Question

我在Spring MVC中使用Book Spring in Action开始，我正在使用Spitter应用程序练习第5章，但是我收到了以下错误：

org.springframework.beans.factory.UnsatisfiedDependencyException：在文件[C：\ xampp \ htdocs.metadata.plugins \ org.eclipse.wst.server.core \ ttmp1 \ wtpwebapps \中定义名称'spittleController'创建bean时出错spitter \ WEB-INF \ classes \ com \ spitter \ web \ SpittleController.class]：通过构造函数参数表达的不满意的依赖关系，类型为[com.spitter.data.SpittleRepository]的索引0 ::没有类型的限定bean [com.spitter]找到依赖项的.data.SpittleRepository]：预计至少有1个bean可以作为此依赖项的autowire候选者。依赖注释：{};嵌套异常是org.springframework.beans.factory.NoSuchBeanDefinitionException：没有为依赖项找到类型为[com.spitter.data.SpittleRepository]的限定bean：期望至少有一个bean可以作为此依赖项的autowire候选者。依赖注释：{}

我在github上获得了这个项目：https://github.com/kevingcfcb88/spitter.git

我已经完成了我的研究，但似乎没有任何效果。

我正在使用STS和Maven，这是应用程序的结构：

Project Structure

这是我的pom.xml

<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>com.spitter.config</groupId>
<artifactId>spitter</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>war</packaging>

<name>spitter</name>
<url>http://maven.apache.org</url>

<properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <springframework.version>4.1.5.RELEASE</springframework.version>
</properties>

<dependencies>
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>3.8.1</version>
        <scope>test</scope>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-webmvc</artifactId>
        <version>${springframework.version}</version>
    </dependency>
    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>javax.servlet-api</artifactId>
        <version>3.1.0</version>
    </dependency>
    <dependency>
        <groupId>javax.servlet.jsp</groupId>
        <artifactId>javax.servlet.jsp-api</artifactId>          
        <version>2.3.1</version>
    </dependency>
    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>jstl</artifactId>
        <version>1.2</version>
    </dependency>
    <!-- https://mvnrepository.com/artifact/org.apache.commons/commons-lang3 -->
    <dependency>
        <groupId>org.apache.commons</groupId>
        <artifactId>commons-lang3</artifactId>
        <version>3.0</version>
    </dependency>

</dependencies>

<build>
    <pluginManagement>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.2</version>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-war-plugin</artifactId>
                <version>2.4</version>
                <configuration>
                    <warSourceDirectory>src/main/webapp</warSourceDirectory>
                    <warName>spitter</warName>
                    <failOnMissingWebXml>false</failOnMissingWebXml>
                </configuration>
            </plugin>
        </plugins>
    </pluginManagement>
    <finalName>spitter</finalName>
</build>

我的配置文件：

SpittrWebAppInitializer.java

 package com.spitter.config;

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

public class SpittrWebAppInitializer 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[] { "/" };
    }

}

WebConfig.java

package com.spitter.config;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.ViewResolver;
import org.springframework.web.servlet.config.annotation.DefaultServletHandlerConfigurer;
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("com.spitter.web")
public class WebConfig extends WebMvcConfigurerAdapter {

    @Bean
    public ViewResolver viewResolver() {
        InternalResourceViewResolver resolver = new InternalResourceViewResolver();
        resolver.setPrefix("/WEB-INF/views/");
        resolver.setSuffix(".jsp");
        resolver.setExposeContextBeansAsAttributes(true);
        return resolver;
    }

    @Override
    public void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {
        configurer.enable();
    }

}

RootConfig.java

package com.spitter.config;

import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.ComponentScan.Filter;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.FilterType;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;

@Configuration
@ComponentScan(basePackages = { "com.spitter.data" }, excludeFilters = {@Filter(type = FilterType.ANNOTATION, value = EnableWebMvc.class) })
public class RootConfig {

}

Answer 1

正如@ mh-dev解释的那样，您需要实现SpittleRepository。尝试添加此类，看看您的代码是否可以运行：

public class SpittleRepositoryImpl implements SpittleRepository {

  List <Spittle> findSpittles(long max, int count) {
    System.out.println("I need a real implementation! " 
      + "I received max as " + max + " and count as " + count + ".");
  }

}

我建议您重新阅读本书的相关部分，以确保您不会遗漏任何内容。

Answer 2

你只需要在标题中添加一个带有@Repository的SpittleRepository的存储库实现，因为即使你已经添加了实现类，spring IOC也不知道实际的依赖性，如果你把所有的都放在了本书中的例子应该有效与存储库实现相同的包层次结构中的java文件。

@Repository
public class SpittleRepositoryDAO implements SpittleRepository {

    public SpittleRepositoryDAO() {

    }

    @Override
    public List<Spittle> findSpittles(long max, int count) {
        List<Spittle> spittles = new ArrayList<Spittle>();
        for (int i = 0; i < count; i++) {
            spittles.add(new Spittle("Spittle " + i, new Date()));
        }
        return spittles;
    }
}

Answer 3

我知道这段代码。 2年前它曾经给我带来严重的头痛。错误在代码或书籍中。

转到发布商网站并下载更新后的源代码。 here

或

https://www.manning.com/books/spring-in-action-fourth-edition

Answer 4

以下是存储库的实现：

package com.spitter.web;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;

import com.spitter.data.SpittleRepository;

@Controller
@RequestMapping("/spittles")
public class SpittleController {

    private SpittleRepository spittleRepository;

    @Autowired
    public SpittleController(SpittleRepository spittleRepository) {
        this.spittleRepository = spittleRepository;
    }

    @RequestMapping(method = RequestMethod.GET)
    public String spittles(Model model) {
        model.addAttribute("spittleList", spittleRepository.findSpittles(Long.MAX_VALUE, 20));
        return "spittles";
    }

}

Answer 5

是的，问题是您需要实现 SpittleRepository 。因为你知道，因为你不能把接口作为bean。扫描组件至少需要一个实现，并且需要注释@Component。就是这样;）

Spitter不满意的依赖异常Spring MVC

5 个答案: