Btukfyl

I'm trying to @Autowire a @Service in a @Controller. This results in a runtime NullPointerException (where I attempt to make use of the @Service). For some reason Spring isn't injecting the dependency and I'm yet to figure it out. It doesn't seem to be because of the two primary causes (manual instanstiation or lack of annotations).

ReviewController:

package group9.movie_reviews.controller;



import group9.movie_reviews.service.impl.ReviewService;

import org.springframework.stereotype.Controller;

import org.springframework.ui.ModelMap;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.RequestMethod;

import org.springframework.web.bind.annotation.SessionAttributes;



import javax.annotation.Resource;



@Controller

@RequestMapping("/review")

@SessionAttributes("review")

public class ReviewController {



    @Resource

    private ReviewService reviewService;



    @RequestMapping(method = RequestMethod.GET)

    public String wtf(ModelMap model) {

        model.addAttribute("a", reviewService.getReviews()); // NullPointerException here

        return "index";

    }



}

ReviewService:

package group9.movie_reviews.service;



import group9.movie_reviews.model.ReviewEntity;



public interface ReviewService {



    Iterable<ReviewEntity> getReviews();



    void addReview(String movieName);



}

ReviewServiceImpl:

package group9.movie_reviews.service.impl;



import group9.movie_reviews.model.ReviewEntity;

import group9.movie_reviews.repository.ReviewRepository;

import group9.movie_reviews.service.ReviewService;

import org.springframework.stereotype.Service;



import javax.annotation.Resource;



@Service

public class ReviewServiceImpl implements ReviewService {



    @Resource

    private ReviewRepository reviewRepository;



    @Override

    public Iterable<ReviewEntity> getReviews() {

        return reviewRepository.findAll();

    }



    @Override

    public void addReview(String movieName) {

        ReviewEntity r = new ReviewEntity();

        r.setMovieName(movieName);

        reviewRepository.save(r);

    }



}

ReviewRepository:

package group9.movie_reviews.repository;



import group9.movie_reviews.model.ReviewEntity;

import org.springframework.data.jpa.repository.JpaRepository;

import org.springframework.stereotype.Repository;



@Repository

public interface ReviewRepository extends JpaRepository<ReviewEntity, Integer> {

    ReviewEntity findByMovieName(String movieName);

}

Stacktrace/error:

Type Exception Report



Message Request processing failed; nested exception is java.lang.NullPointerException



Description The server encountered an unexpected condition that prevented it from fulfilling the request.



Exception



org.springframework.web.util.NestedServletException: Request processing failed; nested exception is java.lang.NullPointerException

    org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:982)

    org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:861)

    javax.servlet.http.HttpServlet.service(HttpServlet.java:622)

    org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846)

    javax.servlet.http.HttpServlet.service(HttpServlet.java:729)

    org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)



Root Cause



java.lang.NullPointerException

    group9.movie_reviews.controller.ReviewController.wtf(ReviewController.java:21)

    sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

    sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)

    sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)

    java.lang.reflect.Method.invoke(Method.java:498)

    org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:221)

    org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:136)

    org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:114)

    org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:827)

    org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:738)

    org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85)

    org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:963)

    org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:897)

    org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970)

    org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:861)

    javax.servlet.http.HttpServlet.service(HttpServlet.java:622)

    org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846)

    javax.servlet.http.HttpServlet.service(HttpServlet.java:729)

    org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)

Config Files:

WebConfig:

package group9.movie_reviews.config;



import org.springframework.context.annotation.Bean;

import org.springframework.context.annotation.ComponentScan;

import org.springframework.context.annotation.Configuration;

import org.springframework.data.jpa.repository.config.EnableJpaRepositories;

import org.springframework.transaction.annotation.EnableTransactionManagement;

import org.springframework.web.servlet.config.annotation.EnableWebMvc;

import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;

import org.springframework.web.servlet.view.InternalResourceViewResolver;



@Configuration

@EnableWebMvc

@ComponentScan(basePackages = {"group9.movie_reviews"})

@EnableTransactionManagement

@EnableJpaRepositories(basePackages = {"group9.movie_reviews.repository"})

public class WebConfig extends WebMvcConfigurerAdapter {



    @Bean

    public InternalResourceViewResolver resolver() {

        InternalResourceViewResolver resolver = new InternalResourceViewResolver();

        resolver.setPrefix("/WEB-INF/jsp/");

        resolver.setSuffix(".jsp");

        return resolver;

    }



}

WebInit:

package group9.movie_reviews.config;



import org.springframework.context.annotation.Configuration;

import org.springframework.web.servlet.support.AbstractAnnotationConfigDispatcherServletInitializer;



@Configuration

public class WebInit extends AbstractAnnotationConfigDispatcherServletInitializer {



    @Override

    protected Class<?> getRootConfigClasses() {

        return new Class{RootConfig.class};

    }



    @Override

    protected Class<?> getServletConfigClasses() {

        return new Class{WebConfig.class};

    }



    @Override

    protected String getServletMappings() {

        return new String{"/", "/review"};

    }



}

Redeploy exception/stacktrace:

[2018-11-22 02:53:37,857] Artifact movie_reviews:war exploded: Artifact is being deployed, please wait...

