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Spring框架:用实用程序:映射

spring java

emeraldjava · 技术社区 · 16 年前

public class GenericEntityFactoryImpl implements GenericEntityFactory
{
    private Map<IndexType,IEntity> indexEntityMap = null;

    @Override
    public IEntity getIndexEntity(IndexType index) {
        return indexEntityMap.get(index);
    }

    public Map<IndexType, IEntity> getIndexEntityMap() {
        return indexEntityMap;
    }

    public void setIndexEntityMap(Map<IndexType, IEntity> indexEntityMap) {
        this.indexEntityMap = indexEntityMap;
    }
}

我的弹簧有问题实用程序:地图布线,因为我不确定在定义键值时如何正确引用特定的枚举类型。映射值的bean引用很简单。所有SpringMap连接的示例似乎都假设键是一个字符串!

<!-- the value object bean -->
<bean id="cell" class="com.xx.xx.common.index.entity.CellEntity"/>

<bean id="genericEntityFactory" class="com.xx.xx.common.index.GenericEntityFactoryImpl">
  <util:map 
       id="indexEntityMap" 
       map-class="java.util.HashMap" 
       key-type="com.xx.xx.common.index.IndexType" 
       value-type="com.xx.xx.common.index.GenericEntityFactoryImpl">
           <entry key="CELL">
                <ref bean="cell"/>
            </entry>
       </util:map>
</bean>

所以我重构了映射

<bean id="genericEntityFactory" class="com.xx.xx.common.index.GenericEntityFactoryImpl" >
    <property name="indexEntityMap">
        <map >
            <entry key="com.xx.xx.common.index.CELL"><ref bean="cell"/></entry>
        </map>   
    </property>
</bean>

但是,假设春天是聪明的失败了。。。

Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'genericEntityFactory' defined in class path resource [com/xx/xx/common/index/index-application-context.xml]: Initialization of bean failed; nested exception is org.springframework.beans.TypeMismatchException: Failed to convert property value of type [java.util.LinkedHashMap] to required type [java.util.Map] for property 'indexEntityMap'; nested exception is java.lang.IllegalArgumentException: Cannot convert value of type [java.lang.String] to required type [com.xx.xx.common.index.IndexType] for property 'indexEntityMap[com.xx.xx.common.index.CELL]': no matching editors or conversion strategy found
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:480)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory$1.run(AbstractAutowireCapableBeanFactory.java:409)
    at java.security.AccessController.doPrivileged(Native Method)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:380)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:264)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:221)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:261)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:185)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:164)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:429)
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:729)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:381)
    at org.springframework.test.context.support.AbstractGenericContextLoader.loadContext(AbstractGenericContextLoader.java:84)
    at org.springframework.test.context.support.AbstractGenericContextLoader.loadContext(AbstractGenericContextLoader.java:42)
    at org.springframework.test.context.TestContext.loadApplicationContext(TestContext.java:173)
    at org.springframework.test.context.TestContext.getApplicationContext(TestContext.java:197)
    ... 17 more
Caused by: org.springframework.beans.TypeMismatchException: Failed to convert property value of type [java.util.LinkedHashMap] to required type [java.util.Map] for property 'indexEntityMap'; nested exception is java.lang.IllegalArgumentException: Cannot convert value of type [java.lang.String] to required type [com.xx.xx.common.index.IndexType] for property 'indexEntityMap[com.xx.xx.common.index.CELL]': no matching editors or conversion strategy found
    at org.springframework.beans.BeanWrapperImpl.convertForProperty(BeanWrapperImpl.java:391)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.convertForProperty(AbstractAutowireCapableBeanFactory.java:1288)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1249)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1010)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:472)
    ... 32 more
Caused by: java.lang.IllegalArgumentException: Cannot convert value of type [java.lang.String] to required type [com.xx.xx.common.index.IndexType] for property 'indexEntityMap[com.xx.xx.common.index.CELL]': no matching editors or conversion strategy found
    at org.springframework.beans.TypeConverterDelegate.convertIfNecessary(TypeConverterDelegate.java:219)
    at org.springframework.beans.TypeConverterDelegate.convertToTypedMap(TypeConverterDelegate.java:508)
    at org.springframework.beans.TypeConverterDelegate.convertIfNecessary(TypeConverterDelegate.java:194)
    at org.springframework.beans.TypeConverterDelegate.convertIfNecessary(TypeConverterDelegate.java:138)
    at org.springframework.beans.BeanWrapperImpl.convertForProperty(BeanWrapperImpl.java:386)
    ... 36 more

4 回复 | 直到 13 年前

emeraldjava 10 年前

我找到了一个解决方法,将我计划添加到映射中的每个枚举定义为一个单独的bean—多亏了 creating-spring-bean-from-java-5-enum

<bean id="CELL" class="com.xx.xx.common.index.IndexType" factory-method="valueOf">
    <constructor-arg>
        <value>CELL</value>
    </constructor-arg>
</bean>

<bean id="APN" class="com.xx.xx.common.index.IndexType" factory-method="valueOf">
    <constructor-arg>
        <value>APN</value>
    </constructor-arg>
</bean>

定义了枚举之后,我可以在地图中对它们进行键引用

<bean id="genericEntityFactory" class="com.xx.xx.common.index.GenericEntityFactoryImpl" >
    <property name="indexEntityMap">
        <map>
            <entry key-ref="CELL"><ref bean="cell"/></entry>
            <entry key-ref="APN"><ref bean="apn"/></entry>
        </map>   
    </property>
</bean>

Betlista 13 年前

以下是另一种较短的格式:

<bean id="versionService" class="my.service.VersionService" 
        p:animalDAOMap-ref="animalDAOMap"/>

<util:map id="p:animalDAOMap">
    <entry key="chicken" value-ref="chickenDAO"/>
    <entry key="monkey" value-ref="monkeyDAO"/>
    <entry key="pig" value-ref="pigDAO"/>
</util:map>

确保包含命名空间

xmlns:util="http://www.springframework.org/schema/util"

http://www.springframework.org/schema/util 
http://www.springframework.org/schema/util/spring-util-3.0.xsd

顺便说一下,我在这里使用的是Spring3.0+

Mosolov Sergey 9 年前

和你犯了同样的错误。我可以通过将枚举移到独立文件并公开枚举来避免它。

所以我的

public enum EventType { INFO, ERROR }

放置在

事件类型.java

而且我只有一个包裹,如果这有什么关系的话。我以这种方式(通过构造函数arg的xml)注入依赖关系:

<constructor-arg>
    <map>
        <entry key="INFO" value-ref="consoleEventLogger"></entry>
        <entry key="ERROR" value-ref="combinedEventLogger"></entry>
    </map>
</constructor-arg>

我用的是SpringCore4.3.6

我相信有一种解释,那取决于反思和内在的弹簧逻辑。但是我没有太多的Java经验,我不能提供这些。

-1

mR_fr0g 16 年前

<bean id="genericEntityFactory" class="com.xx.xx.common.index.GenericEntityFactoryImpl">
  <property name="indexEntityMap" ref="indexEntityMapBean"/>
</bean>

<util:map id="indexEntityMapBean" 
       map-class="java.util.HashMap" 
       key-type="com.xx.xx.common.index.IndexType" 
       value-type="com.xx.xx.common.index.GenericEntityFactoryImpl">
           <entry key="com.xx.xx.common.index.IndexType.CELL">
                <ref bean="cell"/>
           </entry>
</util:map>

你用 <util:map 而不是更干净的注释 <map> (见第节) 3.3.3.3 )如果您想将同一个映射连接到多个地方,或者您想使用不同的基础映射实现,例如ConcurrentHashMap。