我是 Spring 的新手。我正在尝试在我们的项目中使用 Autowiring 。但是我在服务类中遇到了问题。 我的服务等级:
package com.x.y.service;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import com.x.y.dao.RegionDao;
import com.x.y.util.model.Region;
@Service("regionService")
public class RegionServiceImpl implements RegionService{
@Autowired
RegionDao regionDao;
public List<Region> getAllCities() {
return regionDao.getAllCities();
}
}
我的道课:
package com.x.y.dao;
import java.util.ArrayList;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.support.rowset.SqlRowSet;
import org.springframework.stereotype.Repository;
import com.x.y.util.model.Region;
@Repository("regionDao")
public class RegionDaoImpl{
@Autowired
private JdbcTemplate jdbcTemplate;
public List<Region> getAllCities(){
StringBuffer strbuf = new StringBuffer();
try{
strbuf.append(" SELECT REGION_ID,REGION_NAME,REGION_TYPE_ID,ST_AsText(THE_GEOM) AS geom FROM REGION WHERE REGION_TYPE_ID = 1");
SqlRowSet rowset = jdbcTemplate.queryForRowSet(strbuf.toString());
Region region = null;
List<Region>regions = new ArrayList<Region>();
while(rowset.next()){
region = new Region();
region.setRegionId(rowset.getLong("REGION_ID"));
region.setRegionName(rowset.getString("REGION_NAME"));
region.setRegionTypeId(rowset.getInt("REGION_TYPE_ID"));
regions.add(region);
}
return regions;
}catch(Exception e){
return null;
}
}
}
web.xml:
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:jsp="http://java.sun.com/xml/ns/javaee/jsp" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5">
<display-name>xy.in</display-name>
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>
/WEB-INF/test-*.xml
</param-value>
</context-param>
<filter>
<filter-name>encoding-filter</filter-name>
<filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
<init-param>
<param-name>encoding</param-name>
<param-value>UTF-8</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>encoding-filter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<filter>
<filter-name>GzipFilter</filter-name>
<filter-class>com.cj.gzipflt.GzipFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>GzipFilter</filter-name>
<url-pattern>*.jsp</url-pattern>
</filter-mapping>
<filter-mapping>
<filter-name>GzipFilter</filter-name>
<url-pattern>*.htm</url-pattern>
</filter-mapping>
<filter-mapping>
<filter-name>GzipFilter</filter-name>
<url-pattern>*.css</url-pattern>
</filter-mapping>
<filter-mapping>
<filter-name>GzipFilter</filter-name>
<url-pattern>*.jpg</url-pattern>
</filter-mapping>
<filter-mapping>
<filter-name>GzipFilter</filter-name>
<url-pattern>*.gif</url-pattern>
</filter-mapping>
<filter-mapping>
<filter-name>GzipFilter</filter-name>
<url-pattern>*.js</url-pattern>
</filter-mapping>
<filter-mapping>
<filter-name>GzipFilter</filter-name>
<url-pattern>*.png</url-pattern>
</filter-mapping>
<servlet>
<servlet-name>test</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>test</servlet-name>
<url-pattern>*.htm</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>test</servlet-name>
<url-pattern>*.json</url-pattern>
</servlet-mapping>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<listener>
<listener-class>
org.springframework.web.context.request.RequestContextListener</listener-class>
</listener>
<jsp-config>
<taglib>
<taglib-uri>http://java.sun.com/jstl/core</taglib-uri>
<taglib-location>/WEB-INF/tld/c.tld</taglib-location>
</taglib>
<taglib>
<taglib-uri>http://java.sun.com/jstl/fmt</taglib-uri>
<taglib-location>/WEB-INF/tld/fmt.tld</taglib-location>
</taglib>
</jsp-config>
<error-page>
<error-code>404</error-code>
<location>/WEB-INF/jsp/pageNotFound.jsp</location>
</error-page>
<error-page>
<error-code>500</error-code>
<location>/WEB-INF/jsp/pageNotFound.jsp</location>
</error-page>
<session-config>
<session-timeout>30</session-timeout>
</session-config>
</web-app>
测试servlet.xml:
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:p="http://www.springframework.org/schema/p"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:util="http://www.springframework.org/schema/util"
xmlns:task="http://www.springframework.org/schema/task"
xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd
http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-3.0.xsd
http://www.springframework.org/schema/task
http://www.springframework.org/schema/task/spring-task-3.0.xsd">
<context:component-scan base-package="com.x.y.web.controller" />
<bean id="localeChangeInterceptor"
class="org.springframework.web.servlet.i18n.LocaleChangeInterceptor"
p:paramName="locale" />
<!-- Declare the Resolver -->
<bean id="localeResolver"
class="org.springframework.web.servlet.i18n.SessionLocaleResolver" />
<bean id="messageSource"
class="org.springframework.context.support.ReloadableResourceBundleMessageSource">
<property name="basename" value="/WEB-INF/messages/bizmaps" />
<property name="cacheSeconds" value="1" />
<property name="useCodeAsDefaultMessage" value="true" />
</bean>
<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
</bean>
<bean id="xmlFileViewResolver" class="org.springframework.web.servlet.view.XmlViewResolver">
<property name="location">
<value>/WEB-INF/views.xml</value>
</property>
<property name="order">
<value>1</value>
</property>
</bean>
<bean id="viewResolver"
class="org.springframework.web.servlet.view.ContentNegotiatingViewResolver">
<property name="mediaTypes">
<map>
<entry key="htm" value="text/html" />
<entry key="json" value="application/json" />
</map>
</property>
<property name="viewResolvers">
<list>
<bean id="internalView"
class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="viewClass"
value="org.springframework.web.servlet.view.JstlView" />
<property name="prefix" value="/WEB-INF/jsp/" />
<property name="suffix" value=".jsp" />
<property name="order">
<value>1</value>
</property>
</bean>
</list>
</property>
<property name="defaultViews">
<list>
<bean
class="org.springframework.web.servlet.view.json.MappingJacksonJsonView">
<property name="prefixJson" value="true" />
</bean>
</list>
</property>
</bean>
<!-- JSON configuration for arabic support -->
<bean name="jsonView" class="org.springframework.web.servlet.view.json.JsonView">
<property name="encoding">
<value>UTF-8</value>
</property>
<property name="contentType">
<value>application/json</value>
</property>
<property name="jsonWriter">
<ref bean="sojoJsonWriter" />
</property>
<property name="jsonErrors">
<list>
<ref bean="statusError" />
<ref bean="modelflagError" />
</list>
</property>
</bean>
<bean id="jsonView2" class="org.springframework.web.servlet.view.json.MappingJacksonJsonView"/>
<bean name="sojoJsonWriter"
class="org.springframework.web.servlet.view.json.writer.sojo.SojoJsonStringWriter">
<property name="convertAllMapValues">
