Spring 源码学习(3) —— 增加属性注册编辑器

创建一个实体类UserManager:

 /**
  * @filename: UserManager.java
  * @desc 增加属性编辑器功能测试实体类
  * @author: Wang Chinda
  * @blog http://www.cnblogs.com/goodcheap
  * @date: 2018-05-25 9:32
  * @version: v1.0
  * @copyright: Copyright © 2018 ༄ྂ祸ྂྂ害ོ༘苍ྂྂ生ོ༘࿐ྂ 版权所有
  * @modify_history: -
  * 20180525   Wang Chinda   create
  * 20180525   Wang Chinda   modify   method()
  */
 package com.itdoc.learn.source.add.attribute;

 import java.util.Date;

 /**
  * @desc 增加属性编辑器功能测试实体类
  * @author Wang Chinda
  * @create 2018-05-25 9:32
  */
 public class UserManager {

     private Date dateValue;

     public Date getDateValue() {
         return dateValue;
     }

     public void setDateValue(Date dateValue) {
         this.dateValue = dateValue;
     }

     @Override
     public String toString() {
         return "UserManager{" +
                 "dateValue=" + dateValue +
                 '}';
     }
 }

 创建配置文件:

 <?xml version="1.0" encoding="UTF-8"?>
 <beans xmlns="http://www.springframework.org/schema/beans"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">

     <bean id="getUserManager" class="com.itdoc.learn.source.add.attribute.UserManager">
         <property name="dateValue" value="2018-05-25"/>
     </bean>
 </beans>

测试:

 /**
  * @filename: AtrributeClient.java
  * @desc 增加属性编辑器测试客户端
  * @author: Wang Chinda
  * @blog http://www.cnblogs.com/goodcheap
  * @date: 2018-05-25 9:34
  * @version: v1.0
  * @copyright: Copyright © 2018 ༄ྂ祸ྂྂ害ོ༘苍ྂྂ生ོ༘࿐ྂ 版权所有
  * @modify_history: -
  * 20180525   Wang Chinda   create
  * 20180525   Wang Chinda   modify   method()
  */
 package com.itdoc.learn.source.add.attribute;

 import org.springframework.context.ApplicationContext;
 import org.springframework.context.support.ClassPathXmlApplicationContext;

 /**
  * @desc 增加属性编辑器测试客户端
  * @author Wang Chinda
  * @create 2018-05-25 9:34
  */
 public class AtrributeClient {

     public static void main(String[] args) {
         ApplicationContext app = new ClassPathXmlApplicationContext("test/add-attribute-editor-test.xml");
         UserManager userManager = (UserManager) app.getBean("getUserManager");
         System.out.println(userManager);
     }

 }

控制台显示:

五月 25, 2018 9:38:19 上午 org.springframework.context.support.AbstractApplicationContext prepareRefresh
信息: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@2ef9b8bc: startup date [Fri May 25 09:38:19 CST 2018]; root of context hierarchy
五月 25, 2018 9:38:19 上午 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
信息: Loading XML bean definitions from class path resource [test/add-attribute-editor-test.xml]
五月 25, 2018 9:38:19 上午 org.springframework.beans.factory.support.DefaultListableBeanFactory preInstantiateSingletons
信息: Pre-instantiating singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@3c22fc4c: defining beans [getUserManager]; root of factory hierarchy
五月 25, 2018 9:38:19 上午 org.springframework.beans.factory.support.DefaultSingletonBeanRegistry destroySingletons
信息: Destroying singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@3c22fc4c: defining beans [getUserManager]; root of factory hierarchy
Exception in thread "main" org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'getUserManager' defined in class path resource [test/add-attribute-editor-test.xml]: Initialization of bean failed; nested exception is org.springframework.beans.ConversionNotSupportedException: Failed to convert property value of type 'java.lang.String' to required type 'java.util.Date' for property 'dateValue'; nested exception is java.lang.IllegalStateException: Cannot convert value of type [java.lang.String] to required type [java.util.Date] for property 'dateValue': no matching editors or conversion strategy found
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:529)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:458)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:295)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:223)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:292)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:626)
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:932)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:479)
    at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:139)
    at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:83)
    at com.itdoc.learn.source.add.attribute.AtrributeClient.main(AtrributeClient.java:26)
Caused by: org.springframework.beans.ConversionNotSupportedException: Failed to convert property value of type 'java.lang.String' to required type 'java.util.Date' for property 'dateValue'; nested exception is java.lang.IllegalStateException: Cannot convert value of type [java.lang.String] to required type [java.util.Date] for property 'dateValue': no matching editors or conversion strategy found
    at org.springframework.beans.BeanWrapperImpl.convertIfNecessary(BeanWrapperImpl.java:463)
    at org.springframework.beans.BeanWrapperImpl.convertForProperty(BeanWrapperImpl.java:494)
    at org.springframework.beans.BeanWrapperImpl.convertForProperty(BeanWrapperImpl.java:488)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.convertForProperty(AbstractAutowireCapableBeanFactory.java:1433)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1392)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1128)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:519)
    ... 11 more
Caused by: java.lang.IllegalStateException: Cannot convert value of type [java.lang.String] to required type [java.util.Date] for property 'dateValue': no matching editors or conversion strategy found
    at org.springframework.beans.TypeConverterDelegate.convertIfNecessary(TypeConverterDelegate.java:264)
    at org.springframework.beans.BeanWrapperImpl.convertIfNecessary(BeanWrapperImpl.java:448)
    ... 17 more

