Problems with testing JdbcDao by DBUnit

Question

I have AuthorJDBCDAO class with basic CRUD methods which extends AbstractJDBCDAO class and implements AuthorDAO interface. I tested all methods via psv main() method and everything was fine. But Now I have to test it's methods using DBUnit. And here my troubles start. I try to test just only create() method and it isn't working properly. I'm using Unitils, Spring DI, Oracle DB to create my application. I inject bean DataSource(dbcp2) to bean AuthorJDBCDAO . I use XML configuration for injection beans. Here's my source code and configuration files. Test class.

@SpringApplicationContext({"spring-test-config.xml"})
@DataSet(value = "AuthorDAOTest.xml", loadStrategy =       CleanInsertLoadStrategy.class)
public class AuthorDAOTest extends UnitilsJUnit4 {

@SpringBean("authorJDBCDAO")
private AuthorJDBCDAO authorDAO;

@Test
public void testCreate() throws DAOException {
    Author expected = new Author();
    expected.setName("BLABLABLA");
    expected.setExpiredDate(Timestamp.valueOf(LocalDateTime.now()));
    Author result = null;


    result = authorDAO.create(expected);

    assertEquals(expected.getId(), result.getId());
    System.out.println("Hello from test");
}

Here's stacktrace from execution of Test class.

newsportal.exception.DAOException: java.sql.SQLException: Connection is null.
at newsportal.dao.impl.AbstractJDBCDAO.create(AbstractJDBCDAO.java:115)
at com.epam.ivanou.newsportal.dao.impl.AuthorJDBCDAOTest.testCreate(AuthorJDBCDAOTest.java:33)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at org.junit.internal.runners.TestMethod.invoke(TestMethod.java:68)
at org.junit.internal.runners.MethodRoadie.runTestMethod(MethodRoadie.java:108)
at org.unitils.UnitilsJUnit4TestClassRunner$TestListenerInvokingMethodRoadie.runTestMethod(UnitilsJUnit4TestClassRunner.java:204)
at org.junit.internal.runners.MethodRoadie$2.run(MethodRoadie.java:89)
at org.junit.internal.runners.MethodRoadie.runBeforesThenTestThenAfters(MethodRoadie.java:97)
at org.unitils.UnitilsJUnit4TestClassRunner$TestListenerInvokingMethodRoadie.runBeforesThenTestThenAfters(UnitilsJUnit4TestClassRunner.java:186)
at org.junit.internal.runners.MethodRoadie.runTest(MethodRoadie.java:87)
at org.junit.internal.runners.MethodRoadie.run(MethodRoadie.java:50)
at org.unitils.UnitilsJUnit4TestClassRunner.invokeTestMethod(UnitilsJUnit4TestClassRunner.java:95)
at org.junit.internal.runners.JUnit4ClassRunner.runMethods(JUnit4ClassRunner.java:59)
at org.unitils.UnitilsJUnit4TestClassRunner.access$000(UnitilsJUnit4TestClassRunner.java:42)
at org.unitils.UnitilsJUnit4TestClassRunner$1.run(UnitilsJUnit4TestClassRunner.java:60)
at org.junit.internal.runners.ClassRoadie.runUnprotected(ClassRoadie.java:34)
at org.junit.internal.runners.ClassRoadie.runProtected(ClassRoadie.java:44)
at org.unitils.UnitilsJUnit4TestClassRunner.run(UnitilsJUnit4TestClassRunner.java:67)
at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:78)
at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:212)
at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:68)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at com.intellij.rt.execution.application.AppMain.main(AppMain.java:140)
Caused by: java.sql.SQLException: Connection is null.
at org.apache.commons.dbcp2.DelegatingConnection.checkOpen(DelegatingConnection.java:608)
at org.apache.commons.dbcp2.DelegatingConnection.prepareStatement(DelegatingConnection.java:286)
at com.epam.ivanou.newsportal.dao.impl.AbstractJDBCDAO.create(AbstractJDBCDAO.java:106)
... 29 more

Fragment of code of AbstractJDBCDAO class. In which I get this exception. I tried to debug it and found, that in the second try-catch-with-resources block connection is null. But I can't understand, how does it occur if I try to get connection from DataSource which is BasicDataSource and support connection pooling.

