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Start your free trialBinyamin Friedman
14,615 Pointsjava.lang.NullPointerException: null at com.teamtreehouse.giflib.service.GifServiceImpl.save
When I try updating a GIF, I get an error page that says:
org.springframework.web.util.NestedServletException: Request processing failed; nested exception is java.lang.NullPointerException
In the run task I have:
java.lang.NullPointerException: null
at com.teamtreehouse.giflib.service.GifServiceImpl.save(GifServiceImpl.java:30) ~[main/:na]
at com.teamtreehouse.giflib.web.controller.GifController.updateGif(GifController.java:101) ~[main/:na]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_131]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_131]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_131]
at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_131]
at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:221) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:136) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:110) ~[spring-webmvc-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:817) ~[spring-webmvc-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:731) ~[spring-webmvc-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85) ~[spring-webmvc-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:959) ~[spring-webmvc-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:893) ~[spring-webmvc-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:968) ~[spring-webmvc-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:870) ~[spring-webmvc-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:648) ~[tomcat-embed-core-8.0.32.jar:8.0.32]
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:844) ~[spring-webmvc-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:729) ~[tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:292) ~[tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207) ~[tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) ~[tomcat-embed-websocket-8.0.32.jar:8.0.32]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240) ~[tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207) ~[tomcat-embed-core-8.0.32.jar:8.0.32]
at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240) ~[tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207) ~[tomcat-embed-core-8.0.32.jar:8.0.32]
at org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:87) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240) ~[tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207) ~[tomcat-embed-core-8.0.32.jar:8.0.32]
at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:77) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240) ~[tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207) ~[tomcat-embed-core-8.0.32.jar:8.0.32]
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:121) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240) ~[tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207) ~[tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:212) ~[tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106) [tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502) [tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:141) [tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79) [tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88) [tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:522) [tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1095) [tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:672) [tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1500) [tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1456) [tomcat-embed-core-8.0.32.jar:8.0.32]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [na:1.8.0_131]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [na:1.8.0_131]
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-8.0.32.jar:8.0.32]
at java.lang.Thread.run(Thread.java:748) [na:1.8.0_131]
My GifController.java:
package com.teamtreehouse.giflib.web.controller;
import com.teamtreehouse.giflib.model.Gif;
import com.teamtreehouse.giflib.service.CategoryService;
import com.teamtreehouse.giflib.service.GifService;
import com.teamtreehouse.giflib.web.FlashMessage;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.validation.BindingResult;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.multipart.MultipartFile;
import org.springframework.web.servlet.mvc.support.RedirectAttributes;
import javax.validation.Valid;
import java.util.ArrayList;
import java.util.List;
@Controller
public class GifController {
@Autowired
private GifService gifService;
@Autowired
private CategoryService categoryService;
// Home page - index of all GIFs
@RequestMapping("/")
public String listGifs(Model model) {
List<Gif> gifs = gifService.findAll();
model.addAttribute("gifs", gifs);
return "gif/index";
}
// Single GIF page
@RequestMapping("/gifs/{gifId}")
public String gifDetails(@PathVariable Long gifId, Model model) {
Gif gif = gifService.findById(gifId);
model.addAttribute("gif", gif);
return "gif/details";
}
// GIF image data
@RequestMapping("/gifs/{gifId}.gif")
@ResponseBody
public byte[] gifImage(@PathVariable Long gifId) {
return gifService.findById(gifId).getBytes();
}
// Favorites - index of all GIFs marked favorite
@RequestMapping("/favorites")
public String favorites(Model model) {
// TODO: Get list of all GIFs marked as favorite
List<Gif> faves = new ArrayList<>();
model.addAttribute("gifs",faves);
model.addAttribute("username","Chris Ramacciotti"); // Static username
return "gif/favorites";
}
// Upload a new GIF
@RequestMapping(value = "/gifs", method = RequestMethod.POST)
public String addGif(Gif gif, @RequestParam MultipartFile file, RedirectAttributes redirectAttributes) {
gifService.save(gif, file);
redirectAttributes.addFlashAttribute("flash", new FlashMessage("GIF successfully uploaded!", FlashMessage.Status.SUCCESS));
return String.format("redirect:/gifs/%s", gif.getId());
}
// Form for uploading a new GIF
@RequestMapping("/upload")
public String formNewGif(Model model) {
if(!model.containsAttribute("gif")) {
model.addAttribute("gif", new Gif());
}
model.addAttribute("categories", categoryService.findAll());
model.addAttribute("title", "Upload");
model.addAttribute("subtitle", "Upload GIFs to share with friends!");
model.addAttribute("action", "/gifs");
model.addAttribute("submit", "Add");
return "gif/form";
}
// Form for editing an existing GIF
@RequestMapping(value = "/gifs/{gifId}/edit")
public String formEditGif(@PathVariable Long gifId, Model model) {
if(!model.containsAttribute("gif")) {
model.addAttribute("gif", gifService.findById(gifId));
}
model.addAttribute("categories", categoryService.findAll());
model.addAttribute("title", "Edit");
model.addAttribute("subtitle", "Edit a GIF!");
model.addAttribute("action", String.format("/gifs/%s", gifId));
model.addAttribute("submit", "Update");
return "gif/form";
}
// Update an existing GIF
@RequestMapping(value = "/gifs/{gifId}", method = RequestMethod.POST)
public String updateGif(Gif gif, RedirectAttributes redirectAttributes, @PathVariable Long gifId, MultipartFile multipartFile) {
gifService.save(gif, multipartFile);
redirectAttributes.addFlashAttribute("flash", new FlashMessage("Update Successful!", FlashMessage.Status.SUCCESS));
return String.format("redirect:/gifs/%s/edit", gifId);
}
// Delete an existing GIF
@RequestMapping(value = "/gifs/{gifId}/delete", method = RequestMethod.POST)
public String deleteGif(@PathVariable Long gifId) {
// TODO: Delete the GIF whose id is gifId
// TODO: Redirect to app root
return null;
}
// Mark/unmark an existing GIF as a favorite
@RequestMapping(value = "/gifs/{gifId}/favorite", method = RequestMethod.POST)
public String toggleFavorite(@PathVariable Long gifId) {
// TODO: With GIF whose id is gifId, toggle the favorite field
// TODO: Redirect to GIF's detail view
return null;
}
// Search results
@RequestMapping("/search")
public String searchResults(@RequestParam String q, Model model) {
// TODO: Get list of GIFs whose description contains value specified by q
List<Gif> gifs = new ArrayList<>();
model.addAttribute("gifs",gifs);
return "gif/index";
}
}
My GIF service implementation is the same as the one Chris has.