Spring学习之@Required注释

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@Required 注释应用于 bean 属性的 setter 方法，它表明受影响的 bean 属性在配置时必须放在 XML 配置文件中，否则容器就会抛出一个 BeanInitializationException 异常

Student.java：

import org.springframework.beans.factory.annotation.Required;

public class Student {
    private Integer age;
    private String name;
    
    @Required
    public void setAge(Integer age){
        this.age = age;
    }
    public Integer getAge(){
        return this.age;
    }
    
    @Required
    public void setName(String name){
        this.name = name;
    }
    public String getName(){
        return this.name;
    }
}

App.java：

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
public class MainApp {
   public static void main(String[] args) {
      ApplicationContext context = new ClassPathXmlApplicationContext("Beans.xml");
      Student student = (Student) context.getBean("student");
      System.out.println("Name : " + student.getName() );
      System.out.println("Age : " + student.getAge() );
   }
}

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"
    xmlns:context="http://www.springframework.org/schema/context"
    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">

   <context:annotation-config/>

   <bean id="student" class="com.tutorialspoint.Student">
      <property name="name"  value="Mike" />
      <property name="age"  value="11"/>
   </bean>

</beans>