Spring Data JPA repository throws null pointer
<p>I've been working with Spring Data with Spring Boot. With the JavaConfig documentation I have set up a Spring JPA configuration, but when calling the save method in my repository a null pointer is thrown. </p>

<p>My repository:</p>

<pre><code>import org.springframework.data.jpa.repository.JpaRepository;

public interface HouseRepository extends JpaRepository&lt;House, Long&gt; {
}
</code></pre>

<p>My POJO's:</p>

<p>AbstractHouse</p>

<pre><code>@MappedSuperclass
@Table(name="houses")
@Inheritance(strategy=InheritanceType.SINGLE_TABLE)
public abstract class AbstractHouse implements Serializable {

@NotEmpty
private String houseName;

@NotEmpty
private String houseNumber;
</code></pre>

<p>House</p>

<pre><code>@Entity
public class SmallHouse extends AbstractHouse {

@Id
@GeneratedValue
private Long id;

private Date created;

private Date updated;
</code></pre>

<p>I've then got a service object that takes an Autowired repository and attempts to save using methods obtained through JPA:</p>

<pre><code>@Service
public class HouseService {

@Autowired
protected HouseRepository houseRepository;

public void save(House house) {
    houseRepository.save(house);
} 
</code></pre>

<p>My application class contains:</p>

<pre><code>@SpringBootApplication
@EnableScheduling
@EnableJpaRepositories
public class Application {

public static void main(String[] args) throws Exception {
    SpringApplication.run(Application.class, args);
}
}
</code></pre>

<p>I am fairly new to Spring Data, so I do think its something within the configuration that I am missing, any advice would be greatly appreciated!</p>

<p>--Update--</p>

<p>Stack Trace:</p>

<pre><code>java.lang.NullPointerException
    at com.jm.service.HouseService.save(HouseService.java:15)
    at com.jm.service.HouseClass.gatherHouses(HouseClass.java:43)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:221)
    at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:137)
    at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:110)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:775)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:705)
    at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85)
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:959)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:893)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:967)
    at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:858)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:622)
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:843)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:291)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:77)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:85)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:217)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:142)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:518)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1091)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:673)
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1500)
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1456)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    at java.lang.Thread.run(Thread.java:745)
</code></pre>

<p>And I call the method as such:</p>

<pre><code>public class HouseMain {

    @Autowired
    public HouseService houseService;

    public void gatherHouse() {
    houseService = new HouseService();
    House h = new House();
    h.setHouseName("House1");
    h.setHouseNumber("12");
    try {

        HouseService.save(vmComp);          
        }
    } catch (Exception e) {
        e.printStackTrace();
    }
}
}
</code></pre>

<p>Then in my controller I am calling house.gatherHouse</p>