<value>false</value>
</property>
</bean>
<bean name="statusError"
class="org.springframework.web.servlet.view.json.error.HttpStatusError">
<property name="errorCode">
<value>311</value>
</property>
</bean>
<bean name="modelflagError"
class="org.springframework.web.servlet.view.json.error.ModelFlagError">
<property name="name">
<value>failure</value>
</property>
<property name="value">
<value>true</value>
</property>
</bean>
<!-- JSON configuration end -->
<bean
class="org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping">
<property name="interceptors">
<list>
<ref bean="localeChangeInterceptor" />
</list>
</property>
<property name="order" value="1" />
</bean>
<bean id="urlMapping"
class="org.springframework.web.servlet.handler.SimpleUrlHandlerMapping">
<property name="mappings">
<props>
<prop key="/**/*.htm">viewController</prop>
</props>
</property>
</bean>
<bean id="viewController"
class="org.springframework.web.servlet.mvc.UrlFilenameViewController" />
</beans>
测试服务.xml:
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:p="http://www.springframework.org/schema/p"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:util="http://www.springframework.org/schema/util"
xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd
http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-3.0.xsd"
default-autowire="byName">
<context:component-scan base-package="com.x.y.service">
<context:include-filter type="annotation"
expression="org.springframework.stereotype.Service"/>
</context:component-scan>
<import resource="test-dao.xml"/>
</beans>
测试-dao.xml:
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:p="http://www.springframework.org/schema/p" xmlns:context="http://www.springframework.org/schema/context"
xmlns:util="http://www.springframework.org/schema/util" xsi:schemaLocation=" http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd http://www.springframework.org/schema/util
http://www.springframework.org/schema/util/spring-util-3.0.xsd" default-autowire="byName">
<context:component-scan base-package="com.x.y.dao">
<context:include-filter type="annotation" expression="org.springframework.stereotype.Repository"/>
</context:component-scan>
<bean id="propertyConfigurer"
class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
<property name="location">
<value>classpath:/database.properties</value>
</property>
</bean>
<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource"
destroy-method="close">
<property name="driverClassName">
<value>${postgres.connection.driver_class}</value>
</property>
<property name="url">
<value>${postgres.connection.url}</value>
</property>
<property name="username">
<value>${postgres.connection.username}</value>
</property>
<property name="password">
<value>${postgres.connection.password}</value>
</property>
<property name="maxActive">
<value>-1</value>
</property>
<property name="maxIdle">
<value>-1</value>
</property>
<property name="initialSize">
<value>10</value>
</property>
</bean>
<bean id="jdbcTemplate"
class="org.springframework.jdbc.core.JdbcTemplate">
<property name="dataSource" ref="dataSource"/>
</bean>
</beans>
我遇到的错误:
SEVERE: Exception sending context initialized event to listener instance of class org.springframework.web.context.ContextLoaderListener
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'regionService': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: com.x.y.dao.RegionDao com.x.y.service.RegionServiceImpl.regionDao; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No matching bean of type [com.x.y.dao.RegionDao] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:285)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1074)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:517)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:456)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:291)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:288)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:190)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:580)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:895)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:425)
at org.springframework.web.context.ContextLoader.createWebApplicationContext(ContextLoader.java:276)
at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:197)
at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:47)
at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4135)
at org.apache.catalina.core.StandardContext.start(StandardContext.java:4630)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:791)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:771)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:568)
at org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:637)
at org.apache.catalina.startup.HostConfig.deployDescriptors(HostConfig.java:563)
at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:498)
at org.apache.catalina.startup.HostConfig.start(HostConfig.java:1282)
at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:321)
at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:142)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1053)
at org.apache.catalina.core.StandardHost.start(StandardHost.java:807)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1045)
at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:445)
at org.apache.catalina.core.StandardService.start(StandardService.java:519)
at org.apache.catalina.core.StandardServer.start(StandardServer.java:710)
at org.apache.catalina.startup.Catalina.start(Catalina.java:581)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:289)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:414)
Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: com.x.y.dao.RegionDao com.x.y.service.RegionServiceImpl.regionDao; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No matching bean of type [com.x.y.dao.RegionDao] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:502)
at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:84)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:282)
... 37 more
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No matching bean of type [com.x.y.dao.RegionDao] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoSuchBeanDefinitionException(DefaultListableBeanFactory.java:920)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:789)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:703)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:474)
... 39 more
请帮助我。我们将不胜感激。
最佳答案
RegionDaoImpl 应该实现 RegionDao。错误信息的关键位是
No matching bean of type [com.x.y.dao.RegionDao] found
关于java - 服务类中的 Spring Autowired 异常，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/8623821/