java - 实例化 org.springframework.beans.propertyeditors.StringTrimmerEditor 的 bean 时出错

Question

这是我的 applicationContext.xml 的样子:

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:sec="http://www.springframework.org/schema/security"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:p="http://www.springframework.org/schema/p"
       xmlns:tx="http://www.springframework.org/schema/tx"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.0.xsd
        http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.0.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd
        http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd
        http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd
        http://www.springframework.org/schema/security http://www.springframework.org/schema/security/spring-security-3.2.xsd">

............

<bean id="customEditorConfigurer" class="org.springframework.beans.factory.config.CustomEditorConfigurer">
   <property name="customEditors">
        <map>
           <entry key="java.lang.String">
                <ref bean="stringTrimmerEditor"/>
            </entry>
        </map>
    </property>
 </bean>

我收到此错误:

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'customEditorConfigurer' defined in ServletContext resource [/WEB-INF/spring-servlet.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 'customEditors'; nested exception is java.lang.IllegalArgumentException: Cannot convert value of type [org.springframework.beans.propertyeditors.StringTrimmerEditor] to required type [java.lang.Class] for property 'customEditors[java.lang.String]': PropertyEditor [org.springframework.beans.propertyeditors.ClassEditor] returned inappropriate value of type [org.springframework.beans.propertyeditors.StringTrimmerEditor]

Answer 1

documentation for the setCustomEditors method of the CustomEditorConfigurer class声明如下(强调我的):

Specify the custom editors to register via a Map, using the class name of the required type as the key and the class name of the associated PropertyEditor as value

因此，您传入类名，而不是 bean 本身，作为映射中每个条目的值。

尝试更换

<entry key="java.lang.String">
    <ref bean="stringTrimmerEditor"/>
</entry>

<罢工>与

<entry key="java.lang.String"
       value="org.springframework.beans.propertyeditors.StringTrimmerEditor" />

<罢工>

与

<entry key="java.lang.String">
    <bean class="org.springframework.beans.propertyeditors.StringTrimmerEditor">
        <!-- change the value as necessary.  --> 
        <constructor-arg name="emptyAsNull" value="false" />  
    </bean>
</entry>