@Override
public T create(T object) throws DAOException {
    T persistInstance;
    // Add the record
    String sql = getCreateQuery();
    String idName = getIdString();
    String tableName = getTableName();

    try (Connection connection = DataSourceUtils.getConnection(dataSource);
         PreparedStatement statement = connection.prepareStatement(sql)) {
        System.out.println("connection: "+ connection + " data source: " + dataSource); 
        prepareStatementForInsert(statement, object);
        int count = statement.executeUpdate();
        if (count != 1) {
            throw new DAOException("On persist modify more then 1 record: " + count);
        }
    } catch (Exception e) {
        throw new DAOException(e);
    }
    // Get recently inserted record
    sql = getSelectQuery() + " WHERE " + idName + " = (SELECT MAX(" + idName + ") FROM "
            + tableName + ")";


    try (Connection connection = DataSourceUtils.getConnection(dataSource);
         PreparedStatement statement = connection.prepareStatement(sql)) //here is connection is null and SQLException is thrown {
        System.out.println("connection: "+ connection + " data source: " + dataSource); //TODO connection is null in test method, but is good when using main() method
        ResultSet rs = statement.executeQuery();
        List<T> list = parseResultSet(rs);
        if ((list == null) || (list.size() != 1)) {
            throw new DAOException("Exception on findByPK new persist data.");
        }
        persistInstance = list.iterator().next();
    } catch (Exception e) {
        throw new DAOException(e);
    }
    return persistInstance;
}

here're configuration files for my beans: dao-beans.xml

<?xml version="1.0" encoding="UTF-8"?>

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans-4.2.xsd">

   <bean id="authorJDBCDAO" class="newsportal.dao.impl.AuthorJDBCDAO">
          <constructor-arg ref="dataSource"/>
   </bean>

database-test-config.xml

<beans xmlns="http://www.springframework.org/schema/beans"
   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   xsi:schemaLocation="http://www.springframework.org/schema/beans
   http://www.springframework.org/schema/beans/spring-beans-4.2.xsd">


<bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
    <property name="location">
        <value>db_test.properties</value>
    </property>
</bean>

<bean id="dataSource" class="org.apache.commons.dbcp2.BasicDataSource" destroy-method="close">
    <property name="driverClassName" value="${jdbc.driverClassName}"/>
    <property name="url" value="${jdbc.url}"/>
    <property name="username" value="${jdbc.username}"/>
    <property name="password" value="${jdbc.password}"/>
    <property name="maxIdle" value="${jdbc.maxIdle}"/>
    <property name="minIdle" value="${jdbc.minIdle}"/>
    <property name="maxWaitMillis" value="${jdbc.maxWaitMillis}"/>
    <property name="initialSize" value="${jdbc.initialSize}"/>
</bean>

<bean id="transactionManager"
      class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
    <property name="dataSource" ref="dataSource" />
</bean>


</beans>

spring-test-config.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   xsi:schemaLocation="http://www.springframework.org/schema/beans
   http://www.springframework.org/schema/beans/spring-beans.xsd">


<import resource="database-test-config.xml" />
<import resource="dao-beans.xml" />

</beans>

db_test.properties

jdbc.driverClassName=oracle.jdbc.driver.OracleDriver
jdbc.url=jdbc:oracle:thin:@localhost:1521:xe
jdbc.username=Yahor_test
jdbc.password=1234
jdbc.maxIdle=100
jdbc.minIdle=10
jdbc.maxWaitMillis=10000
jdbc.initialSize=10

And here's Simple java class for testing:

    public class Test {
    public static void main(String[] args) throws DAOException {
    ApplicationContext ctx = new ClassPathXmlApplicationContext("spring-config.xml");
    AuthorJDBCDAO authorDAO = (AuthorJDBCDAO) ctx.getBean("authorJDBCDAO");

        Author author = new Author();
        author.setName("Yahor");
        author = authorDAO.create(author);
        System.out.println(author.getId());

    }

And it's working fine =) May be smth wrong with transactional configurations in my DBUnit Test class?

Answer 1

Problem is solved. I should close connection via DataSourceUtils.doReleaseConnection(). Otherwise connection will be closed physically. It was the keystone of my trouble.