出错原因: UserManager中的dateValue属性是Date类型, 而XML中配置的却是String类型。

Spring针对此问题提供了两种解决方案:

1. 使用自定义属性编辑器

使用自定义属性编辑器, 通过继承PropertyEditorSupport, 重写setAsText方法。

1). 编写自定义的属性编辑器:

 /**
  * @filename: DatePropertyEditor.java
  * @desc 自定义Date属性编辑器
  * @author: Wang Chinda
  * @blog http://www.cnblogs.com/goodcheap
  * @date: 2018-05-25 9:53
  * @version: v1.0
  * @copyright: Copyright © 2018 ༄ྂ祸ྂྂ害ོ༘苍ྂྂ生ོ༘࿐ྂ 版权所有
  * @modify_history: -
  * 20180525   Wang Chinda   create
  * 20180525   Wang Chinda   modify   method()
  */
 package com.itdoc.learn.source.add.attribute;

 import java.beans.PropertyEditorSupport;
 import java.text.ParseException;
 import java.text.SimpleDateFormat;
 import java.util.Date;

 /**
  * @desc 自定义Date属性编辑器
  * @author Wang Chinda
  * @create 2018-05-25 9:53
  */
 public class DatePropertyEditor extends PropertyEditorSupport {

     private String format = "yy-MM-dd";

     public void setFormat(String format) {
         this.format = format;
     }

     @Override
     public void setAsText(String text) throws IllegalArgumentException {
         System.out.println("text: " + text);
         SimpleDateFormat dateFormat = new SimpleDateFormat(format);
         try {
             Date date = dateFormat.parse(text);
             this.setValue(date);
         } catch (ParseException e) {
             e.printStackTrace();
         }
         super.setAsText(text);
     }
 }

2). 将自定义的属性编辑注册到Spring中:

 <?xml version="1.0" encoding="UTF-8"?>
 <beans xmlns="http://www.springframework.org/schema/beans"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">

     <bean id="getUserManager" class="com.itdoc.learn.source.add.attribute.UserManager">
         <property name="dateValue" value="2018-05-25"/>
     </bean>

     <bean class="org.springframework.beans.factory.config.CustomEditorConfigurer">
         <property name="customEditors">
             <map>
                 <entry key="java.util.Date">
                     <bean class="com.itdoc.learn.source.add.attribute.DatePropertyEditor"/>
                 </entry>
             </map>
         </property>
     </bean>
 </beans>

 控制台输出:

