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Vaadin和Spring-@Autowired字段為空

[英]Vaadin and Spring - @Autowired field is null

 原文  2014-06-29 12:38:20  7   1    java/ spring/ vaadin/ autowired/ vaadin4spring

問題描述

我的最后一個問題被標記為重復，但是答案對我不起作用:-(

我在同一包中有兩個類，我需要從@Service中找到對象並打印結果以進行記錄。 

package com.example.test.springvaadin.vaadin;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;

import com.example.test.springvaadin.entity.Role;
import com.example.test.springvaadin.service.RoleManager;

@Controller
public class Test { 
    private static final Logger logger = LoggerFactory.getLogger(Test.class);

    @Autowired
    private RoleManager roleManager;

    @RequestMapping("/test")
    public void doTest() {
        Role role = roleManager.findById(1);
        logger.info("_ROLE_TEST_ " + role.toString());
        String text = role.getName();       
    }
}

如果我去http：//ip.ip.ip.ip：8080 / springvaadin / test，我在日志中看到了（好的）： 

14:27:09.126 [tomcat-http--4] INFO  c.e.test.springvaadin.vaadin.Test - _ROLE_TEST_ Role [id=1, name=Test]

有二等艙： 

package com.example.test.springvaadin.vaadin;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.vaadin.spring.VaadinUI;

import com.example.test.springvaadin.entity.Role;
import com.example.test.springvaadin.service.RoleManager;
import com.vaadin.server.VaadinRequest;
import com.vaadin.ui.Label;
import com.vaadin.ui.UI;
import com.vaadin.ui.VerticalLayout;

@Controller // @Component do not work too
@VaadinUI
public class MainUI extends UI {

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

    @Autowired
    private RoleManager roleManager;

    @Override
    protected void init(VaadinRequest request) {
        logger.info("MAINUI IN INIT");
        final VerticalLayout layout = new VerticalLayout();
        layout.setMargin(true);
        setContent(layout);

        Role role = roleManager.findById(1);
        logger.info("_ROLE_VAADIN_ " + role.toString());
        String text = role.getName();

        Label lblRoleName = new Label(text);
        layout.addComponent(lblRoleName);       
    }
}

它由web.xml映射到/ ui 。 在頁面http：//ip.ip.ip.ip：8080 / springvaadin / ui上，我得到HTTP 500： 

14:29:50.810 [tomcat-http--14] INFO  c.e.test.springvaadin.vaadin.MainUI - MAINUI IN INIT
Čer 29, 2014 2:29:50 ODP. com.vaadin.server.DefaultErrorHandler doDefault
SEVERE: 
java.lang.NullPointerException
    at com.example.test.springvaadin.vaadin.MainUI.init(MainUI.java:40)
    at com.vaadin.ui.UI.doInit(UI.java:641)
    at com.vaadin.server.communication.UIInitHandler.getBrowserDetailsUI(UIInitHandler.java:222)
    at com.vaadin.server.communication.UIInitHandler.synchronizedHandleRequest(UIInitHandler.java:74)
    at com.vaadin.server.SynchronizedRequestHandler.handleRequest(SynchronizedRequestHandler.java:41)
    at com.vaadin.server.VaadinService.handleRequest(VaadinService.java:1405)
    at com.vaadin.server.VaadinServlet.service(VaadinServlet.java:237)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:108)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:409)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1044)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:607)
    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:313)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)

Čer 29, 2014 2:29:50 ODP. org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet [MainUI] in context with path [/springvaadin] threw exception [com.vaadin.server.ServiceException: java.lang.NullPointerException] with root cause
java.lang.NullPointerException
    at com.example.test.springvaadin.vaadin.MainUI.init(MainUI.java:40)
    at com.vaadin.ui.UI.doInit(UI.java:641)
    at com.vaadin.server.communication.UIInitHandler.getBrowserDetailsUI(UIInitHandler.java:222)
    at com.vaadin.server.communication.UIInitHandler.synchronizedHandleRequest(UIInitHandler.java:74)
    at com.vaadin.server.SynchronizedRequestHandler.handleRequest(SynchronizedRequestHandler.java:41)
    at com.vaadin.server.VaadinService.handleRequest(VaadinService.java:1405)
    at com.vaadin.server.VaadinServlet.service(VaadinServlet.java:237)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:108)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:409)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1044)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:607)
    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:313)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)

com.example.test.springvaadin.vaadin.MainUI.init（MainUI.java:40）處的java.lang.NullPointerException