22-Nov-2018 02:53:37.878 INFO [RMI TCP Connection(83)-127.0.0.1] org.springframework.web.context.support.AnnotationConfigWebApplicationContext.doClose Closing WebApplicationContext for namespace 'dispatcher-servlet': startup date [    Thu Nov 22 02:35:08 GMT 2018]; parent: Root WebApplicationContext

22-Nov-2018 02:53:37.878 WARNING [RMI TCP Connection(83)-127.0.0.1] org.springframework.web.context.support.AnnotationConfigWebApplicationContext.doClose Exception thrown from LifecycleProcessor on context close

 java.lang.IllegalStateException: LifecycleProcessor not initialized - call 'refresh' before invoking lifecycle methods via the context: WebApplicationContext for namespace 'dispatcher-servlet': startup date [Thu Nov 22 02:35:08 GMT     2018]; parent: Root WebApplicationContext

    at org.springframework.context.support.AbstractApplicationContext.getLifecycleProcessor(AbstractApplicationContext.java:416)

    at org.springframework.context.support.AbstractApplicationContext.doClose(AbstractApplicationContext.java:997)

    at org.springframework.context.support.AbstractApplicationContext.close(AbstractApplicationContext.java:956)

    at org.springframework.web.servlet.FrameworkServlet.destroy(FrameworkServlet.java:829)

    at org.apache.catalina.core.StandardWrapper.unload(StandardWrapper.java:1393)

    at org.apache.catalina.core.StandardWrapper.stopInternal(StandardWrapper.java:1729)

    at org.apache.catalina.util.LifecycleBase.stop(LifecycleBase.java:221)

    at org.apache.catalina.core.StandardContext.stopInternal(StandardContext.java:5573)

    at org.apache.catalina.util.LifecycleBase.stop(LifecycleBase.java:221)

    at org.apache.catalina.core.ContainerBase.removeChild(ContainerBase.java:851)

    at org.apache.catalina.startup.HostConfig.unmanageApp(HostConfig.java:1755)

    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:498)

    at org.apache.tomcat.util.modeler.BaseModelMBean.invoke(BaseModelMBean.java:300)

    at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.invoke(DefaultMBeanServerInterceptor.java:819)

    at com.sun.jmx.mbeanserver.JmxMBeanServer.invoke(JmxMBeanServer.java:801)

    at org.apache.catalina.mbeans.MBeanFactory.removeContext(MBeanFactory.java:792)

    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:498)

    at org.apache.tomcat.util.modeler.BaseModelMBean.invoke(BaseModelMBean.java:300)

    at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.invoke(DefaultMBeanServerInterceptor.java:819)

    at com.sun.jmx.mbeanserver.JmxMBeanServer.invoke(JmxMBeanServer.java:801)

    at javax.management.remote.rmi.RMIConnectionImpl.doOperation(RMIConnectionImpl.java:1468)

    at javax.management.remote.rmi.RMIConnectionImpl.access$300(RMIConnectionImpl.java:76)

    at javax.management.remote.rmi.RMIConnectionImpl$PrivilegedOperation.run(RMIConnectionImpl.java:1309)

    at javax.management.remote.rmi.RMIConnectionImpl.doPrivilegedOperation(RMIConnectionImpl.java:1401)

    at javax.management.remote.rmi.RMIConnectionImpl.invoke(RMIConnectionImpl.java:829)

    at sun.reflect.GeneratedMethodAccessor238.invoke(Unknown Source)

    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)

    at java.lang.reflect.Method.invoke(Method.java:498)

    at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:357)

    at sun.rmi.transport.Transport$1.run(Transport.java:200)

    at sun.rmi.transport.Transport$1.run(Transport.java:197)

    at java.security.AccessController.doPrivileged(Native Method)

    at sun.rmi.transport.Transport.serviceCall(Transport.java:196)

    at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:573)

    at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run0(TCPTransport.java:835)

    at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.lambda$run$0(TCPTransport.java:688)

    at java.security.AccessController.doPrivileged(Native Method)

    at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:687)

    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)

    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)

    at java.lang.Thread.run(Thread.java:748)



22-Nov-2018 02:53:37.880 INFO [RMI TCP Connection(83)-127.0.0.1] org.springframework.web.context.support.AnnotationConfigWebApplicationContext.doClose Closing Root WebApplicationContext: startup date [Thu Nov 22 02:35:08 GMT 2018];     root of context hierarchy

22-Nov-2018 02:53:40.095 INFO [RMI TCP Connection(83)-127.0.0.1] org.apache.jasper.servlet.TldScanner.scanJars At least one JAR was scanned for TLDs yet contained no TLDs. Enable debug logging for this logger for a complete list of     JARs that were scanned but no TLDs were found in them. Skipping unneeded JARs during scanning can improve startup time and JSP compilation time.

