java - bean 类 [Person] 的无效属性 'messageService ' - Spring Framework

Question

我在尝试使用 Spring 框架进行依赖注入(inject)时遇到此错误

Invalid property 'messageService ' of bean class [Person]: Bean property 'messageService ' is not writable or has an invalid setter method. Did you mean 'messageService'?

这是我的类(class)人员:

public class Person {
    private MessageService messageService;

    public void setMessageService(MessageService messageService){
          this.messageService  = messageService;
    }

    public MessageService getMessageService() {
          return this.messageService;
    }

    public void Chao(String Subject, String Message)
    {
        messageService.sendMessage(Subject,Message);
    }

}

这是我的 Beans.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" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">
   <bean id="email" class="Email"></bean>
   <bean id="Person" class="Person">
       <property name="messageService " ref="email"></property>
   </bean>
</beans>

最后是主类

public class Main {

    public static void main(String args[]) throws Exception{
        ApplicationContext context = new ClassPathXmlApplicationContext("Beans.xml"); 

        Person test = (Person) context.getBean("Person");
        test.Chao("abc","abc");
    }
}

MessageService是一个接口(interface)，类Email实现了MessageService有人能告诉我我做错了什么吗？非常感谢

Answer 1

name="messageService " 末尾有一个空格。请删除它。