但是它是文件中last }之后的類的最后一行。

Spring知道clase位於何處： 

<context:component-scan base-package="com.example.test.springvaadin.controller" />
<context:component-scan base-package="com.example.test.springvaadin.dao" />
<context:component-scan base-package="com.example.test.springvaadin.service" />
<context:component-scan base-package="com.example.test.springvaadin.vaadin" />

我做什么不好？ 使用過注解？

源代碼： https : //dl.dropboxusercontent.com/u/6943408/vaadin-spring_.zip

更新1：

我從MainUI類中刪除了@Controller注釋，現在它在第31行崩潰-“角色role = roleManager.findById（1）;” 有錯誤： 

Čer 29, 2014 8:50:22 ODP. com.vaadin.server.DefaultErrorHandler doDefault
SEVERE: 
java.lang.NullPointerException
    at com.example.test.springvaadin.vaadin.MainUI.init(MainUI.java:31)
    at com.vaadin.ui.UI.doInit(UI.java:641)
    at com.vaadin.server.communication.UIInitHandler.getBrowserDetailsUI(UIInitHandler.java:222)
    at com.vaadin.server.communication.UIInitHandler.synchronizedHandleRequest(UIInitHandler.java:74)
    at com.vaadin.server.SynchronizedRequestHandler.handleRequest(SynchronizedRequestHandler.java:41)
    at com.vaadin.server.VaadinService.handleRequest(VaadinService.java:1405)
    at com.vaadin.server.VaadinServlet.service(VaadinServlet.java:237)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:108)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:409)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1044)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:607)
    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:313)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)

Čer 29, 2014 8:50:22 ODP. org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet [MainUI] in context with path [/springvaadin] threw exception [com.vaadin.server.ServiceException: java.lang.NullPointerException] with root cause
java.lang.NullPointerException
    at com.example.test.springvaadin.vaadin.MainUI.init(MainUI.java:31)
    at com.vaadin.ui.UI.doInit(UI.java:641)
    at com.vaadin.server.communication.UIInitHandler.getBrowserDetailsUI(UIInitHandler.java:222)
    at com.vaadin.server.communication.UIInitHandler.synchronizedHandleRequest(UIInitHandler.java:74)
    at com.vaadin.server.SynchronizedRequestHandler.handleRequest(SynchronizedRequestHandler.java:41)
    at com.vaadin.server.VaadinService.handleRequest(VaadinService.java:1405)
    at com.vaadin.server.VaadinServlet.service(VaadinServlet.java:237)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:108)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:409)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1044)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:607)
    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:313)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)

1 個解決方案

解決方案1
 0  2014-07-02 13:36:05

如果搜索存儲庫 ，則可以看到有2個或3個選項。 我個人使用spring-vaadin-integration插件並根據其文檔 ，而不是像使用常規vaadin servlet那樣提供UI類： 

<servlet>
    <servlet-name>MainUI</servlet-name>
    <servlet-class>com.vaadin.server.VaadinServlet</servlet-class>      
    <init-param>
        <param-name>UI</param-name>
        <param-value>com.example.test.springvaadin.vaadin.MainUI</param-value>
    </init-param>
</servlet>

您需要提供春豆名稱 

<servlet>
    <servlet-name>MainUI</servlet-name>
    <servlet-class>ru.xpoft.vaadin.SpringVaadinServlet</servlet-class>
    <init-param>
        <param-name>beanName</param-name>
        <param-value>mainUI</param-value>
    </init-param>
</servlet>

當然，您的UI應該使用@Component注釋，並且可能使用@Scope("prototype")進行注釋： 

@Component
@Scope("prototype")
public class MainUI extends UI {    

    @Autowired
    private RoleManager roleManager;

    @Override
    protected void init(VaadinRequest request) {
        final VerticalLayout layout = new VerticalLayout();
        layout.setMargin(true);
        setContent(layout);

        Role r = new Role();
        r.setId(1);
        r.setName("Test");
        roleManager.save(r);

        String text = roleManager.findById(1).getName();

        Label lblRoleName = new Label(text);
        layout.addComponent(lblRoleName);       
    }
}

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