22-Nov-2018 02:53:40.197 INFO [RMI TCP Connection(83)-127.0.0.1] org.springframework.web.context.ContextLoader.initWebApplicationContext Root WebApplicationContext: initialization started

22-Nov-2018 02:53:40.305 INFO [RMI TCP Connection(83)-127.0.0.1] org.springframework.web.context.support.AnnotationConfigWebApplicationContext.prepareRefresh Refreshing Root WebApplicationContext: startup date [Thu Nov 22 02:53:40     GMT 2018]; root of context hierarchy

22-Nov-2018 02:53:40.400 INFO [RMI TCP Connection(83)-127.0.0.1] org.springframework.web.context.support.AnnotationConfigWebApplicationContext.loadBeanDefinitions Registering annotated classes: [class     group9.movie_reviews.config.RootConfig]

22-Nov-2018 02:53:40.709 INFO [RMI TCP Connection(83)-127.0.0.1] org.springframework.web.context.ContextLoader.initWebApplicationContext Root WebApplicationContext: initialization completed in 512 ms

22-Nov-2018 02:53:40.713 INFO [RMI TCP Connection(83)-127.0.0.1] org.springframework.web.servlet.DispatcherServlet.initServletBean FrameworkServlet 'dispatcher': initialization started

22-Nov-2018 02:53:40.719 INFO [RMI TCP Connection(83)-127.0.0.1] org.springframework.web.context.support.AnnotationConfigWebApplicationContext.prepareRefresh Refreshing WebApplicationContext for namespace 'dispatcher-servlet':     startup date [Thu Nov 22 02:53:40 GMT 2018]; parent: Root WebApplicationContext

22-Nov-2018 02:53:40.722 INFO [RMI TCP Connection(83)-127.0.0.1] org.springframework.web.context.support.AnnotationConfigWebApplicationContext.loadBeanDefinitions Registering annotated classes: [class     group9.movie_reviews.config.WebConfig]

SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".

SLF4J: Defaulting to no-operation (NOP) logger implementation

SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.

[2018-11-22 02:53:41,443] Artifact movie_reviews:war exploded: Artifact is deployed successfully

[2018-11-22 02:53:41,443] Artifact movie_reviews:war exploded: Deploy took 3,586 milliseconds

Pom.xml:

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

<project xmlns="http://maven.apache.org/POM/4.0.0"

         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">

    <modelVersion>4.0.0</modelVersion>



    <groupId>group9</groupId>

    <artifactId>movie_reviews</artifactId>

    <version>1.0</version>

    <packaging>war</packaging>



    <name>movie_reviews</name>



    <properties>

        <endorsed.dir>${project.build.directory}/endorsed</endorsed.dir>

        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>

        <spring-version>4.3.3.RELEASE</spring-version>

        <servlet-version>3.1.0</servlet-version>

        <jstl-version>1.2</jstl-version>

    </properties>



    <dependencies>

        <dependency>

            <groupId>org.springframework</groupId>

            <artifactId>spring-webmvc</artifactId>

            <version>${spring-version}</version>

        </dependency>

        <dependency>

            <groupId>javax.servlet</groupId>

            <artifactId>javax.servlet-api</artifactId>

            <version>${servlet-version}</version>

            <scope>provided</scope>

        </dependency>

        <dependency>

            <groupId>org.springframework</groupId>

            <artifactId>spring-jdbc</artifactId>

            <version>${spring-version}</version>

        </dependency>

        <dependency>

            <groupId>org.springframework</groupId>

            <artifactId>spring-orm</artifactId>

            <version>${spring-version}</version>

        </dependency>

        <dependency>

            <groupId>org.hibernate</groupId>

            <artifactId>hibernate-core</artifactId>

            <version>5.3.7.Final</version>

        </dependency>

        <dependency>

            <groupId>com.h2database</groupId>

            <artifactId>h2</artifactId>

            <version>1.4.196</version>

        </dependency>

        <dependency>

            <groupId>org.springframework.data</groupId>

            <artifactId>spring-data-jpa</artifactId>

            <version>2.1.2.RELEASE</version>

        </dependency>

        <dependency>

            <groupId>jstl</groupId>

            <artifactId>jstl</artifactId>

            <version>${jstl-version}</version>

        </dependency>

        <dependency>

            <groupId>mysql</groupId>

            <artifactId>mysql-connector-java</artifactId>

            <version>8.0.13</version>

        </dependency>

    </dependencies>



    <build>

        <plugins>

            <plugin>

                <groupId>org.apache.maven.plugins</groupId>

                <artifactId>maven-compiler-plugin</artifactId>

                <version>3.1</version>

                <configuration>

                    <source>1.7</source>

                    <target>1.7</target>

                    <compilerArguments>

                        <endorseddirs>${endorsed.dir}</endorseddirs>

                    </compilerArguments>

                </configuration>

            </plugin>

            <plugin>

                <groupId>org.apache.maven.plugins</groupId>

                <artifactId>maven-war-plugin</artifactId>

                <version>2.3</version>

                <configuration>

                    <failOnMissingWebXml>false</failOnMissingWebXml>

                </configuration>

            </plugin>

        </plugins>

    </build>



</project>