五月 25, 2018 10:11:34 上午 org.springframework.context.support.AbstractApplicationContext prepareRefresh
信息: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@2ef9b8bc: startup date [Fri May 25 10:11:34 CST 2018]; root of context hierarchy
五月 25, 2018 10:11:34 上午 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
信息: Loading XML bean definitions from class path resource [test/add-attribute-editor-test.xml]
五月 25, 2018 10:11:34 上午 org.springframework.beans.factory.config.CustomEditorConfigurer postProcessBeanFactory
警告: Passing PropertyEditor instances into CustomEditorConfigurer is deprecated: use PropertyEditorRegistrars or PropertyEditor class names instead. Offending key [java.util.Date; offending editor instance: com.itdoc.learn.source.add.attribute.DatePropertyEditor@6302bbb1
五月 25, 2018 10:11:34 上午 org.springframework.beans.factory.support.DefaultListableBeanFactory preInstantiateSingletons
信息: Pre-instantiating singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@6af93788: defining beans [getUserManager,org.springframework.beans.factory.config.CustomEditorConfigurer#0]; root of factory hierarchy
text: 2018-05-25
UserManager{dateValue=Fri May 25 00:00:00 CST 2018}

 2. 注册Spring自带的属性编辑器CustomDateEditor

 1).定义属性编辑器:

 /**
  * @filename: CustomDatePropertyEditor.java
  * @desc 实现Spring提供的自定义时间编辑器
  * @author: Wang Chinda
  * @blog http://www.cnblogs.com/goodcheap
  * @date: 2018-05-25 10:18
  * @version: v1.0
  * @copyright: Copyright © 2018 ༄ྂ祸ྂྂ害ོ༘苍ྂྂ生ོ༘࿐ྂ 版权所有
  * @modify_history: -
  * 20180525   Wang Chinda   create
  * 20180525   Wang Chinda   modify   method()
  */
 package com.itdoc.learn.source.add.attribute;

 import org.springframework.beans.PropertyEditorRegistrar;
 import org.springframework.beans.PropertyEditorRegistry;
 import org.springframework.beans.propertyeditors.CustomDateEditor;

 import java.text.SimpleDateFormat;
 import java.util.Date;

 /**
  * @desc 实现Spring提供的属性编辑器注册器, 应用CustomDateEditor
  * @author Wang Chinda
  * @create 2018-05-25 10:18
  */
 public class CustomDatePropertyEditor implements PropertyEditorRegistrar {

     @Override
     public void registerCustomEditors(PropertyEditorRegistry registry) {
         registry.registerCustomEditor(Date.class, new CustomDateEditor(new SimpleDateFormat("yy-MM-dd"), true));
     }
 }

2).注册到Spring中

 <?xml version="1.0" encoding="UTF-8"?>
 <beans xmlns="http://www.springframework.org/schema/beans"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">

     <bean id="getUserManager" class="com.itdoc.learn.source.add.attribute.UserManager">
         <property name="dateValue" value="2018-05-25"/>
     </bean>

     <bean class="org.springframework.beans.factory.config.CustomEditorConfigurer">
         <property name="propertyEditorRegistrars">
             <list>
                 <bean class="com.itdoc.learn.source.add.attribute.CustomDatePropertyEditor"/>
             </list>
         </property>
     </bean>
 </beans>

此处我换了另一个配置文件。

测试:

 /**
  * @filename: AtrributeClient.java
  * @desc 增加属性编辑器测试客户端
  * @author: Wang Chinda
  * @blog http://www.cnblogs.com/goodcheap
  * @date: 2018-05-25 9:34
  * @version: v1.0
  * @copyright: Copyright © 2018 ༄ྂ祸ྂྂ害ོ༘苍ྂྂ生ོ༘࿐ྂ 版权所有
  * @modify_history: -
  * 20180525   Wang Chinda   create
  * 20180525   Wang Chinda   modify   method()
  */
 package com.itdoc.learn.source.add.attribute;

 import org.springframework.context.ApplicationContext;
 import org.springframework.context.support.ClassPathXmlApplicationContext;

 /**
  * @desc 增加属性编辑器测试客户端
  * @author Wang Chinda
  * @create 2018-05-25 9:34
  */
 public class AtrributeClient {

     public static void main(String[] args) {
         ApplicationContext app = new ClassPathXmlApplicationContext("test/customEditor.xml");
         UserManager userManager = (UserManager) app.getBean("getUserManager");
         System.out.println(userManager);
     }

 }

GitHub源码: https://github.com/wcd19901010/spring-01