自动装配时控制器为空

Question

我有一个名为ReportController的控制器，它可以成功地访问存储库中的数据。我在另一个处理WebSocket消息的类中自动连接了该类，因为我还想在数据库之间发送WebSocket消息。然而，问题是，当我在SocketHandler类中自动连接控制器类并从那里调用方法时，它会给出一个空指针异常。我已经用@组件或@服务注释了控制器，但没有成功。我的课程如下

package com.labafrique.creporter;

import com.labafrique.creporter.property.FileStorageProperties;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.context.properties.EnableConfigurationProperties;
import org.springframework.context.annotation.ComponentScan;

@EnableConfigurationProperties({
        FileStorageProperties.class
})
@SpringBootApplication

public class CreporterApplication {

    public static void main(String[] args) {
        SpringApplication.run(CreporterApplication.class, args);
    }

}

我的控制器类

/*
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 * and open the template in the editor.
 */
package com.labafrique.creporter.controller;

import com.google.gson.Gson;
import com.labafrique.creporter.model.ReportModel;
import com.labafrique.creporter.repository.ReportRepository;
import com.labafrique.creporter.service.FileStorageService;
import java.io.File;
import java.io.IOException;
import java.net.URLDecoder;
import java.net.URLEncoder;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import javax.servlet.http.HttpServletRequest;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.core.io.Resource;
import org.springframework.http.HttpHeaders;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.stereotype.Service;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

/**
 *
 * @author Javalove
 */

@Service
@RestController
@RequestMapping("/creporter/listener")
public class ReportController {

    @Autowired
    private ReportRepository caseRepo;

    @Autowired
    private FileStorageService fileStorageService;



    private static final Logger logger = LoggerFactory.getLogger(ReportController.class);


    @GetMapping(path="/getCases")
    @ResponseBody
    public String getCases(@RequestParam("t") String type, @RequestParam("x") String x)
    {
        return URLDecoder.decode(new Gson().toJson(caseRepo.findByCaseType(type, Integer.parseInt(x))));
    }

    @GetMapping(path="/getSent")
    @ResponseBody
    public String getSent(@RequestParam("sender") String sender, @RequestParam("email") String email, @RequestParam("phone") String phone, @RequestParam("type") String type)
    {
        try
        {
            email = URLEncoder.encode(email, "utf-8");
            sender = URLEncoder.encode(sender, "utf-8");
            phone = URLEncoder.encode(phone, "utf-8");
            type = URLEncoder.encode(type, "utf-8");
        }catch(Exception er){}
        return URLDecoder.decode(new Gson().toJson(caseRepo.getSent(sender, email, phone, type)));
    }


    @PostMapping(path="/add")
    @ResponseBody
    public String save(@RequestParam("code") String code, @RequestParam("category") String category, 
            @RequestParam("details") String details, 
            @RequestParam("audio") String audio, 
            @RequestParam("video") String video,
            @RequestParam("photo") String photo, 
            @RequestParam("address") String address, @RequestParam("rtype") String rtype, 
            @RequestParam("caseLocation") String caseLocation, 
            @RequestParam("userLocation") String userLocation,
            @RequestParam("photoFile") MultipartFile photoFile, 
            @RequestParam("videoFile") MultipartFile videoFile, 
            @RequestParam ("audioFile") MultipartFile audioFile,
            @RequestParam("email") String email,
            @RequestParam("phone") String phone,
            @RequestParam("sender") String sender,
            @RequestParam("thumb") String thumb)

    {
        String uploadingDir = System.getProperty("user.dir")+"/CReporterUploads/";
        System.out.println(uploadingDir);
        String result = "error";
        ReportModel model = new ReportModel();
        model.setAddress(address);
        model.setCaseLocation(caseLocation); 
        model.setCategory(category);
        model.setCode(code);
        model.setAudio(audio);
        model.setVideo(video);
        model.setPhoto(photo);
        model.setDetails(details);
        model.setRtype(rtype);
        model.setEmail(email);
        model.setSender(sender);
        model.setPhone(phone);
        model.setThumb(Integer.parseInt(thumb));
        model.setUserLocation(userLocation);
        if(audio.equals("true") )
        {
            doUpload(uploadingDir, audioFile, code);
        }
        if(video.equals("true") )
        {
            doUpload(uploadingDir, videoFile, code);
        }
        if(photo.equals("true") )
        {
            doUpload(uploadingDir, photoFile, code);
        }
        ReportModel md = caseRepo.save(model);
        /*
        if(attachment != null && attachment.length > 0)
        {
            logger.info("i'm in bro");
            uploadM(attachment, code);
        }
        */


        return new Gson().toJson(model);


    }

    @PostMapping(path = "/thmbUp")
    public void vote(@RequestParam("code") String code)
    {
        caseRepo.ThumbUp(code);
    }

    @GetMapping(path = "/welcome")
    public String getPage()
    {
        return "mapping";
    }




    public boolean doUpload(String uploadingDir, MultipartFile uploadedFile, String code)
    {
        System.out.println("about to upload photo");
        boolean done = false;
        File f = new File(uploadingDir +code + "/");
        if(!f.exists())
        {
            f.mkdirs();
        }
        try
        {
            File file = new File(uploadingDir + "/"+code + "/" +uploadedFile.getOriginalFilename());
            uploadedFile.transferTo(file);
        }
        catch(IOException er)
        {
            er.printStackTrace();
        }
        return done;
    }


