1.3.10</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-tx</artifactId>
<version>3.2.5.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-orm</artifactId>
<version>3.2.5.RELEASE</version>
</dependency>
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-entitymanager</artifactId>
<version>4.3.5.Final</version>
</dependency>
<dependency>
<groupId>org.hibernate.javax.persistence</groupId>
<artifactId>hibernate-jpa-2.1-api</artifactId>
<version>1.0.0.Final</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
<version>2.0.8</version>
</dependency>
<dependency>
<groupId>org.javassist</groupId>
<artifactId>javassist</artifactId>
<version>3.17.1-GA</version>
</dependency>
<dependency>
<groupId>org.apache.struts</groupId>
<artifactId>struts2-junit-plugin</artifactId>
<version>2.3.16.3</version>
</dependency>
<dependency>
<groupId>displaytag</groupId>
<artifactId>displaytag</artifactId>
<version>1.2</version>
<exclusions>
<exclusion>
<artifactId>slf4j-log4j12</artifactId>
<groupId>org.slf4j</groupId>
</exclusion>
</exclusions>
</dependency>
<!-- import ed export -->
<dependency>
<groupId>com.lowagie</groupId>
<artifactId>itext</artifactId>
<version>2.1.7</version>
</dependency>
<dependency>
<groupId>org.xhtmlrenderer</groupId>
<artifactId>flying-saucer-core</artifactId>
<version>9.0.6</version>
</dependency>
<dependency>
<groupId>org.xhtmlrenderer</groupId>
<artifactId>flying-saucer-pdf</artifactId>
<version>9.0.6</version>
</dependency>
</dependencies>
and i wrote some tests for dao, such as
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration(locations = {
"classpath:META-INF/openMED-context-test.xml"
})
public class TestAddressBookJpaController {
/**
* Esegue il test sul load
*/
#Test
public void testLoadAll() {
List<AddressBook> list = this.addressBookDAO.findAddressBookEntities();
Assert.assertNotNull(list);
Assert.assertEquals(22, list.size());
}
when i run tests i get this error
org.slf4j.spi.LocationAwareLogger.log(Lorg/slf4j/Marker;Ljava/lang/String;ILjava/lang/String;Ljava/lang/Throwable;)V
java.lang.NoSuchMethodError
at org.apache.commons.logging.impl.SLF4JLocationAwareLog.error(SLF4JLocationAwareLog.java:173)
at org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:314)
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.createTest(SpringJUnit4ClassRunner.java:211)
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner$1.runReflectiveCall(SpringJUnit4ClassRunner.java:288)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15)
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.methodBlock(SpringJUnit4ClassRunner.java:284)
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:231)
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:88)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:193)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:52)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:191)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:42)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:184)
at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:71)
at org.junit.runners.ParentRunner.run(ParentRunner.java:236)
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:174)
at org.junit.runners.Suite.runChild(Suite.java:128)
at org.junit.runners.Suite.runChild(Suite.java:24)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:193)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:52)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:191)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:42)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:184)
at org.junit.runners.ParentRunner.run(ParentRunner.java:236)
at org.apache.maven.surefire.junit4.JUnit4Provider.execute(JUnit4Provider.java:252)
at org.apache.maven.surefire.junit4.JUnit4Provider.executeTestSet(JUnit4Provider.java:141)
at org.apache.maven.surefire.junit4.JUnit4Provider.invoke(JUnit4Provider.java:112)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.maven.surefire.util.ReflectionUtils.invokeMethodWithArray(ReflectionUtils.java:189)
at org.apache.maven.surefire.booter.ProviderFactory$ProviderProxy.invoke(ProviderFactory.java:165)
at org.apache.maven.surefire.booter.ProviderFactory.invokeProvider(ProviderFactory.java:85)
at org.apache.maven.surefire.booter.ForkedBooter.runSuitesInProcess(ForkedBooter.java:115)
at org.apache.maven.surefire.booter.ForkedBooter.main(ForkedBooter.java:75)
but if i remove the displaytag dependency from pom all work....
What's happening? I can't find the problem :-(
thanks
andrea

Answer 1

This error is due to the fact that you have multiple versions of the same class in your classpath. Typically this is caused by two dependencies which in turn each has a dependency to the same library, but with different versions.
In order to deal with this, run a mvn dependency:tree (mvn dependency:tree > tree.txt if your project is large). Then find all dependencies to the library in question (slf4j), and see what versions are there.
When you've found the version you want to keep (typically the highest), do:
<dependency>
<groupId>library.that</groupId>
<artifactId>i.want</artifactId>
<version>The.right.version</version>
(This will override any transitive dependencies for this library to be the version specified.)
Alternatively, you can exclude the library in the dependency which has a transitive to the version you don't want:
<dependency>
<groupId>library.with</groupId>
<artifactId>bad.transitive.dependency</artifactId>
<version>some.version</version>
<exclusions>
<exclusion>
<groupId>library.that</groupId>
<artifactId>i.want</artifactId>
</exclusion>
</exclusions>
This way, the transitive dependency for this library will be ignored.