    @GetMapping(path = "/test")
    public String test()
    {
        try{
        String uploadingDir1 = System.getProperty("user.dir") + "/creporter/";
        Path path = Paths.get(uploadingDir1);

        if (!Files.exists(path)) {

            Files.createDirectory(path);
            return("Directory created");
        } else {

            return("Directory already exists");
        }
        }catch(Exception er){return er.getMessage();}
    }




    @GetMapping("/getFile/{fileName:.+}")
    public ResponseEntity<Resource> downloadFile(@PathVariable String fileName, HttpServletRequest request) {
        // Load file as Resource
        String a[] = fileName.split("_");
        Resource resource = fileStorageService.loadFileAsResource(a[1], a[0]);

        // Try to determine file's content type
        String contentType = null;
        try {
            contentType = request.getServletContext().getMimeType(resource.getFile().getAbsolutePath());
        } catch (IOException ex) {
            logger.info("Could not determine file type.");
        }

        // Fallback to the default content type if type could not be determined
        if(contentType == null) {
            contentType = "application/octet-stream";
        }

        return ResponseEntity.ok()
                .contentType(MediaType.parseMediaType(contentType))
                .header(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=\"" + resource.getFilename() + "\"")
                .body(resource);
    }




}

和我的套接字处理程序类

package com.labafrique.creporter.controller;

import com.labafrique.creporter.controller.ReportController;
import com.labafrique.creporter.repository.ReportRepository;
import org.springframework.stereotype.Component;
import org.springframework.web.socket.TextMessage;
import org.springframework.web.socket.WebSocketSession;
import org.springframework.web.socket.handler.TextWebSocketHandler;

import java.io.IOException;
import java.util.List;
import java.util.concurrent.CopyOnWriteArrayList;
import org.springframework.beans.factory.annotation.Autowired;

@Component
public class SocketHandler extends TextWebSocketHandler  {


        @Autowired
        ReportController report;




    List<WebSocketSession> sessions = new CopyOnWriteArrayList<>();

    @Override
    public void handleTextMessage(WebSocketSession session, TextMessage message)
            {
        //Map<String, String> value = new Gson().fromJson(message.getPayload(), Map.class);
        /*for(WebSocketSession webSocketSession : sessions) {
            webSocketSession.sendMessage(new TextMessage("Hello " + value.get("name") + " !"));
        }*/
            //session.sendMessage(new TextMessage("Hello " + value.get("name") + " !"));
                            try
                            {
                        System.out.println(message.getPayload());
                        session.sendMessage(new TextMessage("i received "+message));
                String t[] = message.getPayload().split("##");
                //try {session.sendMessage(new TextMessage(control.test())); }
                //catch(Exception ee){session.sendMessage(new TextMessage(ee.getMessage()));}
                session.sendMessage(new TextMessage("alldata##"+report.getCases("cor", "0")));
                if(message.getPayload().startsWith("AllData"))
                {
                    //System.out.println(control.("cor", "0"));
                    //session.sendMessage(new TextMessage("alldata##"+report.findByCaseType("cor", Integer.parseInt(t[1]))));
                }
                            }
                            catch(Exception er)
                            {
                                er.printStackTrace();
                            }
    }

    @Override
    public void afterConnectionEstablished(WebSocketSession session) throws Exception {
        //the messages will be broadcasted to all users.
                session.sendMessage(new TextMessage("welcomeBro##xx"));
                //session.sendMessage(new TextMessage("alldata##"+report.findByCaseType("cor", 0)));
                //session.sendMessage(new TextMessage(control.test()));
        sessions.add(session);
    }

        public void sendLatest(String latest)
        {
            for(WebSocketSession webSocketSession : sessions) 
            {
                try
                {
                webSocketSession.sendMessage(new TextMessage("latest##"+latest));
                }catch(Exception er)
                {}
            }
        }

}

Answer 1

哇...经过将近一周的调试，我发现了问题......在我的Websocketconfig类中，我创建了一个新的SocketHandler实例，这就是导致问题的原因...所以我将我的配置类更改为

@Autowired
SocketHandler handler;

public void registerWebSocketHandlers(WebSocketHandlerRegistry registry) {
    registry.addHandler(handler, "/socket");
}

最初，我在register方法中有了新的SocketHandler（）。我希望这对某人有所帮助。

Answer 2

你可以这样做。

@Service
public class ServiceBean {

    public String getCases(String type, String x)
    {
        return URLDecoder.decode(new Gson().toJson(caseRepo.findByCaseType(type, Integer.parseInt(x))));
    }
}

@RestController
@RequestMapping("/creporter/listener")
public class ReportController {

    @Autowired
    private ReportRepository caseRepo;

    @Autowired
    private FileStorageService fileStorageService;

    @Autowired
    private ServiceBean serviceBean;

    @GetMapping(path="/getCases")

    @ResponseBody
    public String getCases(@RequestParam("t") String type, @RequestParam("x") String x)
    {
        return serviceBean.getCase(type, x);
    }
}

@Component
public class SocketHandler extends TextWebSocketHandler  {

    @Autowired
    private ServiceBean serviceBean;

    // do here anything you want with methods of serviceBean
}